Election Section

There are only a few fernleaf Catalina ironwood trees in public places in Berkeley. These include a couple on the west end of Ohlone Park; in Strawberry Creek Park, where the creek was daylighted, near Bonar; and a row of them against a wall on the Camellia Street side of REI’s San Pablo Avenue store. Once you’ve seen this distinctive small tree, you’ll likely start noticing more. 

Lyonothamnus floribundus subspecies asplenifolia is a California native. It’s one of many trees called “ironwood,” but isn’t related to most of them; like a lot of things, it’s in the rose family. It hails from the Channel Islands, down by Santa Barbara, and is a good example of that substrate of biology (and marvelous demonstration of how evolution happens) called “island biogeography.” That phenomenon happened a lot in California, as our mountains and deserts, climatic zones, odd mineral substrates, and geologically shifting terrain make effective biological islands on which populations get isolated to develop into species. For more on this subject, read some of the late Ernst Mayr’s work, which is accessible to read and not hard to find. 

In its home habitat fernleaf ironwood doesn’t make many seedlings, though its tine seeds are easily enough dispersed by wind. It reproduces by sprouting new trees from underground runners. This makes for dense single-species groves without much understory. I’ve never heard of a cultivated Catalina ironwood throwing sprouts from runners, though. That’s more a concern with things like wisteria, which can slowly take over a yard under the right conditions without some attention. 

Aside from the handsome notched leaves, fernleaf ironwood can be distinguished by its flat panicles of little white flowers and its narrowly shredding bark, which starts out brown and weathers to gray. On the islands, that bark serves one odd purpose: island scrub-jays, larger and a bit brighter than our closely related local scrub-jay species, use the spaces behind the shreds to cache their food, often alligator lizards. Apparently scrub-jays, like shrikes, appreciate lizard jerky. 

The other living Lyonothamnus subspecies, L.f. ssp. floribundus, appears, despite its name, to be derived from the fernleaf sorts of ironwood and its simple, long leaves often have a notch or two at the base, a sort of vestigial trace of its ancestry. The fossil record shows Lyonothamnis species with very similar ferny leaves in places as scattered as northern Oregon, Nevada, southern California, and a simpler-leafed sort right near us, in Moraga. In general, the plain floribundus types have been found in more coastal locations, and the fernleaf types in the interior. Pliocene fossils of the asplenifolius sort have been found in Death Valley.  

(Joe, that guy who writes about Berkeley wildlife on opposite Tuesdays, and I just got back from a quick trip to Death Valley. I have urgent advice: Drop everything and go. Make motel reservations first, in Beatty Nevada or Ridgecrest California; lodging is tight this year, but the park itself absorbs its masses easily. It’s even better than you’ve heard. Drive in, get out of the car, stand still, look carefully, and inhale. The scents of the desert flowers are as symphonically gorgeous as the geologic, meteorologic, and biologic vistas.)  

This ironwood’s journey to our area is a homecoming of sorts. The species—any variation of it—no longer occurs naturally on the mainland. But in 1894, a botanist named Francesco Franceschi, brought some seeds and a live tree back from Santa Cruz Island. He and his two sons were sailing back to Santa Barbara with their precious cargo when their little boat was beset by high winds, rough seas, and suspicious coast guards, who thought the little family group were outlaws—smugglers, I suppose.  

The guards fired shots at the vessel, which was being swamped already, and it began to sink. Dr. Franceschi navigated while his sons bailed water, and all survived to reach harbor safely. The imperiled tree flourished in Franceschi’s nursery, and within three years in produced enough stock to be introduced to the nursery trade.  

I’d like to see more of this tree in Berkeley. If it’s tough enough to ride out the ages and survive attack by proto-Homeland Security agents, let it encourage us all.  

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