California Native Plant Society
in collaboration with East Bay Municipal Utility District
June 7, 2018
Dear Skyliners,
Last Sunday, we cut a huge new swath of Italian thistle in the swale on the way to Barberry Peak. Because of this late spring, we were able to cut them in good time, so we can expand the project in this area. After the rains, we will spray vinegar on the thistle seedlings and we we will be well on our way. On Wednesday, we cut the resprouts on Wild Oats in the Plateau area near the Bay Grove. It's the work of the ants, and we're making steady, heartening progress.
We'll be out again on Sunday, 9:30, Siesta Gate. Please let me know if you can make it.
As the land dries out, the plants are now setting seeds. We have started collecting native seeds for our restoration plantings in the fall. In the areas we have cleared on the high ridge terraces, there is now lots of open ground where we have removed bushels of invasive annuals. Now we make plans for the native annuals to take their place.
Purple Owl's Clover (Castilleja exerta) is one of our top candidates. Let's take a closer look at them and the seeds they make.
To start off, here they are, flowering in April:
These are one of our Top Ten wildflowers. Who doesn't love them? Most of the color comes from the purple-pink bracts, which are really just bright colored leaves. The flowers themselves are the little, white "owl's faces" peeking out from the colored leaves. (Thanks to Angela for this photo.)
Time marches on. Bees come for nectar and pollinate the flowers. The land dries out, and seeds develop. Yesterday, we gathered some of these drying stalks and put them in a paper bag. We hope we got some seeds. One of the stalks looks like this:
Brown, thick, and slightly twisted, these are easy to spot on the grassy slopes, as they grow in distinctive patches. Looking closely at this mature stalk, we can see an amber-colored, beak-shaped seed capsule at the lower left. This pod has already split open and cast out its seeds. Those seeds are now lying on the ground on the south slope of Barberry Peak, starting their long summer bake.
Further up the stalk, there are greener seed capsules, where the seeds are still in formation. Here is one of those developing capsules, split open by hand, under a 20 power microscope:
Here, we can see both halves. The stem would attach at the lower right. Looking closely, we can see the seeds, each seemingly within a net-like structure. Some of them got a bit scrambled in the dissection, but in the upper half, we can see some of the seeds still lined up on the central placenta, like a row of little, nursing piglets. These seeds are still pretty green, and probably not viable.
But in the bottom of our paper bag, where we have harvested more mature seed stalks, there is a fine, brownish powder. Could those be good seeds? Let's put this under the scope and take a closer look:
Oh, my goodness .... what have we here? Look, each seed is held in a net of fine lace. What workmanship! Who would have imagined all this - worlds within worlds. And what a bounty!
Think what this means for next year.
Happy Trails,
Glen