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.

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.