The California buckeye (Aesculus californica) at 2694 McAllister is one of San Francisco’s most notable trees, and it’s certainly the most famous of the trees that are native to San Francisco. It’s a huge specimen, and very old - so old that many think it existed before the turn of the century neighborhood around it. It’s in full bloom right now, with hundreds of the showy clusters of white flowers that the tree puts out in May and June every year. When I’m asked about my favorite trees in the City, this one is always at or near the top.

This tree has an interesting recent history. In 1999 the then-owner of the property posted plans to build a second home on the corner lot. The designs for the house placed it in a spot that would have required the removal of the tree. The City’s tree-lovers, led by environmentalist activist Beatrice Laws, responded with such a fierce outcry - hundreds of citizens signed petitions and letters to City Hall - that the property owner ultimately conceded. The plans were redrawn to move the home to a part of the lot where it would not damage the tree, and as part of the settlement, an easement was drawn up between the property owner and Friends of the Urban Forest (my law firm at the time wrote the easement as pro bono project for FUF) to permanently protect the tree. Under the easement, any removal or significant pruning to the tree requires FUF’s consent. At the time, it was the only street tree in the City protected by an easement (I’m told there is now a second).

Much later, in 2019, the tree was granted “landmark tree” status by the San Francisco Urban Forestry Council in a unanimous vote, granting it a second layer of protection.

California buckeyes can be found on wind-protected sites in the dry slopes and canyons of California’s coastal range and Sierra foothills. The leaves of the tree typically drop in July (an adaptation to our long, dry summers) unless summer water is provided. After the tree’s flowers fade, one or two pear-shaped fruits form on each flower cluster, and inside each fruit’s leathery jacket is a seed with a shiny brown coat. California’s native Americans knew the tree - they crushed the tree’s poisonous seeds and added them to dammed-up streams to stupefy fish, making them easy to catch. (Even today, you can find California buckeyes near old Indian campgrounds.)