Spring must be here - Acacia baileyana in bloom

Bailey's acacia - southwest corner of Grattan and Shrader Streets in Cole Valley

I've been doing a "Cole Valley Tree of the Month" series for some time in the Cole Valley Facebook group, and when I walked by this tree yesterday at the corner of Grattan and Shrader Streets in Cole Valley, I grabbed my iPhone, shot this picture and made it the "Cole Valley tree of January" - only to be reminded that it happened to be the first of February!   It's just that I associate this tree - Bailey's acacia, or Acacia baileyana, with January blooms.   Bailey's acacia is the first tree to bloom in the spring (after 30 years in San Francisco, it still seems weird to me to call January “spring”), and the brilliant yellow flowers are eye-catching. The tree is native to Australia, where it’s called “Cootamundra wattle”, as it's native to Cootamundra, New South Wales, just west of Canberra.  (The town holds a 'Wattle Time' festival every year when the trees start to bloom.)  

Acacias do put out a good amount of pollen, but the pollen is only mildly allergenic, and it's heavy, which means it exists only in the immediate vicinity of the trees.   You're much more likely to suffer allergies from oaks, elms, pines, and and other wind-pollinated trees - the inconspicuous flowers of those trees don't get noticed, but they put out great quantities of lightweight pollen.   Trees with colorful flowers aren't as likely to cause allergic reactions since the pollen is heavy and sticky (it's designed to stick to insect pollinators, who are attracted by the flower's color).     

New Zealand Trip

Monterey cypress north of Auckland, New Zealand

Just got back from a 2 week trip to New Zealand - it's been my #1 "bucket list" place for a long time.   I was especially excited to see trees that are San Francisco street trees (New Zealand Christmas trees, giant dracaena, tea trees, etc.) in their native habitat.  

One thing I noticed was LOTS of Monterey cypress (Cupressus macrocarpa) and Monterey pine (Pinus radiata, which the New Zealanders call "Radiata pine") in the countryside, used as windbreaks, shade for sheep and other livestock, accent trees, etc.  Which made big parts of the countryside look a lot like California!  There were also many stands of Monterey pine used used as lumber trees - without any evidence of pine canker that i could see.  

Northern hemisphere conifers (Douglas fir is a prominent example) have become naturalized in big parts of New Zealand, and have become invasive pests, taking over entire landscapes.  Interestingly, our Monterey pine and Monterey cypress are not invasive, because the cones of the tree typically only open and disburse their seeds where there is fire or extremely hot weather.   

New Zealand Christmas tree in the Bay of Islands, New Zealand

I spent three days hiking through native beech forest on the Routeburn Track on the South Island.  It was very cool to see forests composed almost entirely of  different species of Nothofagus (a cousin of our northern hemisphere beeches) because they were so new to me (the only Nothofagus I can remember seeing here in CA was a giant specimen at Filoli, south of San Francisco).  One cool tree I encountered along the way:  the tree fuchsia - Fuchsia excorticata, the world's largest fuchsia, with distinctive papery bark (and recognizable fuchsia flowers).   

Of course, I made a point to find New Zealand Christmas trees (Metrosideros excelsa) on the North Island, although sadly by the time we got there on January 2, they were almost all out of bloom (these native trees seemed to be strict about blooming at Christmas time).   They're called by the Mauri name "Pohutukawa" in New Zealand, and the New Zealanders were very surprised to find that they were popular street trees in San Francisco.  

Aerial roots on a New Zealand Christmas tree in Gisbourne, North Island, New Zealand

Sadly we didn’t get to see any Nikau palms (New Zealand's only native palm, and one of my favorites of the palms) in their glory - saw a few of them planted as street trees (!) in Whangarei in the north island, and every once in a while saw one in the kauri forest on the west side of the north island.  I was surprised to find that the best places to see them in New Zealand were on the west side of the cooler south island.

It was a great trip - New Zealand is a great place to visit for many reasons, and interesting trees is definitely one of them!    

Floss silk tree in the Mission

A Ceiba speciosa 'Majestic beauty' (floss silk tree) in bloom at the edge of the new park (used to be a parking lot) at Shotwell/17th/Folsom in the Mission.  The tree and others nearby were planted in 1997.   The species normally doesn’t do very well in San Francisco - it is much happier (and more common) in Southern California. 

SF Magazine Article

Great SF Magazine article by Lynn Rapoport, a tree wonk who's also a great freelance journalist.   She does a great job explaining why it's fun and satisfying to learn about our urban forest!

Ceanothus in bloom

Ceanothus seems to be in bloom all over the city as I write (early April 2017).   There are 50 or so speciesof Ceanothus, but very few that can be trained as a tree.  Ceanothus 'Ray Hartman" is one - it's a hybrid (cross) between two parent species: Ceanothus arboreus from Catalina Island in southern California, and the northern California Ceanothus griseus.  It’s the only Ceanothus planted as a street tree in San Francisco, and one of the very few California natives that you’ll see planted in sidewalk cuts on the street (along with Catalina ironwood).  

These trees in Cole Valley at the corner of Waller and Cole are some of the best in San Francisco.

(And I wish I knew who this "Ray Hartman" was/is - doesn't seem to be any info on the web about him.   Let me know if you know!

Corner of Waller Street and Cole Street in San Francisco

Azores Trees

Just got back from a week in the Azores - Sao Miguel and Terceira islands.   The Azores are Portuguese islands in the middle of the Atlantic Ocean - 800 miles west of Portugal, and about 2000 miles east of Boston - volcanic islands, with a mild, San Francisco-like climate (coastal, rarely above 80 degrees fahrenheit, and rarely below 45 degrees).  

New Zealand Christmas tree - Ponta Delgada in Sao Miguel Island, Azores

It was interesting to see so many introduced trees in the Azores that are also popular as ornamentals here in San Francisco.   Metrosideros excelsa (New Zealand Christmas tree - see photo above) is often used in the Azores as an ornamental, but it has also naturalized in the forests of the islands (which I’ve never seen here in California).   The New Zealand Christmas tree in the photo above was a huge specimen in Ponta Delgada, the capital city of the Azores - so big that it had supports to hold up its limbs - if you look carefully you'll see the many vertical steel supports.    Trees from the Araucaria genus are everywhere as specimen trees -- especially Norfolk Island Pine trees (Araucaria heterophylla).  (The Norfolk Island Pine in the photo below was a young specimen just outside our hotel window in Angra de Heroismo, the largest city on Terceira Island- the hotel was in an early 1600s stone fort built by the Spanish during a 40 year period when they controlled the islands).   And Pittosporum undulatum (Victorian box) is everywhere as a naturalized tree - to the point where there were forests of the tree - it has become an ecological problem on the islands.

Norfolk Island Pine - Angra de Heroismo on Terceira Island

There are trees that are native to the Azores - in fact endemic to them (which means that they found in nature only in the Azores).  It was interesting to see native species that were closely related to trees I recognized, but which had developed into separate species as a result of the physical isolation of the islands.  Laurus azorica, for example, was obviously a close relative of the Grecian bay (Laurus nobilis) that is found on San Francisco streets.  

Because the Azores were isolated from Europe and North America for millions of years before the Portuguese arrived in the 1400s, the trees and plants evolved separately from their cousins in Europe and North America - which explains why there are so many unique species here. It also explains why introduced species from elsewhere are such a problem - the introduced species have no natural pests or diseases, and so they can out-compete the natives. Interestingly, Azores plants have been creating ecological troubles on other islands after being introduced - for example, the Azores’ evergreen fire tree (Myrica faya) is the main species to have regenerated on old lava flows in the islands. It was introduced to the Hawaiian islands, where it has threatened local flora there. (By the way, the Azores reminded me of the Hawaii islands with cooler weather - the island groups are both verdant, volcanic and isolated from other land masses.)

London plane trees (Platanus X acerifolia) line the roads everywhere in the Azores.   The trees below were on a back road on Terceira island.

By the way, I highly recommend a visit to Parque Terra Nostra, a botanical garden near Furnas on San Miguel Island. The buildings here date to the 1700s, when Thomas Hickling, a wealthy Boston trader, built a home and introduced a number of trees and plants from North America. Subsequent generations of Azorean owners expanded the collection. In addition to a garden filled with endemic and native Azorean plants, there are beautiful plants and trees from other Mediterranean and semitropical areas of the globe, including trees from the Araucaria and Metrosideros genera, eucaplytus, redwoods, tree ferns, various palm species, and huge rhododendrons, magnolias, hydrangeas and camellias.

My favorite tree in the garden (and it was a surprise to see it) was a Wollemi pine (Wollemia nobilis). This is a tree botanists thought had been extinct for millions of years (they only knew it from fossil records) - until David Noble, an Australian hiker with some botanical knowledge, noticed some trees in a remote ravine in Wollemi Park, 200 miles from Sydney Australia. He brought some cuttings to scientists in Sydney, who concluded that Noble had discovered a “living fossil” - somehow, the 100 or so trees in that ravine had managed to survive - the last remaining specimens of their species. (Imagine if a hiker in a remote New Guinea valley had discovered a stegosaurus - it was like that for botanists.) Here’s a photo of me, next to the tree in the garden - not that it’s not very big, since no garden in the world has had one of these for more than 25 years!

Wollemi pine in Parque Terra Nostra

Yes On Prop E for Trees!

I've been a San Francisco tree advocate for a long time.   I serve on the City's Urban Forestry Council; authored Trees of San Francisco,  and have a 25+ years with Friends of the Urban Forest as volunteer and past board member and board president.   In all of my years of tree advocacy, there's never been anything on the election ballot as important to our city's urban forest as this November's Proposition E - and big kudos to Supervisor Scott Wiener for his leadership in bringing it to the ballot..   

The biggest problem with San Francisco's trees has always been the lack of care and maintenance.  We're doing a good job of planting trees, thanks to groups like Friends of the Urban Forest.  But we do a miserable job of caring for them.  The city makes residents pay for pruning their trees - but most residents either don't know that, or can't afford to pay for tree care.   The result is trees that are unhealthy, look terrible, and in many cases are dangerous.    

Prop E would shift all responsibility for tree care and sidewalk repairs to the City, where it belongs, ensuring that our trees receive regular, periodic pruning and care from trained professionals.   VOTE YES ON PROP E!   And be sure to like the Facebook Page for Prop E!

My Favorite Tree

I'm often asked about my favorite tree.  Not the type of tree I love most, but my favorite individual tree in San Francisco.   This tree, at 1221 Stanyan Street in Cole Valley, is my personal #1, and it's in full bloom right now (it's Memorial Day 2016 as I write; I took the photos below yesterday).

Yellow New Zealand Christmas Tree - 1221 Stanyan Street

This tree is one of the city’s best specimens of New Zealand Christmas tree (Metrosideros excelsa), popular for its showy red bottlebrush flowers. And, indeed, all of the many hundreds of New Zealand Christmas trees on San Francisco’s streets have red flowers, except for one—at 1221 Stanyan. Every year around this time, that tree pops with spectacular yellow flowers.

How did this tree end up with yellow flowers? The story goes back to Victor Reiter, San Francisco’s most famous plantsman from the 1940s until his death in 1986. In 1940, there was a natural mutation of the species on tiny Motiti Island in the Bay of Plenty in New Zealand, and Reiter was one of the first Californians to obtain a cutting. As the Reiter family lived in several homes in a three-block stretch of Stanyan Street, they planted the curiosity in front of their 1221 Stanyan address—still occupied today by a family member. And more than 70 years later, the tree is thriving. It’s a beautiful mutant with an amazing history and pedigree—and my favorite tree in San Francisco.

Bunya Bunya

This sign is in the park at the base of Hyde Street in Fisherman's wharf, where there's a grove of bunya-bunya trees.  Seed pods from bunya-bunyas can weigh up to 15 pounds (the record is a 17-pounder).   In early October, a seed pod from this grove fell and hit a tourist, causing some significant damage.  The trees are now fenced off.  

Some Spring Flowers

I was out this weekend, and saw some great Springtime flowers - all on Parnassus Avenue near Cole Street.   And all from Australia! Two types of bottlebrush, and a fragrant sweetshade tree.   Enjoy!

Sweet shade (hymenosporum flavum)

Weeping bottlebrush (callistemon viminalis)

Lemon bottlebrush (Callistemon citrinus)

Sunnyside Conservatory

I've known about the Sunnyside Conservatory for some time - it's a Victorian-era conservatory at 236 Monterey Boulevard with a long history - abandoned by its original owners, the lot at one point was so overgrown that a subsequent buyer of the lot had no idea that the conservatory was even there - it had been overgrown by vegetation.   But I also knew that there were some unusual trees on the property, so last weekend I wandered by to check it out.

I found some interesting stuff - one of the city's largest and most mature wine palms (Jubaea chilensis).  On the steps up to Joost Street is a stunning Caracas wiganida (Wigandia urns) - with giant, showy purple flowers - only the 2nd one I've found in San Francisco.   And to the right as you face the conservatory is some kind of Banksia - in the protea family, with unusual yellow flowers.   

Banksia flower

Chilean wine palm (Jubaea chilensis)

Wigandia urens

Victorian Box Blooms Out En Masse

The Victorian box (Pittosporum undulatum) is one of San Francisco's most common trees, and small white flowers of the tree are out all over the city - as usual in late February/early March.   They aren't conspicuous visually, but they have the strongest fragrance of any common tree in San Francisco, and when they emerge en masse, they can fill entire blocks with their orange blossom-like perfume.   It's a smell that I associate strongly with San Francisco, as I've never seen any city that has this tree more densely than SF.   One of my first memories of San Francisco was walking down Hyde Street, preparing to turn on Pine  to walk downtown to my first job, and smelling the Victorian Box trees around the corner before I saw them!

The flowers of this Australian native are followed by groups of small green fruits, which they turn yellowish, then orange, and finally break open dropping a sticky mess on whatever's below.   As a result, the tree has dropped in popularity a bit, with some trying the sweetshade tree (Hymenosporum flavum) instead.   Sweet shade is another Australian tree

Red Flowering Gums at Peak

My brother was in town from upstate New York a couple of weeks ago - his first time here in 25 years.   Like me when I first arrived 30 years ago, he wasn't familiar with California trees - and it was the red flowering gum that most captured his attention.   "What's that tree?", he asked as we passed this specimen, on the north side of 17th street between Cole and Shrader.    I wasn't surprised – the red flowering gum (Corymbia ficifolia) is one of San Francisco’s most striking trees, and the flowers peak in July and August.  The tree has clusters of brilliant red, pink, orange, or white flowers.  It can’t be easily reproduced from cuttings, and when it is reproduced from seed, nature rolls the genetic dice, so the flower color rarely matches that of the parent tree. Large, smooth, and woody seed capsules (which look like the bowl of a pipe) form after the flowers and hang onto the tree for many months, often until the next year’s flowers are in bloom. 

Red gums are well adapted to San Francisco’s climate (the largest red gum in the United States is said to be within San Francisco city limits), and they can be counted on to thrive almost everywhere in the city.  The native range of the red flowering gum is a very small area (approximately 1 square kilometer) in western Australia, southeast of Perth.

Monkey puzzle tree in the Presidio

Excited to see this monkey puzzle tree (Araucaria arcaucana) in the Presidio ≈doing well.   It's between two beautiful Queen Anne Victorians on Presidio Boulevard just west of Funston Avenue.  Monkey puzzles are native to Chile and western Argentina; they're related to other trees in the Auraucaria family, such as Norfolk Island Pine, cook pines, and bunya bunyas.  The origin of the name 'monkey puzzle' derives from its early cultivation in England around 1850, when the species was still very rare in gardens and not widely known.  Sir William Moleswort, the owner of a young specimen at Pencarrow garden near Bodmin in Cornwall, was showing it to some friends, when one of them remarked, "It would puzzle a monkey to climb that".  As the species had no popular name, first 'monkey puzzler', then 'monkey puzzle' stuck.  Very glad to see the Presidio planting interesting trees like this.  (I wish they would plant some Wollemi pines (Wollemia nobilis) (hint, hint!)).  

February Means Plum Blossoms in SF

Purple leaf plum, 59 Woodland Avenue

Plum trees (*not* cherries - they come next month!) have been blooming all over the city this past week.   My neighborhood of Parnassus Heights is famous for its plum trees - here are a couple photos from my block of the two most common varieties of plum in San Francisco.   The most common is the purple leaf plum (Prunus cerasifera), and of the many varieties of this species '‘Krauter Vesuvius’ is the one you see most in the City..   Back in the 1990s this was actually the most commonly planted tree in San Francisco, according to Friends of the Urban Forest records.   It's less common now (in part because I think the planting managers at FUF rightly think it's over-planted), but still popular, and after years of popularity, there are hundreds (thousands?) of them around the city.   The tree is gorgeous for 10 days in February, and I'm afraid that period is now just about over.   

The second, and less common, type of plum is Prunus x blireana, or Blireana plum.   The tree has double flowers that look a bit like carnations, with deeper pink than its more common relative, and the blooms last longer.   This tree is a hybrid of Prunus cerasifera 'Atropurpurea' and a double form of Prunus mume.    It was developed in France and introduced in 1906.   

Prunus X blireiana blossoms

Ginkgoes - today's the day

Ginkgoes are famous for dropping leaves all at once - often almost all of the leaves drop on a single day. I think today's the day. 

Justin Herman Plaza

Mission District Commune + Spanish Chestnuts

Kaliflowr Commune - 23rd Street

On the south side of 23rd Street between Shotwell and Folsom is a fenced-in property (a white fence stretches most of the block between Shotwell and Folsom Streets). The owner of the property is the Kaliflower commune, a group with a colorful history that has been in existence since the 1960s, and in this location since 1974. The commune tends a small orchard over the fence, with citrus and avocado trees. (You often can see avocados hanging in the trees.) The group also planted the food-producing Spanish chestnuts (Castanea sativa) and almond trees (Prunus dulcis) fronting the property.   (The chestnuts and almonds are the only examples of each that I know of on San Francisco streets.)   And as of when I walked by earlier today someone had planted an artichoke in an empty tree basin.  

As I write this in late November, the sidewalk underfoot is thick with the prickly shells of the chestnuts, which had come out earlier in the fall.  

If you'd like to take a neighborhood tour where the Kaliflowr commune and these trees are included, check out the Mission Neighborhood Tour in my book. 

Female ginkgos at peak

1044 Shrader Street

Female ginkgos are at peak fruit drop now, dropping their malodorous fruit (smells like vomit - caused by the release of butyric acid, which also gives rancid butter its horrible smell). This photo was taken on the sidewalk outside 1044 Shrader (cross street Carl), in Cole Valley.   There aren't many places in San Francisco where you can find the female of the species, which is why I created a page in Trees of San Francisco listing all of the SF locations where I knew of female ginkgos.   Particularly if you have a pre-adolescent boy in the house, now is the time to experience one of nature's most unusual and interesting smells!  

No one really knows why ginkgos adapted to have smelly fruit, but the best guess is that it was attractive to an animal, which helped the plant disperse its seeds.  You hear stories of dogs, for example, eating ginkgo seeds.  But since ginkgos have been around for hundreds of millions of years, the interesting question is, are the things that adapted to disperse it still around? Or are they extinct? 

Update:  a reader just emailed to tell me about three female ginkgos in in the courtyard of the Ping Yuen housing project at 655 Pacific (between Kearny and Grant) just inside the fence next to the sidewalk.  Great that there are some in Chinatown!   

Kauri in Jefferson Square Park

Jefferson Square Park - Queensland kauri

Found a beautiful mature Queensland kauri (Agathis robusta) in Jefferson Square Park today - near corner of Turk and Gough.    It's the only one I know of outside of Golden Gate Park, and it's bigger and more mature than any in GGP.   Cool to be still finding amazing specimens out in the open in the City!   We need more of these in San Francisco, judging by how successful this tree is.

European Tour

London Plane in Rome

I just got back from three weeks in Southern France and Italy. Two takeaways:  first, the London plane trees look so much better then in San Francisco (see photo)!  And second, we have so much more species diversity then in most European cities. I think it's because urban trees in Europe are largely planted by the municipalities.    Some bureaucrat decides that elms are the way to go, and bang - hundreds of elm trees, one after another. In the city of Nimes, France, near where we stayed, the entire city was planted with Chinese hackberries.  And in Rome, it seemed like the entire city had only three or four species.  It does create architectural unity, I guess - but I prefer our diverse tree anarchy.