Marin IJ Articles
May 6, 2017
Now that April showers have brought May flowers to your garden, it’s a good time to do a pollinator check-up.
Pollinators are the animals that buzz, fly, flit and brush through your garden picking up pollen from the male bits of a flower and dropping it onto the female bits of the same flower; that is, from the anthers to the stigmas. Pollinators help fertilize the plants so they can produce seeds and fruit.
Bees, butterflies and hummingbirds may be the most familiar pollinators, but bats, beetles, moths, a few flies and wasps, some nonbat mammals, and the occasional human with a tiny brush also carry out this important task.
How important? Within the overall ecosystem, approximately 80 to 95 percent of the plant species in natural habitats require animal-mediated pollination. As for plant foods that provide our life-support, most depend on animal-assisted pollination with wind-pollinated wheat the exception.
The Xerces Society, an international nonprofit organization that promotes invertebrate conservation, states that pollinators are necessary for the reproduction of more than two-thirds of the world’s crop species. And, not only honeybees.
A study published in Science Magazine by Lucas Garibaldi and a plethora of researchers around the world showed that, “In more than 40 important crops grown worldwide, wild pollinators improved pollination efficiency, increasing fruit set by twice that facilitated by honeybees ... pollination by managed honeybees supplemented, rather than substituted for, pollination by wild insects.”
In other words, we need these busy critters to survive.
But, wild pollinators are at risk.
According to the Pollinator Partnership (P2), which works to conserve and protect the health of vertebrate and invertebrate pollinators, “Worldwide there is disturbing evidence that pollinating animals have suffered from loss of habitat, chemical misuse, introduced and invasive plant and animal species, diseases, and parasites.”
P2 adds that many pollinators are federally “listed species,” which means it’s likely they are disappearing from natural areas. Further, the U.S. has lost more than 50 percent of its managed honeybee colonies during the past 10 years.
Indeed, the Xerces Society took its name from a blue butterfly (Glaucopsyche xerces) that was the first to become extinct in North America because of human activities. The society now states that a loss of milkweed plants (Asclepias spp.) may be contributing to a reduced number of Monarch butterflies (Danaus plexippus).
What can we do?
First, avoid using pesticides, which are largely toxic to pollinators. And, avoid buying plants treated with neonicotinoids.
Then, encourage pollinators in your garden. Like all animals, they need food, shelter and water.
• Food — Check that you have flowers with many colors, fragrances, and heights blooming throughout the growing season. And remember, butterfly larvae need to eat, too.
Because native plants and wild pollinators have co-evolved, natives are the best food source. You can find region-specific lists of native plants for pollinators on the Xerxes and P2 websites, xerxes.org and pollinator.org, a native plant app on pollinator.org, and seed sources for milkweed and other plants on xerxes.org.
In addition to native plants, herbs and some noninvasive non-natives support bees and butterflies. Be careful, though. The widely available tropical milkweed (A. curassavica), aka blood flower or scarlet milkweed, may have a negative impact on the monarchs’ health.
Lastly, butterflies, bees and beetles also eat rotten fruit, so don’t be too quick to tidy up the garden floor.
• Shelter — Plant in groups to increase efficiency and safe travels through the landscape. Canopy layers and leaf litter provide protection from weather and predators. And give native bees nesting sites: Make bee boxes and leave some soil uncovered.
• Water — Pollinators need a shallow water source to drink without drowning. And, butterflies need wet, muddy areas for moisture and minerals. But, with April’s showers and the rain this year, mud should be as easy to find as May flowers.