Gray hairstreak buttefly on encelia

By Rebecca K. O’Connor

On Feb. 7, The Xerces Society announced a precipitous decline in the annual census of monarch numbers at overwintering sites in central Mexico.

Last year, eastern monarchs were found in 2.2 hectares and this year they inhabited only 0.9 hectares. This report followed another on western monarchs in January that showed a slight decline in a population that still sits at only 5% of population numbers recorded in the 1980s.

I found this disheartening even though I know it was a difficult weather year for the monarchs on the West Coast. Yet, I know that I contributed at least 30 monarchs to the population this year with the small patch of narrowleaf milkweed in my front yard. I also read on social media about friends who had many more monarchs in their established milkweed gardens. It makes me want to double-down on adding native plants to my garden not just for the monarch, but for all our local butterflies.

Native plants and the caterpillars that depend on them are the foundation of our local ecosystems. I’ve read that 96% of all terrestrial bird species feed insects to their young and caterpillars are an important part of this food source. Yet, many caterpillars depend on a small selection of native plant species as their host plants. If a butterfly species cannot readily find the native plants for their larvae to consume, that species disappears along with all the animal life that depends on them.

Surely the work the Rivers & Lands Conservancy does to conserve natural and wild open spaces as well as planting California native gardens has a tremendous impact on supporting these species. Yet, I wonder how exponential that impact could be if we all just planted a few California natives in our own gardens.

Planting a selection of flowering plants along with host plants for caterpillars can dramatically increase the number of butterflies as well as insectivorous bird species in your yard. West coast lady butterfly larvae are exclusive to mallows like the desert globemallow. Wild lilac of the Ceonothus species, a vibrant blue blossom shrub hosts pale swallowtails and the stunning ceonothus silk moth. California buckwheat feeds Behr’s metal mark and deerweed, the yellow-flowering shrubs we often see accompanying buckwheat in local habitats, host the delicate marine blue butterfly. Even trees such as native coast live oaks host a variety of species like California hairstreaks and California sisters.

A variety of native wildflowers, flowering shrubs and even some of the non-native flowering plants in our gardens can provide the nectar needed for adult butterflies. Add in some rocks in open areas where cold-blooded butterflies can sun themselves and they have everything they need to thrive.

If you are looking for resources for California native host and flowering plants that will thrive in our region, visit California Native Plant Society’s Calscape website and click on the “butterflies” tab. There you can input your address and find local butterflies and the host plants suitable for your area.

You can also join Rivers & Lands Conservancy to volunteer at one of our California native garden community events. On Saturday, March 23, we will be working with the city of Riverside parks for a California native planting at the base of Mount Rubidoux. Check our website in the coming weeks for more information and to sign up. Volunteering is a great way to learn more about the plants that thrive in the Inland Empire and get some ideas for your own garden. It is also a wonderful way to support local pollinators and birds.

It was only a year ago that I planted native narrowleaf milkweed in my yard and I’ve since added desert globemallow, bush sunflower, native flowering grasses, yarrow and sage species. I’ve seen painted ladies, tiger swallowtails and gray hairstreaks as well as the monarchs I set out to attract. In my opinion, it isn’t much of a garden yet, but the butterflies seem to disagree. I suspect as well, that when the hooded orioles return this summer, they are also going to enjoy my efforts. I don’t mind sharing a few of my homegrown caterpillars, especially with such beautiful company.

Rebecca K. O’Connor is the co-executive director of Rivers & Lands Conservancy, a California Arts Council individual artist fellow and the author of several books on the natural world.