SF's largest cook pine - leaning towards the equator!

September 27, 2025 by Michael Sullivan

I recently discovered a huge cook pine (Araucaria columnaris) in the Golden Gate Park panhandle - I think it’s the largest in San Francisco. Thanks to professor Matt Ritter at Cal Poly, we’ve learned that these trees always lean towards the equator. The tree is on the south side of the panhandle, just off the path that is parallel with Fell Street, and between Clayton and Cole streets. This one is duly leaning south!

Glen Park 2.0 Tour (Poppy Lane; Penny Lane; Ohlone Way) (7-13-25)

July 14, 2025 by Michael Sullivan

On a typical foggy, windy day in San Francisco, we returned to the charming Glen Park neighborhood to explore more of its trees—and its three unpaved alleys (two “lanes” and one “way”). As the fog cleared, captivating views opened to this hilly district and out of it to the south. Yet, the diversity of trees, the sometimes quirky architecture, and the delightful, albeit small, gardens along the way are what bring us back to Glen Park.

This tree walk begins on Sussex Street at the corner of Elk Street, and heads east along Sussex for three blocks to Conrad Street, where it heads north (uphill) for a short block to Poppy Lane. It turns into Poppy Lane and continues along this mostly unpaved “alley” to Diamond Street, where it turns right and heads downhill past Sussex to Penny Lane, another mostly unpaved alley. It heads southeast on Penny Lane to its end, where it becomes a set of neighborhood-created steps among California native plantings, ending at Surrey Street. It then heads northwest on Surrey, crossing Diamond again, and continuing along Surrey to Ohlone Way, the third unpaved alley on this walk. It heads up Ohlone to Sussex, then left on Sussex to Van Buren Street, and back downhill on Van Buren to Surrey. From there, it heads west on Surrey to its merge with Chenery Street, and on west on Chenery to the end of the walk at Elk. This walk is 1 ½ miles long.

Numbered trees are labeled with common and scientific names and country of origin, all written in white chalk on the sidewalk; accompanying numbers, in blue, run from 1 to 41. White arrows on the pavement provide directions whenever a turn is needed.

The street addresses provided below will help when the chalk has faded. Most of the trees are planted in pockets in the sidewalk pavement; a few are planted on private property between the sidewalk and the homes, and in rear gardens.

Sussex Street, Elk to Mizpah, south side

1. 395 Sussex Monterey pine (Pinus radiata), CA native: Año Nuevo, Monterey, Cambria, plus Cedros and Guadalupe islands, MX (most widely planted coniferous tree in the world, mostly for lumber)

2.395 Sussex Brazilian pepper tree (Schinus terebinthifolia), Brazil, Argentina, Paraguay

3. 385 Sussex Carob (Ceratonia siliqua), E Mediterranean Basin (there are several trees in this block; seed pods can be used to make a chocolate substitute—though not recommended for true chocolate lovers)

Sussex Street, Mizpah to Swiss Street, south side

4. 1 Mizpah English hawthorn (Crataegus laevigata), W & C Europe

5. 333 Sussex Cook pine (Araucaria columnaris), New Caledonia (similar to Norfolk Island pine, but this narrower, denser species always has a curve at the base of the trunk and a pronounced lean, usually toward the equator)

6. 333. Sussex Guadalupe palm (Brahea edulis), Guadalupe Island, Mexico (this palm is perfectly adapted to SF; it has been used in the median of Cesar Chavez Street in the Mission District)

7. 301 Sussex Purple Robe hybrid locust (Robinia ‘Purple Robe’), hybrid of N American species (fragrant pink flowers in early summer)

8. 301 Sussex Two holly trees (Ilex species), Eurasia & N Africa (probably derived from the English holly, Ilex aquifolium)

Swiss Street at Sussex, west side

9. 116 Swiss Strawberry tree (Arbutus unedo) SW Europe to Ireland (a fine specimen; fruits are edible, though bland)

Sussex Street, Swiss to Conrad, south side

10a. 291 Sussex Primrose tree (Lagunaria patersonia), Norfolk and Lord Howe islands (soft pink flowers usually appear in summer)

10b. 291 Sussex Myoporum or ngaio in Māori (Myoporum laetum), New Zealand (this species is dying all over San Francisco, due to an insect pest called thrips that disfigures the new shoots; note that the leaves are poisonous)

11. 261 Sussex Flowering cherry (Prunus serrulata), Japan (watch for the pink flowers in April; note the point at which it was grafted unto an understock, about two feet above ground level)

12. 201 Sussex Marina strawberry tree (Arbutus ‘Marina’), hybrid of 3 Mediterranean species (first introduced in San Francisco)

13. 201 Sussex Hybrid tea tree (Leptospermum ‘Dark Shadows’), Australia

14. [not used]

**Cross Sussex carefully**

Sussex Street, west of Conrad, north side

15. 194 Sussex Hollywood juniper (Juniperus chinensis ‘Torulosa’ or ‘Kaizuka’), E Asia

Conrad Street, north of Sussex, west side

16. 120 Conrad Chinese elm (Ulmus parvifolia), China, Korea, Japan, and Vietnam (a particularly fine large specimen)

**Cross Conrad safely**

Conrad Street, north of Sussex, east side

17. 123 Conrad Sweetgum (Liquidambar styraciflua), E USA to Mexico & Central America (3 trees on Conrad and 1 at the corner of the residential property)

**Enter Poppy Lane; the lack of pavement prohibits labeling trees. The California Buckeye is about 200’ in, on the left, in the large rear garden of a house on Arbor Street.

California buckeye (*Aesculus californica*) [photo from June]

18. Poppy Lane California buckeye (Aesculus californica), California & Oregon; a San Francisco native tree! (this is the largest in the city; it’s just finished flowering, with fruits developing on many of the inflorescences)

**Along Poppy Lane, you’ll see a coast redwood, Canary Island date Palm, and avocado trees on the left, and purple hopseed bush, a struggling walnut, and a loquat in full fruit on the right

Diamond Street, Poppy Lane to Sussex, west side

19. 2590 Diamond Red-flowering gum (Corymbia ficifolia), SW Australia (produces bright red, orange, or pink flowers in summer; among the best and showiest of trees in SF’s urban forest; we cannot understand why the city is no longer planting this amazing tree)

Diamond Street, at SW corner of Sussex

20. 2600 Diamond Meyer lemon (Citrus x meyeri), hybrid of mandarin and pomelo, both SE Asian species

**Cross the heavily traveled Diamond Street safely

Diamond Street, Sussex to Penny Lane, east side

21. 2607 Diamond Giant yucca (Yucca gigantea, formerly Y. elephantipes), Mexico & Central America

22. 2607 Diamond Blue spruce (Picea pungens), Rocky Mountains (a particularly blue form)

23. 2609 Diamond African fern pine (Afrocarpus falcatus, formerly A. gracilior), E & S Africa

**Enter Penny Lane; the huge coast live oak is marked by a chalk label on bricks on the right side of the lane

24. Penny Lane Coast live oak (Quercus agrifolia), SF and CA native; Baja to Mendocino, always within 50 miles of the coast (this may be the largest specimen in the city—a truly glorious tree)

**Along Penny Lane, you’ll see fruit trees (mostly plums) on both sides, plus Italian buckthorn on the right, and a badly pruned incense cedar on the left. At the end of the lane, the stepped pathway leads down to Surrey Street through a planting of California natives, including fremontia and Matilija poppy.

** Cross Surrey Street carefully

Surrey Street, north of Penny Lane, west side

25. 53 Surrey Golden showers tree (Koelreuteria bipinnata), S China

26. 55 Surrey Water gum (Tristaniopsis laurina), E Australia (the northern tree of the pair, with smaller leaves; this tree grows in stream-side locations in the wild, hence the common name; SF’s most commonly planted street tree)

Elegant water gum (Tristaniopsis laurina ‘Elegant’), E Australia (the southern of the two trees; this selection of the water gum has longer, glossier leaves than the species)

27. 73 Surrey New Zealand Christmas tree, pōhutukawa in Māori (Metrosideros excelsa), New Zealand (many trees on throughout the neighborhood; this tree flowers most reliably in the summer months, which would be Christmas time in NZ, south of the equator; this specimen has been heavily pruned to allow sunlight through and thus is not flowering this year)

28. 99 Surrey Weeping bottlebrush (Callistemon viminalis), E Australia

**Cross Diamond Street carefully

Surrey Street, Diamond to Lippard, south side

29. 2700 Diamond Southern magnolia (Magnolia grandiflora), SE USA (3 trees along Diamond; many in the neighborhood)

30a. 2700 Diamond Red ironbark (Eucalyptus sideroxylon), E & SE Australia (3 trees along Surrey with dark, deeply fissured bark; red to pink flowers in spring)

Surrey Street, Lippard to Ohlone Way, south side

30b. 1 Lippard Queen palm (Syagrus romanzoffiana), S Brazil (2 trees on Surrey)

**Cross Surrey Street carefully, and turn right into Ohlone Way, the third unpaved alley on this walk; with little pavement, no labels have been chalked. As you walk up Ohlone Way, note the beautiful mural acknowledging the prior inhabitants of this land, the Ohlone people. You’ll see a small California buckeye and large specimens of Douglas-fir, Monterey cypress, and Monterey pine on the left; on the right, you’ll see plum and a bizarre English ivy “tree” growing atop the stump of an old cypress.

Sussex Street, Ohlone Way to Van Buren Street, south side

31. 135 Surrey Mayten (Maytenus boaria), Chile (2 young trees along Sussex, with gracefully pendant branches, resembling those of weeping willows)

Van Buren Street, Sussex to Surrey, east side

32. 3 Van Buren Lemon bottlebrush (Callistemon citrinus), E Australia (several trees on this block of Van Buren, all pruned into lollipop shapes)

33. 55 Van Buren Washington thorn (Crataegus phaenopyrum) E USA (note the last of the white flowers that will become colorful fruits in late fall; this specimen lacks the characteristic long thorns along its branches)

34. 75 Van Buren Swamp paperbark (Melaleuca ericifolia), SE Australia

**Cross Van Buren Street carefully

Van Buren Street at Sussex, NW corner

35. 70 Van Buren Douglas-fir (Pseudotsuga menziesii), West Coast & Rocky Mountains (tall conifer with needle-like leaves in the side yard; a CA native tree!)

Surrey Street, Van Buren to Swiss, north side

36. 320 Surrey Ruby Glow New Zealand tea tree (Leptospermum scoparium ‘Ruby Glow’), New Zealand (a small tree with tiny dark green leaves and small red flowers in winter and spring)

37. 326 Surrey Pygmy date palm (Phoenix roebelenii), S China, Laos, Vietnam (a good use of this small palm)

38. 151 Swiss California buckeye (Aesculus californica ), California & Oregon; a San Francisco native tree! (this younger specimen on Surrey Street is still flowering)

Surrey Street, Swiss to Chenery, north side

39. 100 Swiss Wollemi pine (Wollemia nobilis), E Australia (this rare tree, inside the fenced corner of the garden, has only grown a foot since we noted it on our Glen Park walk in late 2020; google it to read the intriguing story of the tree’s discovery in the mid-1990s)

40. 398 Surrey Canary Island pine (Pinus canariensis), Canary Islands (surprisingly uncommon in SF, these pines have noticeably long needles)

Chenery Street, Surrey to Elk, north side

41. 1006 Chenery Ginkgo (Ginkgo biloba), China (these distinctive deciduous trees are the last of an ancient lineage of Gymnosperms)

This walk ends at Elk, across the street from the Glen Park Recreation Center, and one block downhill from its start at Sussex Street.

Our regular commercial: This walking tour was organized by Mike Sullivan, author of The Trees of San Francisco and webmaster of www.sftrees.com; Jason Dewees, horticulturist at Flora Grubb Gardens and author of Designing with Palms; Richard Turner, retired editor of Pacific Horticulture magazine and Sairus Patel, soon to be author of Trees of Stanford. You can follow Mike and Jason on their tree-themed Instagram pages at @sftreeguy and @loulufan. Richard edited another great book on San Francisco trees: Elizabeth McClintock’s Trees of Golden Gate Park. If you’re a tree enthusiast, buy all four of these books!

Noe Valley Uber-North Tree Tour (6-28-25)

July 02, 2025 by Michael Sullivan

Noe Valley Uber North Tree Tour

On a bright and cheerful morning of Pride weekend, we returned to tree-rich Noe Valley, specifically to the northern reaches just before the crest of a hill that separates Noe and Eureka valleys. The south and west facing slopes of this neighborhood offer opportunities for the diversity of trees for which Noe Valley is known. Along the way, we saw delightful, environmentally practical front gardens, views across the valley to the Pink Diamond on Twin Peaks, and an array of architectural styles, including several homes by the late, talented architect, Philip Mathews. We begin at Alvarado Elementary School, one of San Francisco’s most highly regarded.

Today’s walk begins at the main entrance to Alvarado Elementary School, 625 Douglass Street. It heads north on Douglass to 22nd Street, then east along 22nd to Diamond Street. It continues north on Diamond to 21st Street, where it turns east for a short climb up and down to Collingwood Street. There, it crosses 21st and returns west on the north side of 21st to Eureka Street. From there, it heads south on Eureka to 22nd, and west on 22nd to its end at Douglass, a few steps north of its beginning. The walk is under a mile in length.

Numbered trees are labeled with common and scientific names and country of origin, all written in white chalk on the sidewalk; accompanying numbers, in blue, run from 1 to 30. White arrows on the pavement provide directions whenever a turn is needed.

Douglass Street, 23rd to 22nd streets, east side

1. 625 Douglass New Zealand Christmas tree, pōhutukawa in Māori (Metrosideros excelsa), New Zealand (many trees on throughout the neighborhood; this tree flowers most reliably in the summer months, which would be Christmas time in NZ, south of the equator)

2. 618 Douglass European weeping birch (Betula pendula), Eurasia & N Africa (not usually well-adapted to SF, but this specimen is doing well behind the white picket fence across the street)

22nd Street, Douglass to Eureka streets, south side

3. N side of school Evergreen pear (Pyrus kawakamii), Taiwan (row of 4 trees; only in particularly cold winters does this species lose its leaves in San Francisco)

4. 4112 - 22nd Bronze loquat (Rhaphiolepis deflexa, syn. Eriobotrya deflexa), S China and Vietnam (across the street; distinctive for its bronzy new foliage; fruits are inedible)

22nd Street at Eureka Street, south side

5. 4055 - 22nd Victorian box (Pittosporum undulatum), E Australia (2 trees here, but common in the neighborhood; intensely fragrant white flowers cycle through the year, followed by sticky fruits, seen here on the sidewalk)

22nd Street, Eureka to Diamond streets, north side

6. 499 Eureka Silver maple (Acer saccharinum), E North America (tree is on 22nd Street; uncommon in San Francisco)

7. 4018 - 22nd Red-flowering gum (Corymbia ficifolia), SW Australia (produces bright red, orange, or pink flowers in summer; among the best and showiest of trees in SF’s urban forest; we cannot understand why the city is no longer planting this amazing tree)

8. 4000 - 22nd Red maple (Acer rubrum), Eastern North America

Diamond Street, 22nd to 21st streets, east side

9. 493 Diamond Purple-leaf plum (Prunus cerasifera), Eurasia (pink flowers usually appear by February; formerly SF’s most planted street tree; usually without leaves through fall and winter)

10. 493 Diamond Canary Island date palm (Phoenix canariensis), Canary Islands, Spain (a single large tree partway up the hill alongside this address; this is the species seen in the median of Upper Market Street and along the Embarcadero)

**Note the fine specimen of New Zealand Christmas tree at 481 Diamond, with the distinctive aerial roots dropping down from upper branches; in the wild, these roots would reach the soil and develop as secondary trunks to support the heavy branches on old trees)

11. 455 Diamond California buckeye (Aesculus californica ), California & Oregon; a San Francisco native tree! (it’s just finished flowering, with fruits developing on some of the inflorescences)

12. 433 Diamond Cajeput tree (Melaleuca quinquenervia), New Caledonia, New Guinea, NE Australia (3 trees; feel the spongy bark)

13. Diamond Coast live oak (Quercus agrifolia), SF and CA native; Baja to Mendocino, always within 50 miles of the coast

21st Street, Diamond to Collingwood streets, south side

14. 401 Diamond Hopseed tree (Dodonaea viscosa), native throughout tropical and subtropical parts of the world (two trees are on 21st Street; most commonly seen in its purple-leafed form)

**As you approach Collingwood Street, note the fantastic view of the city skyline and the Bay.

21st Street, Collingwood to Diamond streets, north side

15. 4014 - 21st New Zealand tea tree (Leptospermum scoparium), New Zealand

**Note the beautifully executed water-conserving garden in front of these residences

16. 4042 - 21st Elegant water gum (Tristaniopsis laurina ‘Elegant’), E Australia (3 trees; this selection of the water gum has longer, glossier leaves than the species)

Diamond Street at 21st Street, west side

17. 396 Diamond Pineapple guava (Feijoa sellowiana, also know as Acca sellowiana), Brazil (though this does not reliably set fruit in cool San Francisco, the white and pink flowers are attractive, and the white petals are edible)

18. 404 Diamond African fern pine (Afrocarpus falcatus, formerly A. gracilior), E & S Africa (3 young trees)

21st Street, Diamond to Eureka streets, south side

19. 4103 - 21st Chinese pistache (Pistacia chinensis), W & C China (not commonly planted in SF, since it prefers greater summer heat to develop its spectacular fall foliage colors)

20. 4107 - 21st Champak (Magnolia champaca) S & SE Asia (small, magnolia-like flowers, appearing in summer, are intensely fragrant; this species has been showing quite yellow green leaves in the city this year)

21. 4145 - 21st Marina strawberry tree (Arbutus ‘Marina’), hybrid of Mediterranean species (first introduced in San Francisco)

22. 4145 - 21st Peruvian pepper tree (Schinus molle), Peru, Brazil, & Chile

Eureka Street, north of 21st Street, west side

23. 388 Eureka Ginkgo (Ginkgo biloba), China (across the street; these distinctive deciduous trees are the last of an ancient lineage of Gymnosperms)

24. 398 Eureka Queen palm (Syagrus romanzoffiana), S Brazil (5 trees on 21st Street); note the Pride pink triangle in the background

Eureka Street, 21st to 22nd streets, east side

25. 449 Eureka Snow-in-summer tree or flax-leaf paperbark (Melaleuca linariifolia), E Australia (feel the spongy bark; white flowers cover the tree in summer)

26. 432 Eureka Washington thorn (Crataegus phaenopyrum) E USA (across the street; note the white flowers that will become colorful fruits in late fall; this specimen lacks the characteristic long thorns along its branches)

27. 444 Eureka Japanese zelkova (Zelkova serrata), China, Korea, and Japan (across the street)

28. 471 Eureka Hollywood juniper (Juniperus chinensis ‘Torulosa’ or ‘Kaizuka’), E Asia (not a tree usually recommended for use as a street tree due to its dense low-branching habit)

21st Street, Eureka to Douglass streets, north side

29. 490 Eureka Indian laurel fig (Ficus microcarpa ‘Nitida’), S Asia to N Australia (tree is on 22nd Street; formerly one of SF’s most planted trees)

30. 4120 - 22nd Jacaranda (Jacaranda mimosifolia), Argentina, Bolivia (now deciduous, this tree will burst into bloom in early July; these heat loving trees are becoming more common in SF, especially in warmer areas of the city—all thanks to climate change)

Today’s walk ends at the corner of 22nd and Douglass streets, a few steps from its beginning in front of the school.

Street Tree Species Selection - "Take it or Leave it"?

March 13, 2025 by Michael Sullivan

The Chronicle came out with a story today about a couple in the Richmond District who battled for almost 4 years to plant two trees in front of their home (replacing one tree that had blown over in a storm, and one that had dangerous structural problem). The story follows a pattern that we’ve seen in other areas of City government: residents try to do something with their home, business or property, and run into bureaucratic hassles. There’s a lot to digest in the article, but I’d like to focus on one aspect of the story.

This couple wanted to plant a “little gem magnolia”. Little gems are a dwarf cultivar of the Southern Magnolia (Magnolia grandiflora) that are generally considered appropriate for most locations, because of their relatively small size. However, according to the article, “DPW told the couple that the magnolia wouldn’t work because of its extensive root system”. Instead of giving the couple a list of permitted trees, DPW then suggested just one: Ceanothus (presumably Ceanothus ‘Ray Hartman”, which is the only cultivar of the species that can be grown into a small tree). When the couple rejected that idea and pushed for the magnolia, the City first consented (but required the couple to sign a legal agreement to assume liability for the tree), and then changed its mind, denying the planting permit entirely.

DPW ultimately relented, and allowed the couple to plant a sweet michelia (Magnolia doltsopa) as a compromise, but only after the Chronicle got involved.

Putting bureaucratic hassles aside, what strikes me about this story is how forceful the City is becoming with species selection. Ever since the City assumed responsibility for tree maintenance when the “StreetTreeSF” ballot initiative passed in 2008, DPW has gotten stricter in disallowing certain tree species, especially those that become very large or present above-average risk of failure. In general, that all makes sense (although as regular readers of sftrees.com know, I really think that an exception should be made for red flowering gums).

But this case takes things to an entirely new level. It’s one thing to limit tree selection to a list of trees that generally don’t present problems. It’s another to mandate the species that a homeowner can plant. If the article is accurate, this is a situation where a small tree was suggested, and the response was to reject the proposal and tell the homeowners to plant just one species.

I hope that this is a one-off situation, and that things haven’t gotten to the point where anyone who wants to plant a tree will be told what to plant - given one “take it or leave it” idea. Letting people plant what they want (and giving them a range of choices) has a number of benefits. First, people are more likely to look out for their tree if they got a tree that they love - more likely to water it in the summer heat (and I’ve seen some DPW trees that have died in summer heat waves) and more likely to help if the tree is knocked over by a truck or a winter storm. And second, it makes people happy, and connects them to their home and their neighborhoods.

Let’s be more flexible for residents who want to green our streets!

Prunus campanulata (Taiwan cherry or Formosan cherry)

Taiwan Cherry - Rare and Beautiful! (2-24-25)

March 03, 2025 by Michael Sullivan

Richard Turner tipped me off to this beautiful tree at 171 Hartford (just downhill from 19th Street) in the Castro neighborhood. It’s Prunus campanulata (common name Taiwan cherry or Formosan cherry). More common in Southern California, but very rare here in San Francisco (I don’t know of another one in the City). Photo credits to Richard!

Castro - Divisadero Tree Tour (2-15-25)

February 18, 2025 by Michael Sullivan

A busy thoroughfare, a quiet residential street, a dead-end road, and a schoolyard filled with native plants—all this in today’s tree walk. We have dubbed this neighborhood Castro-Divisadero, as it incorporates the triangle at the merging of Castro and Divisadero streets. It falls just beyond the Castro, Duboce Triangle, Corona Heights Park, Buena Vista Park, and Haight neighborhoods. Some surprisingly mature trees can be found along the way.

Today’s walk begins at the main entrance to the McKinley Elementary School, 1025 14th Street. It heads east on 14th to Castro Street, then south along Castro to Henry Street. It continues west for half a block on Henry before returning to and crossing Castro, then north on the east side of Castro to Duboce Avenue. At Duboce, it crosses Castro and continues north on the west side of Castro to it’s merger with Divisadero Street. From there, it heads south on Divisadero to the end of Divisadero at 14th. The walk is a bit over a mile in length.

Numbered trees are labeled with common and scientific names and country of origin, all written in white chalk on the sidewalk; accompanying numbers, in blue, run from 1 to 42. White arrows on the pavement provide directions whenever a turn is needed.

The street addresses provided below will help when the chalk has faded. Many of the first trees on this walk are planted around the outer edges of the McKinley Elementary School playground (noted as McKinley below); some are planted around the Davies Hospital campus (noted as Davies below); others are planted in sidewalk pockets; and a few are planted within the front or rear gardens of homes along the route.

14th Street, Divisadero to Castro, south side

1. 1025 - 14th Mayten (Maytenus boaria), Chile (many trees along 14th Street, with gracefully pendant branches, resembling those of weeping willows)

**Head down the steps or the ramp towards the school building**

2. 1025 - 14th Santa Cruz Island ironwood (Lyonothamnus floribundus ssp. aspleniifolius), CA’s Channel Islands, except Catalina Island

3. McKinley Owlswood Blue ceanothus (Ceanothus arboreus x thyrsiflorus ‘Owlswood Blue’), hybrid of California native species

Blackwood acacia (Acacia melanoxylon), SE Australia (young tree with unusually rounded phyllodes)

Meyer lemon (Citrus x meyeri), hybrid of mandarin and pomelo, both SE Asian species

4. McKinley Toyon (Heteromeles arbutifolia), CA and SF native! (birds have already eaten the brightly colored fruits for which this small tree is known; commonly seen in natural areas in SF, particularly the Presidio and Bay View Hill.

5. McKinley Coast redwood (Sequoia sempervirens), Big Sur to SW Oregon; CA coastal native (this species is the tallest tree in the world)

6. McKinley California buckeye (Aesculus californica), California & Oregon; a San Francisco native tree! (it’s just leafing out)

Castro Street, 14th to Henry, west side

7. McKinley Southern magnolia (Magnolia grandiflora), SE USA (this species was planted extensively along Castro Street, on both sides, from here to Market Street; the largest trees, south of Henry Street, were planted in the early 70s)

8. McKinley African fern pine (Afrocarpus falcatus, formerly A. gracilior), E & S Africa

9. McKinley Sydney golden wattle (Acacia longifolia), E Australia (this species was used extensively in the early plantings of Golden Gate Park)

Henry Street, west of Castro, north side

10. McKinley Torrey pine (Pinus torreyana), San Diego County, and Santa Rosa Island, CA (this long-needled pine, though adaptable in cultivation, is the rarest pine species in the world, found only on the coast near La Jolla and Del Mar, and on Santa Rosa Island off Santa Barbara; these are among the largest specimens in SF)

11. McKinley Canary Island pine (Pinus canariensis), Canary Islands (surprisingly uncommon in SF, these pines have even longer needles than the Torrey pines nearby)

12. McKinley London plane tree (Platanus x hispanica), hybrid of E USA species and Mediterranean species (this deciduous tree is among the most commonly planted trees in cities around the world outside the tropics)

Henry Street, west of Castro, south side

13. 265 Henry Peppermint willow (Agonis flexuosa), SW Australia

14. 150 Castro Incense cedar (Calocedrus decurrens), CA native; Oregon to Baja (tree is in the rear garden on Henry; the wood is used in construction and for making pencils)

15. 150 Castro Avocado tree (Persea americana), Mexico & Central America (tree is in the rear garden on Henry)

***Cross Castro carefully at the crosswalk; note the rows of Southern Magnolia stretching along Castro to the south***

Henry Street, east of Castro, south side

16. 197 Henry Ginkgo (Ginkgo biloba), China (these distinctive deciduous trees are the last of an ancient lineage of gymnosperms)

Henry Street, east of Castro, north side

17. 149 Castro Marina strawberry tree (Arbutus ‘Marina’), hybrid of Mediterranean species (row of 3 trees on Henry; first introduced in San Francisco)

Castro Street, 14th to Duboce, east side

18. Davies Monterey cypress (Hesperocyparis macrocarpa), Carmel, CA, native (one of the most widely planted conifers in coastal California; numerous mature trees border the Davies Hospital parking garage)

19. Davies Monterey pine (Pinus radiata), CA native: Año Nuevo, Monterey, Cambria, plus Cedros and Guadalupe islands, MX (several can be seen mixed with the Monterey pines around the parking garage; most widely planted coniferous tree in the world, mostly for lumber)

20. 60 Castro Sweetgum (Liquidambar styraciflua), E USA to Mexico & Central America (across the street; this tallest tree on the block is holding onto last year’s leaves, which will drop as this year’s leaves emerge)

21. 36 Castro Brisbane box (Lophostemon confertus), E Australia (this block of Castro is lined with this species, most planted at the time of the construction of Davies Hospital in the 1960s; some are among the largest in the city)

***Cross Castro at the traffic signal***

Castro Street at Duboce, west side

22. 2 Castro Blackwood acacia (Acacia melanoxylon), SE Australia (this young tree, situated far too close to the building, is likely a seedling of the mature specimen a few yards uphill on Duboce)

Castro Street, Duboce to Divisadero, west side

23. 754 Duboce Lombardy poplar (Populus nigra ‘Italica’), a narrow-growing cultivar of a Eurasian species (2 deciduous trees in the corner bed)

24. 754 Duboce Brush cherry (Syzygium australe, formerly S. paniculatum), E Australia

a sidewalk square from 1931! (across from the silk oak near where Castro and Divisadero meet)

25. 9-11 Castro Silk oak (Grevillea robusta), E Australia (across the street, in the walled yard to the south of the building; known for their bright yellow orange flowers in late spring in areas with a warmer climate, these two trees seldom flower due to the chill of the city)

Divisadero Street, Castro to Duboce, east side

26. 170 Divisadero Hollywood juniper (Juniperus chinensis ‘Torulosa’ or ‘Kaizuka’), E Asia

27. 170 Divisadero Olive (Olea europaea), Mediterranean Basin

28. 154 Divisadero Chinese windmill palm (Trachycarpus fortunei), China (3 trees)

29. 154 Divisadero Water gum (Tristaniopsis laurina), E Australia (this tree grows in stream-side locations in the wild, hence the common name; SF’s most commonly planted street tree)

30. 140 Divisadero Ponytail palm (Beaucarnea guatemalensis), Central America (a rare species in cultivation, particularly in SF)

31. 140 Divisadero Hybrid pōhutukawa in Māori (Metrosideros excelsa x kermadecensis), New Zealand mainland and Kermadec Islands (the rounded leaves, relatively few aerial roots, and winter flowers suggest that this tree is a hybrid)

32. 126 Divisadero Peruvian pepper tree (Schinus molle), Peru, Brazil, & Chile

33. 108 Divisadero Jacaranda (Jacaranda mimosifolia), Argentina, Bolivia (these heat loving trees are becoming more common in SF, especially in warmer areas of the city—all thanks to climate change)

Duboce Avenue, Divisadero to Castro, north side

34. 760 Duboce Willow-leaf peppermint (Eucalyptus nicholii), SE Australia (2 trees, mid-block on Duboce)

35. 106 Divisadero Japanese black pine (Pinus thunbergii), Japan and S Korea (tree is on Duboce at the corner)

Divisadero Street, Duboce to 14th, west side

36. 99 Divisadero Tree fuchsia (Fuchsia arborescens), C America (this large shrubby fuchsia flowers all year in SF)

37. 99 Divisadero Hercules tree aloe (Aloidendron ‘Hercules’), hybrid of two S African species (note the diverse plantings in this garden designed by the talented Dan Carlson)

38. 67 Divisadero Purple-leaf plum (Prunus cerasifera), Eurasia (pink flowers usually appear by February; formerly SF’s most planted street tree; usually without leaves through fall and winter)

39. 61 Divisadero Hybrid hibiscus (Hibiscus rosa-sinensis), tropical Asia (not known to thrive in SF’s cool climate, but this specimen is doing well in a protected corner of the building)

40. 55 Divisadero Thornless honey locust (Gleditsia triacanthos ‘Inermis’), E USA

41. 42 Divisadero Indian laurel fig (Ficus microcarpa ‘Nitida’), S Asia to N Australia (the entire block, from here to 14th, is planted on both sides with this tree; formerly one of SF’s most planted trees)

42. 16 Divisadero Bailey’s acacia (Acacia baileyana), E Australia (this is usually among the earliest flowering trees in SF, always beginning in January with fluffy bright yellow flowers, which are now done on this fine specimen)

The tour ends here, just a few yards from its start at McKinley Elementary School.

Oceanside Walking Tour (1-26-25)

January 28, 2025 by Michael Sullivan

On yet another mild, dry winter day (will it ever rain again this season?), we visited the neighborhood known as Oceanview, in the southwestern quadrant of San Francisco. This is a densely built neighborhood, with houses close to the street, leaving little room for street trees. Fortunately, the neighborhood benefits from the trees that surround the Millie & Lovie Ward Recreation Center, which fills the block bounded by Plymouth and Capitol avenues and Montana and Lobos streets. The mature Monterey cypresses on the west, south, and east sides of the Rec Center are among the healthiest in the city, undoubtedly due to the extra rain and fog typical in this section of the Alemany Gap.

A delightful surprise, to those of us not from the neighborhood, was the planted median on the long block of Minerva Street, just west of Plymouth; it’s filled with a variety of small trees and palms, flowering shrubs, succulents, and art.

It was encouraging to note that Friends of the Urban Forest (FUF) has been planting young street trees throughout the neighborhood, wherever sidewalk space permitted. This is part of a concerted effort on the part of both the city’s Urban Forestry Division and FUF to provide more shade in areas of the city that have typically lacked tree cover. With a warming climate, the importance of trees to provide shade and cool the environment cannot be stressed enough.

Today’s walk begins at the main entrance to the Millie & Lovie Ward Recreation Center at Capitol Avenue (cross is Minerva Street). It heads south on Capitol just past Lobos Street, then returns to Lobos and heads east to Plymouth Avenue, and north on Plymouth. At Minerva Street, the walk heads east up the gentle part of the hill to about midway, crosses the median at the red steps, and returns to Plymouth. It then continues north on Plymouth, west on Montana Street, and finally south on Capitol to the beginning of the walk at Minerva. This walk is about 1 mile in length.

Numbered trees are labeled with common and scientific names and country of origin, all written in white chalk on the sidewalk; accompanying numbers, in blue, run from 1 to 32. White arrows on the pavement provide directions whenever a turn is needed.

Capitol Avenue, Minerva to Lobos, east side

1. Rec Ctr Monterey cypress (Hesperocyparis macrocarpa), Carmel, CA, native (opposite 545 Capitol; one of the most widely planted conifers in coastal California; mature trees surround the Rec Ctr on the west, south, and east)

2. Rec Ctr Jester conebush (Leucadendron ‘Jester’), hybrid of S African species (corner of Capitol & Lobos and Plymouth & Lobos

Capitol Avenue, south of Lobos, east side

3. 438 Capitol Eureka lemon tree (Citrus x limon ‘Eureka’) hybrid of S Asia species (not commonly grown in SF)

4. 438 Capitol Southern magnolia (Magnolia grandiflora), SE USA

**Cross the street carefully**

Capitol Avenue, south of Lobos, west side

5. Corner school grounds Hybrid pōhutukawa in Māori (Metrosideros excelsa x kermadecensis), New Zealand mainland and Kermadec Islands (opposite 438 Capitol; the rounded leaves, relatively few aerial roots, and winter flowers suggest that this tree is a hybrid)

Lobos Street, Capitol to Plymouth, south side

6. 177 Lobos Brisbane box (Lophostemon confertus), E Australia

**Cross the street carefully**

Lobos Street, Capitol to Plymouth, north side

7. Rec Ctr Peppermint willow (Agonis flexuosa), SW Australia (opposite 171 Lobos)

8. Rec Ctr Santa Cruz Island ironwood (Lyonothamnus floribundus ssp. aspleniifolius), CA’s Channel Islands, except Catalina Island (opposite 171 Lobos; a number of these native trees have been planted on the slope above the sidewalk)

9. Rec Ctr Cajeput tree (Melaleuca quinquenervia), New Caledonia, New Guinea, NE Australia (opposite 159 Lobos)

10. Rec Ctr Holm oak (Quercus ilex), Mediterranean Basin (several trees opposite 151 Lobos; a surprisingly uncommon tree in SF, despite its adaptability to our climate;

11. Rec Ctr Water gum (Tristaniopsis laurina), E Australia (opposite 139 Lobos; this tree grows in stream-side locations in the wild, hence the common name; SF’s most commonly planted street tree)

12. Rec Ctr Bronze loquat (Eriobotrya deflexa, syn. Rhaphiolepis deflexa), S China and Vietnam (opposite 131 Lobos)

13. Rec Ctr Coast live oak (Quercus agrifolia), SF and CA native; Baja to Mendocino, always within 50 miles of the coast (2 trees opposite 119 Lobos; though native to SF, these specimens are not thriving as well as the nearby Holm oaks)

14. Rec Ctr Marina strawberry tree (Arbutus ‘Marina’), hybrid of Mediterranean species (corner Lobos & Plymouth; first introduced in San Francisco; larger ones are around the corner on Plymouth)

Plymouth Avenue, Lobos to Minerva, west side

15. Rec Ctr Olive (Olea europaea), Mediterranean Basin (opposite 512 Plymouth)

Minerva Street median, east of Plymouth, south side

16. Median Coast blueblossom (Ceanothus thyrsiflorus), coastal S Oregon to CentralCalifornia; a San Francisco native (opposite 554 Plymouth)

17. Median Red-tip photinia (Photinia x fraseri), hybrid (opposite 88 Minerva; more commonly seen as a dense shrub with red new foliage along CA freeways)

18. Median Mexican fan palm (Washingtonia robusta), S Baja & Sonora, Mexico (opposite 85 Minerva)

19. Median Pink melaleuca (Melaleuca nesophila), W Australia (opposite 71 Minerva)

20. Median Giant yucca (Yucca gigantea, formerly Y. elephantipes), Mexico & Central America (opposite 63 Minerva)

21. Median Torch aloe (Aloe arborescens), S & SE Africa (opposite 57 Minerva; though the scientific name suggests that this is “tree-like”, it rarely is more than a big shrub; notable for its reliable flowering during CA winters)

22. Median Mediterranean fan palm (Chamaerops humilis), W Mediterranean Basin: Portugal & Morocco to Tunisia & Italy (opposite 55 Minerva; this is a young specimen that will grow into a low multi-trunked tree; it has the northernmost natural range of any palm in the world)

**Cross to north side of Minerva, using the red concrete steps; watch the traffic**

Minerva Street median, east of Plymouth, north side

23. Median Red escallonia (Escallonia rubra), S Chile and Argentina, all the way to Tierra del Fuego (opposite 30 Minerva; normally grown as a dense large shrub, this one has been pruned into an attractive multi-trunk tree)

24. Median Cabbage tree or tī kōuka in Māori (Cordyline australis), New Zealand (opposite 36 Minerva)

25. Median Monterey cypress (Hesperocyparis macrocarpa), Carmel, CA, native (opposite 80 Minerva; this tree is only about 10 years old; compare with the mature trees around the Rec Ctr)

Plymouth Avenue, Minerva to Montana, east side

26. 668 Plymouth African fern pine (Afrocarpus falcatus, formerly A. gracilior), E & S Africa

Montana Street, Plymouth to Capitol, south side

27. Rec Ctr Pussy willow (Salix sp.), California (opposite 136 Montana; the flowers, resembling the paws of a kitten, will appear soon)

28. Rec Ctr Saratoga laurel (Laurus ‘Saratoga’), hybrid of Mediterranean and Atlantic species (opposite 148 Montana; several trees inside the fence; a selected form introduced by Saratoga Horticultural Foundation)

Montana Street, Plymouth to Capitol, north side

29. 158 Montana Angel’s trumpet (Brugmansia ‘Charles Grimaldi’), Andes (tree is across the street, with large pendant, trumpet-like flowers; named for the late, well-known garden designer in SF)

30. 194 Montana Island oak (Quercus tomentella), California’s Channel Islands (a CA native) and Guadalupe Island, Mexico (this young tree represents a new species introduction that should thrive in the city’s climate)

Capitol Avenue, Montana to Minerva, west side

31. 201 Capitol Japanese camellia (Camellia japonica), E Asia (though usually grown as a shrub for its beautiful late winter/spring flowers, Japanese camellia is actually a small tree)

32. 601 Capitol After Dark peppermint willow (Agonis flexuosa ‘Jervis Bay Afterdark’), SW Australian cultivar (2 trees in sidewalk pockets; often less vigorous than the green-leafed species; compare with a green-leafed specimen of this species at #7 on this walk)

This tour ends here, across the street from its start at the main entrance to the Rec Ctr.

Poppy Lane Buckeye

January 22, 2025 by Michael Sullivan

I was in Glen Park recently and decided to check out the massive California buckeye (Aesculus californica) on Poppy Lane - one of the quaint unpaved alleys in the Glen Park neighborhood. It’s looking great - I think it’s likely the largest California buckeye in the City. Check it out - Poppy Lane between Conrad and Diamond!

What a Find!

November 15, 2024 by Michael Sullivan

I love the hunt for great trees in San Francisco. Unlike many cities, where the local government determines what is planted, and entire avenues are planted with one species, San Francisco has always given residents the right to plant what they want (within reason), which over the years has contributed to a wonderful diversity of trees in the neighborhoods. You never know what you’ll find around the corner, a serendipity that contributes to my love of San Francisco streets. And the only thing better than finding an amazing tree is finding an amazing tree in a totally unexpected place.

That’s what happened in June of this year, when Richard Turner, Jason Dewees, Sairus Patel and I were chalking our 50th chalk tree on Nob HIll, a neighborhood famous for its many tiny alleys. As we were walking west on Sacramento Street, we came upon Golden Court, which is so small that it’s not even on many maps. It’s too small for cars - Golden Alley is actually a long sidewalk that leads to the addresses along the way.

We decided to check out the alley (single file!), and you can imagine our surprise to find an amazing specimen of a lacebark tree (Brachychiton discolor) near the end of the alley. This is a tree so rare in San Francisco that the four of us knew of only one other example in the entire city. This one was a large specimen in the bloom of health.

So the next time you’re at the Fairmont Hotel or Grace Cathedral, take a 3 or 4 minute stroll to Golden Court, to see San Francisco’s “city champion” lacebark tree!

Eureka Valley West Tree Tour (8-23-24)

August 27, 2024 by Michael Sullivan

Who would have expected that the tree geeks would be rained out on a Saturday in late August? Yet, that is exactly what happened when Mike, Sairus, and Dick chose to meet at the corner of 18th and Storrie streets, a few blocks west of Castro Street, to explore the trees in this western corner of Eureka Valley. The clouds had been threatening on Friday and into the early hours of Saturday. Almost exactly at the appointed meeting time, light rains began, and continued for over an hour—all the result of a former typhoon that bypassed Japan in favor of a modest hit to California.

With sidewalks too wet to accept chalk, the geeks decided to walk the route and photograph some of the outstanding trees to be seen on the streets and in private gardens along the way. This is a quiet neighborhood, on the far edge of the Castro District, with homes ranging from historic Victorian and Edwardian to trendy contemporary styles. Trees can be seen in abundance, as might be expected of this moderately upscale neighborhood with its well-educated population. Among the trees noted are some city champions, and some markedly uncommon trees for San Francisco.

Today’s walk begins at the unnamed community garden on the southern side of the one-block-long Storrie Street, from Market to 18th streets. Previously a leftover strip of undeveloped land with topographical challenges, it has in recent decades evolved into a delightful public park, almost all at the hands of a local, born-in-San Francisco chap who tends the garden daily. (He’s happy to chat with anyone who drops in to see the garden.) The park is notable for some giant cottonwoods (Populus sp.) and a few eucalypts and their kin from Australia.

We strolled west on 18th, passing the former Sha’ar Zahav Jewish synagogue before turning south onto 19th Street, which curves around and heads east after crossing Caselli Avenue. At Yukon Street, we noted the large Monterey pines (Pinus radiata) in Goat Hill Park on the far corner, before turning north on Yukon Street. We turned east (right) on Caselli and followed it to tiny Clover Lane, which rises to Thorp Lane. We followed Thorp east to its end at 19th, and headed east on 19th to Douglass Street. There we turned north, walking past the glorious Caselli Mansion at Douglas and Caselli. We ended our walk at 18th. Our walk was roughly a mile in length.

We may return to this neighborhood for a properly chalked walk, but, in the interim, we hope you’ll enjoy some of the photographs taken along the way.

red flowering gum (*Corymbia ficifolia*) infloresence just about to open

a petunia in an 18th Street garden - a friend saw this picture and declared it “goth” :)

Fall color on 19th Street - a maple hybrid (probably *Acer x freemani*)

a gold medallion tree (*Cassia leptophylla*) on 19th Street

a Monterey pine (*Pinus radiata*) in front of the Caselli mansion

A red flowering gum in the Castro neighborhood

Red Flowering Gums - San Francisco's Best Tree! Why have we stopped planting them?

July 17, 2024 by Michael Sullivan

Please join Jason Dewees, horticulturist at Flora Grubb Gardens and author of Designing with Palms, Mike Sullivan (author of Trees of San Francisco and webmaster of www.sftrees.com) and Richard Turner (retired editor of Pacific Horticulture) in declaring the last week of July as “red flowering gum week” in San Francisco. This amazing tree is in full bloom now - we need to start planting it again! Spread the word:

WHEREAS red flowering gum trees have stunningly beautiful red, orange, pink or white flowers every summer that outshine any other tree in San Francisco; and

WHEREAS mature red flowering gums are large trees with leaves that remain on the tree year-round, and so are excellent contributors to the fight against climate change; and

WHEREAS as natives of Western Australia, red flowering gums thrive in our cool coastal climate; and are one of the best adapted trees to San Francisco’s conditions;

WHEREAS the largest documented red flowering gum in Northern California, and the 2nd largest in the United States, is in San Francisco in San Francisco’s St. Francis Woods neighborhood in the Monterey Boulevard median near the intersection of Junipero Serra Boulevard; and

WHEREAS red flowering gums bloom from early July through September, but reach their peak bloom in late July;

WHEREAS the flowering season of red flowering gums coincides with peak tourist season in San Francisco, offering visitors Instagram-worthy brilliant floral displays;

WHEREAS, despite these many positive attributes, the City of San Francisco has virtually stopped planting red flowering gum trees;

NOW, THEREFORE, BE IT RESOLVED, that the many fans of this amazing tree declare the last week of July now and henceforth to be “Red Flowering Gum Week” in the City and County of San Francisco, dedicated to promoting the many advantages of, and sharing images and information about, San Francisco’s best tree!

in front of Mission High School in the Mission District

Monterey Boulevard in St. Francis Woods - this street is lined with red gums!

Southeast Bernal Heights Tree Tour

July 15, 2024 by Michael Sullivan

We return for a fourth walk on the slopes of Bernal Heights, this time to the southeastern corner of the neighborhood. Known for its mix of 19th, 20th, and 21st century residences, the neighborhood also offers dramatic views to the south and east, and a lively shopping district along Cortland Avenue. Despite the notoriously narrow streets, trees are common and diverse, including two that are “city champions” - the largest of their kind in the City.

Today’s walk begins at the northwest corner of Nevada Street and Cortland Avenue, and heads north (uphill) on Nevada to Powhattan Avenue, then east on Powhattan one block to Nebraska Street. Head south (downhill) on Nebraska to Cortland, and then east on Cortland for about half a block. The walk continues on the south side of Cortland on Bronte Street. (Be careful crossing Cortland as there is no crosswalk at this point; it may be safer to go further east and use the crosswalk at Bradford Street.) Head south (now, uphill) on Bronte to Jarboe Avenue, then west on Jarboe to Putnam Street, and north (downhill) on Putnam to Cortland. The walk ends one block west at Cortland and Nevada. This walk is about 1 ½ miles in length, with some moderately steep slopes.

Numbered trees are labeled with common and scientific names and country of origin, all written in white chalk on the sidewalk; accompanying numbers, in blue, run from 1 to 23. White arrows on the pavement provide directions whenever a turn is needed.

Nevada Street, Cortland to Powhattan, west side

1. 170 Nevada Sweetgum (Liquidambar styraciflua), E USA to Mexico & Central America

2. 147 Nevada Mock-orange or tobira (Pittosporum tobira), Japan & Korea (tree is across the street; clusters of intensely fragrant, white flowers; typically grown as a large shrub, this one is a city champion, largest in SF)

3. 134 Nevada Bronze loquat (Rhaphiolepis deflexa, syn. Eriobotrya deflexa), S China and Vietnam

4. 114 Nevada Santa Cruz Island ironwood (Lyonothamnus floribundus ssp. aspleniifolius), CA’s Channel Islands, except Catalina Island (this one is flowering heavily; others can be seen along Cesar Chavez Street, just north of Bernal Heights)

5. 104 Nevada Purple (or blue) potato bush (Lycianthes rantonnetii), Paraguay (typically a large shrub, this one has been trained into a multi-trunked, tree-like form; flowers are produced all year)

Powhattan Avenue, Nevada to Nebraska, south side

6. 900 Powhattan Champak (Magnolia champaca) S & SE Asia (small, magnolia-like flowers, appearing in summer, are intensely fragrant; these three trees have been pruned in an unfortunate manner)

7. 2 Nebraska Cabbage tree (Cussonia spicata), S Africa (tree is on Powhattan; a curious, uncommonly grown tree in SF; the palmately lobed leaves are distinctive; note the thick stems developing flower buds on the right-most trunk)

**Note this richly planted corner garden at Powhattan and Nebraska, created and maintained by the talented Elliot Goliger of Artisans Designs.

Nebraska Street, Powhattan to Cortland, west side

8. 2 Nebraska Jacaranda (Jacaranda mimosifolia), Argentina, Bolivia (the big show of blue purple flowers is just beginning, now that the leaves have fallen; these heat loving trees are becoming more common in SF, especially in warmer areas of the city—all thanks to climate change)

9. 2 Nebraska Hercules tree aloe (Aloidendron ‘Hercules’), hybrid of two S African species

10. 38 Nebraska Mediterranean fan palm (Chamaerops humilis), Mediterranean Basin: Portugal & Morocco to Tunisia & Italy (this is a young specimen that will grow into a low multi-trunked tree; northernmost natural range of any palm in the world)

11. 48 Nebraska Marina strawberry tree (Arbutus ‘Marina’), hybrid of Mediterranean species (first introduced in San Francisco; these two specimens are among the largest in the city)

12. 26 Nebraska Hybrid crape myrtle (Lagerstroemia hybrid.), Asia (watch for the flowers that will be opening soon, and for the glorious fall foliage color)

Cortland Avenue, Nebraska to Bradford, north side

13. 1410 Cortland Canary Island date palm (Phoenix canariensis), Canary Islands, Spain (a “grove” of three trees in this large yard; this is the species seen in the median of Upper Market Street and along the Embarcadero)

***Please cross Cortland carefully, perhaps using the crosswalk at Bradford Street, half a block to the east. Bronte Street is midway between Nebraska and Bradford, on the south side of Cortland.***

Bronte Street, Cortland to Jarboe, west side

14. 16 Bronte African fern pine (Afrocarpus falcatus, formerly A. gracilior), E & S Africa (this is the largest specimen in the city: a city champion)

15. 20 Bronte Queen palm (Syagrus romanzoffiana), S Brazil (one tall mature specimen and one much younger specimen)

16. 36 Bronte Elegant water gum (Tristaniopsis laurina ‘Elegant’), E Australia (this selection of the water gum has longer, glossier leaves than the species)

17. 62 Bronte Sweetshade tree (Hymenosporum flavum), E Australia (the fragrant yellow flowers appear in late spring through much of the summer; this tree often grows tall and narrow at first, eventually broadening its canopy)

Putnam Street, Jarboe to Cortland, east side

Giant bird-of-paradise (*Strelitzia nicolai*)

18. 77 Putnam Giant bird-of-paradise (Strelitzia reginae), E South Africa (note the huge, blue and white flowers on this young tree, compared to the much smaller, bright orange and blue flowers on the nearby common bird-of-paradise, which grows as a shrub)

19. 75 Putnam Washington thorn (Crataegus phaenopyrum) E USA (note the white flowers that will become colorful fruits in late fall, but beware of the long thorns on the branches)

20. 59 Putnam Mayten (Maytenus boaria), Chile (five trees with gracefully pendant branches, resembling those of weeping willows)

21. 42 Putnam Purple-leaf plum (Prunus cerasifera), Eurasia (two trees across the street) pink flowers usually appear by February; formerly SF’s most planted street tree; often seen without leaves through fall and winter)

22. 14 Putnam Glossy privet (Ligustrum lucidum), S China

Cortland Avenue, Putnam to Nevada, south side

23. 1302 Cortland Purple hopseed tree (Dodonaea viscosa ‘Purpurea’), native throughout tropical and subtropical parts of the world

Today’s walk ends here, kitty-corner from its beginning.

Grace Cathedral, decked out for Pride Month

Nob Hill Tree Tour (6-1-24)

June 01, 2024 by Michael Sullivan

For our 50th (!) chalk tree tour, we chose Nob Hill - one of the most iconic of the city’s many historic neighborhoods. Crowned by the magnificent 20th century Gothic-style Grace Cathedral, the hilltop is the home of the city’s finest hotels, the only Gilded Age mansion to survive the 1906 earthquake and fire (built by James Flood), and beautiful Huntington Park—a formal oasis in the heart of the city. As we chalked this tour on the first day of Pride Month, colorful flags and banners waved from all the hotels, along with rainbow-painted steps from Taylor Street up to the Cathedral’s main entrance, all in honor of the city’s diverse and inclusive culture. With the exception of the Flood mansion, all of the buildings in this predominantly residential neighborhood were built after the 1906 earthquake; the diversity of architectural styles is captivating. For such a dense neighborhood, trees are surprisingly plentiful and unexpectedly diverse.

Today’s walk is a simple one. It begins at the Interfaith Memorial Labyrinth at the top and to the side of the steps at Grace Cathedral, which is on Taylor Street between California and Sacramento streets. The Labyrinth is ringed with some particularly fine purple leaf plums (a Prunus cerasifera cultivar). From the Labyrinth, follow the walkway north towards the Canary Island date palm, which is tree #1. Once down at street level, head west on Sacramento past Jones Street to Golden Court. After exploring this fascinating pedestrian lane, continue west on Sacramento past Leavenworth Street to Kimball Place, another intriguing lane. Then, return to Leavenworth and head north to Clay Street, east on Clay to Taylor, and back south on Taylor to the Cathedral. Cross Sacramento and Taylor streets to enter Huntington Park for a delightful spot to sit and rest your feet. This walk is almost a mile and a half in length.

Grace Cathedral’s labyrinth, surrounded by purple leaf plum trees (*Prunus cerasifera*)

Numbered trees are labeled with common and scientific names and country of origin, all written in white chalk on the sidewalk; accompanying numbers, in blue, run from 1 to 24. White arrows on the pavement provide directions whenever a turn is needed.

Left to right: Jason Dewees, Mike Sullivan, Sairus Patel and Richard Turner (in front of a king palm - (Archontophoenix cunninghamiana)

The street addresses provided below will help when the chalk has faded. Most of the trees on this walk are planted in sidewalk pockets; a few are planted within the front or rear gardens of homes along the route. And a few are found in the quaint and curious dead-end lanes that are found in this neighborhood—reminiscent of the mythical Barbary Lane in Armistead Maupin’s Tales of the City.

2. 1230 Sacramento Marina strawberry tree (Arbutus ‘Marina’), hybrid of Mediterranean species (tree is across the street; first introduced in San Francisco)

**Note the beautifully shaped bougainvillea on the ornate building next door to 1230.**

3. N side of Cathedral Italian buckthorn (Rhamnus alaternus), Mediterranean Basin (this is typically a shrub but has been trained into a tree form here)

**Note the well-planted vertical garden, filled with a variety of ferns, on the north wall of the Cathedral School for Boys, just east of Jones.**

Sacramento Street, Jones to Golden Court, south side

4. 1155 Jones Indian laurel fig (Ficus microcarpa ‘Nitida’), southern Asia to N Australia (the entire block is planted with this tree, and other blocks as well; formerly one of SF’s most planted trees)

5. 1329 Sacramento Allspice magnolia (Magnolia x foggii), hybrid of two Asian species, M. figo and M. doltsopa (tree is growing in the narrow and dark gap between the buildings; despite the deep shade, it is flowering heavily; enjoy the intense fragrance of the white blossoms; it is likely a city champion)

a dragon guarding the trees on Golden Court

Golden Court, south of Sacramento

6. 10 Golden Lacebark tree (Brachychiton discolor), Eastern Australia (this rarely planted tree is 25 years old, and is a “City Champion” - the biggest of its species in San Francisco. We know of only one other lacebark tree in SF, so this was an unexpected and delightful surprise!

7. 8 Golden Iochroma fuchsioides, Andes of Ecuador and Columbia (typically known as a long-flowering shrub in SF, it will grow to tree-like dimensions in the Andes; it has no common name)

8. 9 Golden Lilly pilly tree (Syzygium smithii, previously known as Acmena smithii), E Australia (note the clusters of tiny white flowers and pale lavender fruits)

Karaka (*Corynocarpus laevigatus*) leaves

9. Golden Karaka (Corynocarpus laevigatus), New Zealand

10. Golden Douglas-fir (Pseudotsuga menziesii), West Coast & Rocky Mountains (tall conifer with needle-like leaves, almost hidden by all the shrubs; a CA native tree!)

**Continue west on Sacramento, past Leavenworth, to Kimball Place**

Kimball Place, south of Sacramento

11. South end of Kimball Cabbage tree or tī kōuka in Māori (Cordyline australis), New Zealand

Coast redwood (Sequoia sempervirens), Big Sur to SW Oregon; CA coastal native (2 trees rising out of this crowded space; this species is the tallest tree in the world)

Japanese maple (Acer palmatum), Japan, China, Korea

**Return to Leavenworth and head north**

Leavenworth Street, Sacramento to Clay, east side

12. 1202 Leavenworth Red-flowering gum (Corymbia ficifolia), SW Australia (produces bright red, orange, or pink flowers in summer; among the best and showiest of trees in SF’s urban forest; we cannot understand why the city is no longer planting this amazing tree!)

Mike, looking incredulous that the Public Works Department has banned the planting of SF’s most amazing tree!

13. 1228 Leavenworth Brisbane box (Lophostemon confertus), E Australia

14. 1250 Leavenworth River wattle (Acacia cognata), SE Australia

15. 120 Leavenworth King palm (Archontophoenix cunninghamiana), E Australia

One-sided bottlebrush (Calothamnus quadrifidus), Western Australia (this is usually a large shrub, not a tree; rarely seen in SF gardens)

Clay Street, Leavenworth to Jones, south side

16. 1385 Clay Olive (Olea europaea), Mediterranean Basin (4 young trees)

17. 1357 Clay Ginkgo (Ginkgo biloba), China (last of an ancient lineage of gymnosperms) Note that there is another ginkgo just past this one, and this 2nd ginkgo is a female, bearing malodorous fruits.

18. 1340 Clay Chitalpa (xChitalpa tashkentensis), hybrid of two native USA species, one from the SW deserts and one from the Midwest (3 small trees are in sidewalk pockets across the street; this hybrid species typically languishes in SF’s cool summer climate; reflected heat off the building appears to benefit these specimens; watch for soft lavender pink flowers later in the summer)

19. 1301 Clay New Zealand Christmas tree, pōhutukawa in Māori (Metrosideros excelsa), New Zealand (several trees on both sides of Clay and along Jones; this tree flowers most reliably in the summer months, which would be Christmas time in NZ, south of the equator)

Clay Street, Jones to Taylor, south side

20a. 1250 Jones Elegant water gum (Tristaniopsis laurina ‘Elegant’), E Australia (tree is on Clay; this selection of the water gum has longer, glossier leaves than the species)

20b. 1216 Clay Avocado tree (Persea americana), Mexico & Central America (a small tree is poking out of the entry courtyard of the building across the street)

21. 1217 Clay Pygmy date palm (Phoenix roebelenii), southern China, Laos, Vietnam

22. 1217 Coppertone Indian hawthorn (Rhaphiolepis ‘Coppertone’), hybrid of two E Asian species, Eriobotrya deflexa and Rhaphiolepis indica (3 round-headed trees across the street; new spring growth is coppery in color)

Taylor Street, Clay to Sacramento, west side

23. 1137 Taylor Chinese elm (Ulmus parvifolia), China, Korea, Japan, and Vietnam

Huntington Park, all sides

24. Huntington Park block London plane tree (Platanus x hispanica, formerly Platanus acerifolia), hybrid of E USA species and European species (this tree surrounds the park, and there are many more throughout the neighborhood, almost all of them pollarded as this one is; this hybrid species is among the most commonly planted tree in cities around the world).

25. Huntington Park, south side Ray Hartman ceanothus (Ceanothus ‘Ray Hartman’), hybrid of CA native species (clusters of soft blue flowers in winter/early spring). This one is one of the largest we know of in San Francisco - it may be a “City Champion”!

Today’s walk ends here. Take time to enjoy the quiet beauty of Huntington Park, where there are a variety of other trees, including a number of blackwood acacias (Acacia melanoxylon) and a stunning specimen of Ray Hartman ceanothus (Ceanothus ‘Ray Hartman’) next to Mrs James Flood’s fountain in the southeast corner of the park.

Bunya bunya in West Portal Removed by Owner - Another one of SF's Best Trees is Gone

March 26, 2024 by Michael Sullivan

Another very sad story for San Francisco tree lovers - the majestic bunya bunya tree (Araucaria bidwillii) at 201 Vicente Street in the West Portal neighborhood, has been removed by the owner. Nothing left but a stump. I don’t have the details as to why, but I do know it was done without a permit - which is a no no, since the tree was a “significant tree” that was close enough to the sidewalk to require a City permit for removal. The Public Works Department is aware of the violation and will be dealing with the owner.

This is the second of San Francisco’s “top 10” trees to be lost within the last year - the amazing California buckeye at Willard Street North and McAllister died of unknown causes last winter, and now this. I previously ranked the California buckeye as my #2 in the City and this bunya bunya was #4. Both trees are highlighted in my Trees of San Francisco book. So sad to lose these two landmarks!

Trees of Angel Island (2-24-24)

February 26, 2024 by Michael Sullivan

I did a bike trip to Angel Island today, not thinking I would see a lot of tree diversity. As expected, the island is full of coast live oaks, toyon and the occasional California buckeye and California bay. But what I didn’t expect was to find some unusual specimen trees near the Angel Island Immigration Museum.

To get to the immigration museum, you head downhill from the Perimeter Road at a point on the northeast part of the island. On the walk down, on your left you’ll see a couple of stately spotted gums (Corymbia maculata).

Continue down the road to the open area below the museum, and to your far left is a large bunya bunya tree tree (Araucaria bidwillii), native to Australia. Bunya bunyas are rare in San Francisco, and one of our best was just cut down in West Portal at Vicente and Wawona, so this was a welcome sight.

bunya bunya tree (*Araucaria bidwillii*)

At the other end of the clearing near the museum is a close relative of the bunya bunya - a Norfolk Island pine (Araucaria heterophylla), also large and mature. It wouldn’t surprise me if they were planted at the same time.

And in between the two Araucaria, facing the water, two Canary Island date palms (Phoenix canariensis).

Angel Island used to be full of blue gum eucalyptus trees (Eucalyptus globulus), but 80 acres of eucalyptus were removed in the 1990s - among other things, they were thought to be a fire hazard that created risk for the nearby historic buildings. However, there are still beautiful specimens of this tree to be found around the island.

blue gum eucalyptus (*Eucalyptus globulus*)

And lastly, the most common tree on the island - coast live oak (Quercus agrifolia).

Trees of Mexico City (1-25-24)

February 13, 2024 by Michael Sullivan

I visited Mexico City with my family in late January 2024 - we stayed in the Roma Norte neighborhood, and didn’t stray very far from there, so this blog may not be representative of the entire city’s trees.

It was my first time in Mexico City. I had heard that the city was very leafy, and I found that to be accurate. In fact, at least in the Roma Norte neighborhood, the street trees are so dense that it’s not easy to get an Instagram-worthy photo of an individual tree! This link from Google maps of a street not far from our hotel will give you a sense of this part of Mexico CIty.

We visited one of the city’s botanical gardens (Jardin Botanico del Bosque de Chapultepec), but I found it underwhelming. The cactus and agave collections were attractive, but the park is relatively small (13 acres), and very few tree specimens were labeled.

The three species that dominated the streets of our neighborhood were shamel ash (Fraxinus uhdei), glossy privet (Ligustrum lucidum) and American sweetgum (Liquidambar styraciflua). Two of the three are native to Mexico - shamel ash is native from west-central Mexico to Costa Rica, and sweetgum is found in disjointed areas from central Mexico to Nicaragua.

The ash trees were the most abundant of all, which saddened me a bit to think that the emerald ash borer is marching across the continent, killing every ash it encounters, and eventually I suspect will make it to Mexico City.

shamel ash (*Fraxinus uhdei) - closeup of leaves and samaras (fruits)*

glossy privet (*Ligustrum lucidum*) - closeup

American sweetgum (*Liquidambar styraciflua*) - closeup of leaves

Another tree that was very common on city streets was weeping fig (Ficus benjamina). It’s very rare as a street tree in my native San Francisco, but I saw it everywhere in Mexico City.

weeping fig (*Ficus benjamina*) - closeup

Occasionally I ran across orchid trees (Bauhinia purpurea) in bloom as street trees.

Not a tree, but another plant I saw everywhere in our neighorhood was split leaf philodendron (Thaumatophyllum bipinnatifidum).

When we ventured out of Roma Norte into other neighborhoods, the canopy thinned out a bit (and I also started to see some more unusual tree species. Below is a Cook pine that we encountered in the Condesa neighborhhood, not far from the city’s botanical garden. This tree always leans towards the equator (a discovery by botanist Matt Ritter in 2017), and this one was duly leaning south!

Cook pine (*Araucaria columnaris*) on Calle Juan de la Barrera near the corner of Avenida Mazatlan in the Condesa neighborhood

We visited Casa Gilardi, a home designed by minimalist architect Luis Barragan-designed - the family that has owned it since it was built it gives private tours. It’s in the San Miguel Chapultepec neighborhood, and if you’re into architecture or home design, I really recommend it. Inside the open air courtyard of the home is a large jacaranda (Jacaranda mimosifolia), a tree native to Argentina and Bolivia - but very popular in Mexico City.

jacaranda (*Jacaranda mimosifolia*) in the courtyard at Casa Gilardi

A couple of days later I saw what I think it the largest jacaranda I’ve ever seen - the address is 208 Jalapa in the Roma Norte neighborhood.

a huge jacaranda (*Jacaranda mimosifolia*) at 208 Jalapa in Roma Norte

At 7,350 feet in altitude, Mexico City isn’t tropical, but since it rarely has freezing temperatures, there are lots of palm trees that do well here. Canary Island date palms (Phoenix canariensis) were pretty common.

And not far from our hotel (at the intersection of Calle Jalapa and Calle Puebla in Roma Norte), we found a corner full of bismarck palms (Bismarckia nobilis), a tree native to Madagascar.

Compared to my native San Francisco, there were relatively few eucalyptus trees. We did see a beautiful eucalyptus relative - a spotted gym (Corymbia maculata) on Avenida Insurgentes Sur near Avenida Alvaro Obregon in Roma Norte.

spotted gym (Corymbia maculata) - Avenida Insurgentes Sur

Bailey's Acacia - first sign of a San Francisco Spring!

February 09, 2024 by Michael Sullivan

It’s a little late this year - normally this tree blooms in January in San Francisco. Bailey’s acacia (Acacia baileyana) is a tree from eastern Australia that blooms with striking yellow flowers. It’s the first of our trees to bloom - next will be the plum trees (later in February), then the cherries (March), and even later (April/May) the hawthorns.

As you can see from the partially hidden street sign, this tree is at the corner of 17th and Shrader Streets in the Cole Valley neighborhood.

And it has one more claim to fame - this tree was the one photographed by author and botany professor Matt Ritter for his (fantastic) book “A Californian’s Guide to the Trees Among Us”.

Fairmount Hill Tree Tour (2-3-24)

February 05, 2024 by Michael Sullivan

Between showers on a mostly windless day, we chose a relatively quiet neighborhood wedged between the northeastern extent of Glen Park and the southern extent of Noe Valley. It covers the lower slopes of a hill known as Fairmount, one of the many hills that make up the San Miguel Hills in this part of the city. We were pleased with the diversity of trees in this small neighborhood. But, the real draw is the variety of residential architecture, from stunning and beautifully restored Victorians to modest cottages, along with some ‘50s-‘60s apartment buildings. Laidley Street is known for its collection of radical contemporary architecture from the ‘80s and ‘90s. Take time to appreciate this diversity in residential design.

Today’s walk is a simple one. It begins on Whitney Street, at its terminus at Chenery Street. It heads north on Whitney for two blocks to Randall Street, then continues on Randall for two more blocks to Harper Street, and heads uphill on Harper to Laidley Street. From there it heads southeast-ish on Laidley to Miguel Street, downhill on Miguel to Whitney, and then north again on Whitney for a few yards. This walk is almost a mile and a half in length.

Numbered trees are labeled with common and scientific names and country of origin, all written in white chalk on the sidewalk; accompanying numbers, in blue, run from 1 to 34. White arrows on the pavement provide directions whenever a turn is needed.

Whitney Street, Chenery to Fairmount, east side

1. 298 Chenery Brisbane box (Lophostemon confertus), E Australia (tree is on Whitney)

2. 263 Whitney Cajeput tree (Melaleuca quinquenervia), New Caledonia, New Guinea, E Australia (3 trees, including 1 across the street; feel the distinctive spongy bark)

3. 249 Whitney Ginkgo (Ginkgo biloba), China (last of an ancient lineage; there are many ginkgos in the neighborhood, including some very young ones on Miguel)

4. 249 Whitney Chinese elm (Ulmus parvifolia), China, Korea, Japan, and Vietnam

5. 229 Whitney African fern pine (Afrocarpus falcatus, formerly A. gracilior), E & S Africa (peeking around the construction fence)

6. 219 Whitney Victorian box (Pittosporum undulatum), E Australia (common in the neighborhood; intensely fragrant white flowers cycle through the year)

7. 191 Fairmount Tree fuchsia (Fuchsia arborescens), C America (peeking over the fence on Whitney; this large shrubby fuchsia flowers all year in SF)

8. 191 Fairmount Peppermint willow (Agonis flexuosa), SW Australia (2 trees is on Whitney)

Whitney Street, Fairmount to Randall, east side

9. 159 Whitney Water gum (Tristaniopsis laurina), E Australia (this tree grows in stream-side locations in the wild, hence the common name; SF’s most commonly planted street tree)

10. 155 Whitney Mayten (Maytenus boaria), Chile

11. 119 Whitney Coast redwood (Sequoia sempervirens), Big Sur to SW Oregon; CA coastal native (this species is the tallest tree in the world)

12. 197 Randall Plume albizia (Paraserianthes lophantha, formerly Albizia lophantha), SW Australia (within the fenced garden of the property on Randall; a feathery-leafed small tree with pale yellow flowers in clusters; this species has become a weed in the western portions of Golden Gate Park and above Sutro Baths)

**Cross Whitney and continue a short distance on Randall**

Randall Street, Whitney to Sanchez, south side, then north side

13. 201 Randall Ray Hartman ceanothus (Ceanothus ‘Ray Hartman’), hybrid of CA native species (just beginning to open its blue flowers)

14. 207 Randall Indian laurel fig (Ficus microcarpa ‘Nitida’), S Asia to N Australia (formerly one of SF’s most planted trees)

**Cross Randall**

15. 200 Randall Brazilian pepper tree (Schinus terebinthifolia), Brazil, Argentina, Paraguay

16. 228 Randall Lemon bottlebrush (Callistemon citrinus), E Australia

17. 228 Randall Giant yucca (Yucca gigantea, formerly Y. elephantipes), Mexico & Central America

18. 240 Randall New Zealand Christmas tree, pōhutukawa in Māori (Metrosideros excelsa), New Zealand (this tree flowers most reliably in summer months, which would be Christmas time in NZ, south of the equator)

Randall Street, Sanchez to Harper, north side

19. 250 Randall Olive (Olea europaea), Mediterranean Basin

20. 250 Randall Meyer lemon (Citrus x meyeri), hybrid of mandarin and pomelo, both SE Asian species (in the rear yard, heavily laden with fruit)

21. 270 Randall Sweet viburnum (Viburnum odoratissimum), S, SE, and E. Asia (very uncommon in SF; usually a shrub)

** Cross Harper**

Harper Street, Randall to Laidley, west side

22. 76 Harper Bailey’s acacia (Acacia baileyana ‘Purpurea’), E Australia (this is usually among the earliest flowering trees in SF, always beginning in January with fluffy bright yellow flowers)

** Cross Laidley**

Laidley Street, Harper to Fairmount, south side

23. 128 Laidley Chinese windmill palm (Trachycarpus fortunei), China (a fine specimen)

24. 117 Laidley Texas privet (Ligustrum japonicum ‘Texanum’), E. Asia (2 trees across the street; city champions; these are usually seen as large sheared hedges)

25. 138 Laidley Cork oak (Quercus suber), Spain & Portugal (3 trees; the bark of this tree provides the cork used in wine bottles)

Cork oak (*Quercus suber*) - closeup of bark

26. 140 Laidley Black locust (Robinia pseudoacacia), E USA (this deciduous tree will have fragrant white flowers in spring)

** continue on the lower side of Laidley**

Laidley Street, Fairmount to Miguel, east side (lower side)

a beautiful Victorian home on Laidley Street

27. 237 Fairmount Willow-leaf peppermint (Eucalyptus nicholii), SE Australia (2 trees, one on each side of Laidley)

28. 233 Laidley Primrose tree (Lagunaria patersonii), Norfolk and Lord Howe islands (soft pink flowers will appear later in the year)

29. 224 Laidley Rusty-leaf fig (Ficus rubiginosa), E Australia (across the street)

30. 279 Laidley Glossy privet (Ligustrum lucidum), S China (2 trees)

Miguel Street, Laidley to Whitney, northeast side

31. 201 Miguel Tree aloe (Aloidendron barberae, formerly Aloe bainesii), S Africa to Mozambique (this specimen appears to be variegated, but the effect is due to sunscald)

32. 219 Miguel Bronze loquat (Rhaphiolepis deflexa, syn. Eriobotrya deflexa), S China and Vietnam

Whitney Street, north from Miguel, west side

33. 268 Whitney Jacaranda (Jacaranda mimosifolia), Argentina and Bolivia (watch for the big show of blue purple flowers in summer; these heat loving trees are becoming more common in SF, especially in warmer areas like the Mission District—thanks in partto climate change)

34. 260 Whitney Marina strawberry tree (Arbutus ‘Marina’), hybrid of Mediterranean species (many fine specimens of this tree can be seen throughout the neighborhood; first introduced in San Francisco)

Today’s tree walk ends here, just a few yards north of its beginning at Whitney and Chenery.

Our regular commercial: This walking tour was organized by Mike Sullivan, author of The Trees of San Francisco and webmaster of www.sftrees.com; Jason Dewees, horticulturist at Flora Grubb Gardens and author of Designing with Palms; Richard Turner, retired editor of Pacific Horticulture magazine and Sairus Patel, soon to be author of Trees of Stanford and Environs. You can follow Mike and Jason on their tree-themed Instagram pages at @sftreeguy and @loulufan. Richard edited another great book on San Francisco trees: Elizabeth McClintock’s Trees of Golden Gate Park. If you’re a tree enthusiast, buy all four of these books!

Pacific Heights West Tree Tour

December 10, 2023 by Michael Sullivan

On a crisp December morning, we returned to the western end of Pacific Heights, a neighborhood filled with well-kept Victorian homes, a delightful shopping district, one of the finest branch libraries in the city, and one of the few remaining single-screen movie houses (the Vogue) in town. For this tour we were happy to be joined by Josh Gevertz, Arboretum Director at Cypress Lawn Cemetery in Colma (home to some amazing trees - it was recently recognized as a Level I arboretum by Morton Arboretum’s international ArbNet program - take the virtual tree tour here).

Today’s walk begins in front of the elegant Presidio Branch Library, at 3150 Sacramento Street, and heads east on Sacramento to Baker Street, south on Baker to Pine Street, east on Pine to Lyon Street. The walk then turns south on Lyon for half a block, crosses Lyon to the east side, then heads north on Lyon to Sacramento, and finally east on Sacramento back to the Library. This walk is a little over one mile in length.

Numbered trees are labeled with common and scientific names and country of origin, all written in white chalk on the sidewalk; accompanying numbers, in blue, run from 1 to 25. White arrows on the pavement provide directions whenever a turn is needed.

Sacramento Street, Lyon to Baker, north side

1. 3150 Sacramento Flame tree (Brachychiton acerifolius), E Australia (a bold allee of six trees at the Presidio branch library; trees may lose their leaves just before flowering)

Baker Street, Sacramento to California, west side

2. 1819 Baker Southern magnolia (Magnolia grandiflora), SE USA (many in this block)

3. 1817 Baker Little Gem magnolia (Magnolia grandiflora ‘Little Gem’), SE USA (this selection of southern magnolia has smaller leaves, smaller flowers, and matures at a smaller size; compare with #2)

4. 1815 Baker Japanese maple (Acer palmatum), Japan, China, Korea (these trees have been pruned into a loose hedge lining the edge of the front garden)

5. 1813 Baker Brush cherry (Syzygium australe, formerly S. paniculatum), E Australia

6. 1813 Baker Irish yew (Taxus baccata ‘Fastigiata’), Irish cultivar of Eurasia & N Africa parents

7. 1811 Baker Eastern dogwood (Cornus florida ) E North America (not always the best choice for coastal California, but this one already has flower buds for next spring)

California Street, west of Baker, north and south sides

8. 3000 California Indian laurel fig (Ficus microcarpa ‘Nitida’), S Asia to N Australia (formerly one of SF’s most planted trees)

9. 3001 California Fastigiate blue Atlas cedar (Cedrus atlantica ‘Glauca Fastigiata’), Atlas Mountains of Morocco & Algeria (note the narrow upright habit of the branches)

Blue Ice yellowwood (Podocarpus elongatus ‘Monmal’), S Africa

Baker Street, California to Pine, west side

10. 1710 Baker Chinese windmill palm (Trachycarpus fortunei), China (across the street)

11. 2896 Pine Peppermint willow (Agonis flexuosa), SW Australia (tree is on the east side of Baker)

Baker Street, Pine to Bush, west side

12. 1653 Baker Modesto ash (Fraxinus velutina ‘Modesto’), SW North America (this cultivar discovered in Modesto, CA)

13. 1611 Baker London plane tree (Platanus x hispanica, formerly Platanus acerifolia), hybrid of E USA species and European species; it is among the most commonly planted trees in cities around the world; there are many in this neighborhood)

14. 1611 Baker Japanese maple (Acer palmatum), Japan, China, Korea (one of the largest in the city)

15. 1611 Baker Australian tree fern (Sphaeropteris cooperi, formerly Cyathea cooperi), SE Australia

Bush Street, Baker to Lyon, north side

16. 2810 Bush Prickly melaleuca (Melaleuca styphelioides), E Australia (note the tiny prickly leaves and spongy park; white flowers appear in summer; this is one of the biggest in town)

Lyon Street, south of Bush, west side

17. 1515 Lyon Carob (Ceratonia siliqua), E Mediterranean Basin (there are several trees in this block; seed pods can be used to make a chocolate substitute—though not recommended for true chocolate lovers)

18. 1511 Lyon Monterey cypress (Hesperocyparis macrocarpa), Carmel, CA, native (one of the most widely planted conifers in coastal California; note the trunk is covered with English ivy, which should be removed for the health of the tree)

tree-themed art at Little School (1520 Lyon)

** cross the street carefully**

Lyon Street, south of Bush, east side

19. 1590 Lyon Victorian box (Pittosporum undulatum), E Australia (intensely fragrant white flowers cycle through the year)

Lyon Street, Bush to Pine, east side

20. 1644-46 Lyon Holm oak (Quercus ilex), Mediterranean Basin (a surprisingly uncommon tree in SF, despite its adaptability to our climate; these 2 trees are city champions)

21. 1652 Lyon Italian bay tree or Grecian laurel (Laurus nobilis), Mediterranean Basin (leaves of this tree are the bay leaves used in cooking)

Lyon Street, Pine to California, east side

22. 2296 Pine Glossy privet (Ligustrum lucidum), S China (tree is on Lyon)

23. 1740 Lyon Marina strawberry tree (Arbutus ‘Marina’), hybrid of Mediterranean species (many fine specimens of this tree can be seen throughout the neighborhood; first introduced in San Francisco)

Lyon Street, California to Sacramento, east side

24. 1812 Lyon Chinese elm (Ulmus parvifolia), China, Korea, Japan, and Vietnam

Sacramento Street, Lyon to Baker, south side

25. 1832 Lyon Olive (Olea europaea), Mediterranean Basin (trees are on Sacramento)

Today’s tour ends here on Sacramento, across the street and a few doors west of the Presidio Branch Library, where it began.

Top photos of this blog's first decade!

November 05, 2023 by Michael Sullivan

I noticed recently that this blog just had a 10 year anniversary - my first post was August 30, 2013. I scrolled through the decade of posts, and found some photos that made me smile. Here are my top sftrees.com photos from the last 10 years: