By Kathleen Reynolds
Let’s talk about the birds and bees. No, not that talk. This is about pollinators; those helpful creatures that flit from flower to flower, spreading pollen.
Over 80 percent of flowering plants need pollinators. Many birds and insects provide this important benefit. Hummingbirds, bees, butterflies, even bats can help support our biodiversity with their pollination. They pollinate flowering plants that produce fruits, vegetables, and nuts. Over 1200 types of crops require pollination.
The California Department of Fish and Wildlife (CDFW) says in their Importance of Pollinators information, “One of the benefits of native pollinators is that they are adapted to local ecosystems, so making use of their pollination services may reduce the need for management and maintenance.”
CDFW also states, “Evidence points to a general reduction in pollinator diversity and abundance…In North America, some hummingbird, butterfly, and bat species are in decline. One quarter of all bumble bee species are threatened. In the west, a review found an average annual decline of 1.6% across common and rare butterfly species. Some have experienced catastrophic declines, such as the western population of monarch butterflies, which has experienced a 99% reduction since the 1980s.”
Habitat loss is one of the major threats to pollinators. Pesticide use, disease, parasites, and non-native species also pose risks to pollinators. Climate change can amplify the effects of these stressors on pollinators, including potentially shifting the ranges of plant species and the timing of flowering.
As the climate changed over thousands of years, native plants adapted and so did the insects. Then people got away from using natives in favor of cultivated plants. Growing populations and expanding cities have also threatened crucial pollinators and native plants.
“As we’ve changed our habitats, the destruction has been heavy on insects,” says environmental journalist and photographer George Oxford Miller, a prolific writer of native plant guidebooks and articles. “Herbicides have affected insects such as butterflies and, particularly, bees. Bees are most important because of the plants they pollinate for human consumption.”
“We need to employ holistic practices to create a habitat that’s a garden oasis in our yards. To keep their population sustainable, they must have habitat to replace what was destroyed by development. They need food, water, shelter and nesting opportunities. This can be accomplished even in limited size if done according to their needs.”
Miller and other experts agree that the home gardener should choose plants that are colorful all the seasons of a year.
“I’ve done it in my small yard for 15 years with plantings and a bee hotel,” says Miller. “Understand what butterflies need to reproduce and provide it.”
“The most prolific time for hummingbirds and many other species is early spring into late fall. They establish a habitat to sustain the local population. Some bees travel no farther than 30 to 40 yards; honeybees have a much larger range.”
His predictions are dire. “There’s an insect apocalypse with populations diminishing at such (fast) rates. Having neighborhood backyard havens increases the ratio. People got away from using native plants but now there’s a high percentage of landscapes using natives. Nurseries can readily supply native plants for most people’s yards.”
If you’re not ready for your own bee hotel, butterfly sanctuaries may be a good alternative.
Did you know that Napa County alone has over 50 types of butterflies? The monarch’s wingspan can be up to 4 inches, making it one of the largest along with the Mourning Clock and Swallowtail varieties. The blue hairstreak, having a one-half inch wingspan, is the smallest.
In the article “Planting Natives Brings Butterflies, and other Pollinators,” Napa County Master Gardener Cindy Watter writes, “Many California native plants are irresistible to butterflies, and most natives need little water to thrive. The California wild lilac (Ceanothus) can be a shrub or ground cover, with blooms in an assortment of colors...They need almost no water in summer.”
She also names butterfly bush (Buddleia), flannel bush (Fremontodendron), California marigold (Tagetes lemonii), mock orange (Philadelphus lewisii) and the Matilija poppy (Romneya coulteri) as good attractors. Another is the common buckeye, plentiful in Napa County
You can see most of these plants in Napa at Skyline Park in the Martha Walker Native Habitat Garden, maintained by the Napa Valley Chapter of the California Native Plant Society (napavalleycnps.org). The Society usually has a twice-yearly native plant sale in the fall and spring.
In the paper “Gardening for Butterflies” on the Napa County Master Gardeners website (napamg.ucanr.edu), writers Dean Donaldson, Farm Advisor; V. Fish and P. Pawl, UCCE Master Gardeners, advise the best ways to attract butterflies.
“Home gardeners can encourage butterflies by providing blooming flowers, resting places and garden damp spots,” says the article. “Butterflies need water, food and shelter to survive, but each type prefers a different food source so they don’t compete with each other…While some butterfly species are attracted to specific types of plants, most are general feeders. Butterflies are attracted to flowers planted as a group; avoid planting flowers in lines or mixtures.”
They point out that, because butterflies can’t drink from open water, a good option is to give them a pan of wet sand in an open area under a dripping faucet. They like to rest on large rocks and inside of trees, shaded and protected.
The CDFW says that practicing integrated pest management can protect pollinator health through ecosystem management that does not rely solely on pesticides.
Creating a pollinator backyard garden using native plants and eliminating home use of herbicides and pesticides can help repair some of the damage done to our local ecosystems and sustain the pollinators we need so much.
For more information about native plants and pollinators, George Oxford Miller’s book “Native Plant Gardening, Birds, Bees and Butterflies” is available at Napa Bookmine.