Home & Garden

Green Neighbors: Alder News That’s Fit to Print

By Ron Sullivan
Thursday May 08, 2008 - 10:55:00 AM
Alder trunk and rhomboid leaves in Sunol Regional Park.
Ron Sullivan
Alder trunk and rhomboid leaves in Sunol Regional Park.

If you’re like Joe and me, you’re spending as much of this sunny weather as you can outdoors, especially in our handy local parks. The breeding birds are here, and they’re putting on a show as they sing and chase and carry on, establishing territories, picking mates, building nests. The bloom season is at its height, multiple species carpeting outer Point Reyes and interior grassy hillsides.  

These places get a bit hot in full sun, if like me you’re an old goat dragging herself uphill against gravity, which I swear is increasing lately about as fast as gas prices. I’m hauling too much mass with too little oxygen, granted, but could it be that what’s replacing the time that’s obviously leaking out of the universe is an insidious backwash of gravity?  

So: Hot, sweaty, wondering if my sunscreen is good enough to prevent getting a few more divots at the dermatologist’s, what would I want to see?  

A nice lush line of alders. Somewhere within that line there will be a creek, and cool shade under them. Maybe there’ll even be a handy overhanging root I can sit on and dangle my feet in the water. 

Alders are in the same family as birches, and they mostly have similar preferences: in these parts, plenty of water year-round is a significant one. They’re one of the trees (like willows and sycamores) that mark watercourses, and as the grasses turn lion-gold and then camel-brown, you can spot their green banners from a great distance.  

Our local representative is white or California alder, Alnus rhombifolia. The leaves are indeed pretty rhombus-shaped, and they flutter engagingly with a subtle faint rustle in the slight breeze that a running creek produces. To a hiker, that’s Mother Nature’s Welcome sign and it beats HoJo’s orange roof by a long dry mile. 

This might explain why Donald Culross Peattie, in the short description of the species in his classic A Natural History of Western Trees, breaks into poetry a few times. 


In the brief period of cold weather in California the leaves of this Alder drop from the trees, and it is then, in January, that the catkins bloom on the naked twigs. To look down then from some mountain-side on the green-gold of the Alders all in bloom for miles up and down the creek is one of the loveliest floral sights of the year in the California Coast Ranges … Yet flowers these catkins are, of course-male flowers which, being wind-pollinated, have of necessity immense amounts of buoyant pollen to loose upon the chill airs. A slight tap on a flowering twig will send a whole nebula of fertility to floating in the air, a golden haze that slowly drifts away, only by chance to find the little female flowers so neatly packed in small cone-like clusters. 


Alder isn’t a major timber source, but it does grow straight and tall enough to make decent boards and furniture. You’d have to be a homesteading handcrafter to work on that scale, I’d think. It’s also good firewood, on a similar scale. It does re-grow pretty quickly. 

The local indigenes used it for that, specifically for tinder and for the drill part of a fire-building kit. They used the supple roots in basketry and made a skin-soothing wash by boiling the bark. Considering that aspirin is a refinement of an ingredient found in willow bark (salicylic acid, of course: salix = willow) that cool streamside is looking better and better: drugstore as well as rest stop.  

Alder roots, like other tree roots, were harvested for basketry in a selective, rotational manner, taking a few from a tree or grove and then leaving the producers alone for some years to recover. Smart move, in recognizing not only that a renewable resource needs appropriate time to renew itself but also that the service of live, standing alders in sheltering wildlife (along with humans) and maintaining streambanks is invaluable.  

Creekside vegetation and its inhabitants are among the most devastated of ecosystems in California. Bird species like the least Bell’s vireo and yellow-billed cuckoo have become vanishingly rare. This destruction has effects that reach far downstream and all the way into our own daily lives: our diets, for example.  

Siltation caused by erosion of streambanks-in turn a product of destruction of streamside and forest vegetation that holds the soil in place and filters hard rains-as well as the heating of now shallow and unshaded waters, kill off salmon eggs and young salmon. It seems clear that this is at least as bad as overfishing, and certainly harder to fix.  

One wonders if the people who have, unthinkingly or greedily or both, perpetuated the sloppy way we use our resources have ever sat under a cluster of alders, feet in the creek, and considered their ways.