Glen Schneider with wild lupin on the high ridge.
Ecological restoration is the process of assisting the recovery of an ecosystem. The Skyline Gardens Alliance has been doing just that in the high ridge volcanic area between Tilden and Sibley regional parks. This is East Bay MUD watershed land, traversed north-south by the Skyline Trail. Under special permit from EBMUD, we are doing a botanical census and restoration on 250 acres from the steam trains in Tilden to Highway 24. This area is a Noah’s Ark of native plants and is the most botanically diverse area of its size in the East Bay. We have verified 281 native species to date.
The Skyline Gardens Alliance is sponsored by the East Bay Chapter of the California Native Plant Society. Our effort is now three years old. We hold workdays twice a week (Wednesday afternoon and Sunday morning). To date, we have held more than 250 workdays totaling nearly 1,800 volunteer shifts.
Along the rocky ridge spines, we have discovered special areas that have really won our hearts. They contain spectacular, sometimes nearly intact, remnants of what must have once been. They are true meadows, containing hardly any woody plants and some of the best and most diverse populations of native grasses that I have ever seen in the East Bay: Idaho fescue, June grass, squirreltail grass, purple needlegrass, California brome, California melic, bent grass, and even pine bluegrass. They also contain a rich assortment of native perennials and bulbs: mule’s ears, checker bloom, yellow biscuit root, cobweb thistle, star lily, Ithuriel’s spear, coyote mint, soap root, and many others. These wild ones grow not just as relicts, but often in great abundance, literally by the thousands.
With such rich native ora here, our strategy is to exhaust the seed bank of the “invasives” like Italian thistle, poison hemlock, wild oats and bromes, erodium, rose clover, and many others species, mostly from Europe. Our motto is “remove the exotics.” Most of the exotics are annuals and their seeds are actually quite short-lived in the soil and quite straightforward to eradicate in a three-year time frame. That said, eradication takes tons of work, albeit glorious and fulfilling work, and requires diligence and exacting follow-up to make sure the exotics do not reseed.
One of the pioneering techniques we’re using is vinegar spray (5% acetic acid, just like you use in your kitchen) to kill young invasive seedlings. This technique is quite effective, especially on the broadleaf plants (dicots), when applied within two months of the first rains that bring up new growth. Vinegar is a “contact spray” that burns the foliage of plants, but unlike systemic weed killers like Roundup (glyphosate), it is not taken into the stems and roots. Vinegar may require follow-up sprays or hand weeding, especially on large-seeded grasses like wild oats.
As to results...the picture (top, right) is a high-ridge meadow terrace, looking southwest, after one year of mowing, spraying and hand weeding.
All plants in this early April photo are natives: besides the bloomers (blue dicks, poppies, and the yellow biscuit root), there are several species of native grasses (purple needlegrass, California melic, and June grass), soap root, golden aster, and buckwheat. Gone is the blanket of thistles, rose clover, and erodium that had covered and choked the natives growing underneath.
In the third year, once the invasive seed bank is nearly extinguished, we can then sow with a mix of locally gathered native annuals. After that, having put into place the essential elements of ecosystem recovery, our job is to keep tabs on the occasional weeds and let the natives sort themselves out.
Here’s another shot, looking east to Mount Diablo, along the Skyline trail (lower, right). Three years ago, this trail edge was a menacing thicket of Italian Thistle. Underneath were a few poppies and popcorn flowers. With the thistles gone, the natives have come roaring back. Our spirits soar as we nurture this beautiful land back to wholeness.
For more information or to volunteer, email: skylinegardens@ebcnps.org. Or, visit our website: skylinegardens.org.
Skyline Gardens’ high ridge meadow looking southwest (top photo) and east toward Mt Diablo (lower photo),
