Wildlife Value of Three Annual Wildflowers

by: Jeffrey Caldwell - Biologist and Horticulturist - jeffreycaldwell.blogspot.com/
photos by: Paul Furman - Bay Natives - www.baynatives.com

Gilia capitata – Globe Gilia

The butterfly at nectar at the globe gilia looks like an umber skipper (Poanes melane). The umber skipper is very adaptable as to larval hosts (a wide range of grasses, even Erharta erecta, and at least some if not many graminoids, such as Carex spissa), and so the umber skipper survives well in human-altered landscapes. In wild places it is most likely to be encountered in riparian habitats. I have been compiling lists of specific species of butterflies visiting specific native flowers. This makes 13 butterfly species for globe gilia, an excellent species for attracting butterflies, besides being beautiful and easy-to-grow -- an under-used plant for gardens! I'm pretty sure my butterfly list for Gilia capitata is not complete!

Besides being great for butterflies, Gilia capitata has enough value for bees to be recommended for bee gardens. In a 2003 study in a Berkeley bee garden, it got occasional visits by both honeybees and native bees. Native bees attracted to globe gilia included common leaf-cutters, Andrenids and very small native bees. Globe gilia is sort of a keystone species for pollinators, besides being an easy and beautiful flower for the garden.

Collinsia heterophylla - Chinese Houses

Chinese houses serves as a caterpillar plant for 3 species of butterflies (Spring Azure, Edith's Checkerspot, Variable Checkerspot). Usually no butterflies are noticed visiting the flowers. Great bee plant -- working best in large, dense patches. Patches of a square meter or less got very little pollinator attention in early garden trials. Chinese houses serve bumblebees and other bees.

Lasthenia californica – Goldfields

In a major study 40 years ago insects were collected from flowers of native plants:
Moldenke, A.R. 1971. Studies on the Species Diversity of California
Plant Communities. Ph.D. Thesis. Stanford University.

More species of flower-visiting insects, including many native bees, were found on goldfields, Lasthenia californica, than on any other native annual. So, especially in large masses -- goldfields are a good bet for supporting biodiversity.

Arthur Shapiro notes that in early spring, when little else is in flower goldfields attract "almost anything flying" in the way of butterflies. From limited specific Lepidoptera information I've listed butterflies from four families and 3 species of day-flying moths known to visit it. Goldfields are obligate "outcrossers" -- each plant must be cross-pollinated by other individual plants. For them to be effective to attract the intensity of pollinators they need it seems they need to be growing in masses. I've been told that goldfields may not reseed itself and persist unless growing in large [100 square feet, preferably more, the bigger the better] patches.

General Information on Wildflower Seeds

You shouldn't plant these if you live next to an intact natural area with the same species, in order to preserve the local genetic integrity which may be better adapted to the particular local soils and climate.

Plant them by scattering on bare ground or even on mulch sometimes will work. You might rake them in a little then pack the soil down lightly to make good contact with the soil. Keep them moist for a few weeks.

About Bay Natives – www.baynatives.com (415) 287-6755

Bay Natives, an online nursery, carries a wide selection of more than 200 varieties of Bay Area native plants plus rare and endemic selections and many choice species from across the state of California: distinctive and little-known native plants for the urban landscape.

Our growing grounds are not open to the public, and we require a minimum $50 order. We deliver to your home or job site; or you can pick up plants at our loading dock in San Francisco's Mission District. Sales only in the Bay Area, but we can ship seeds. We only carry a few types of wildflower seed, mostly live plants in pots which are not efficient to pack in boxes and ship.