“Nature’s Best Hope” is about a cure for the pox the country has instigated on the environment, which has seen 95% of the country logged, tilled, drained, grazed, paved or otherwise developed. The earth has limited resources, says professor of entomology and wildlife ecology Douglas Tallamy, and the more we take for our own uses, the less there is for other species.
“The problem, of course, is that it’s the species that comprise nature that keep us alive. I mean, we’ve lost 3 billion birds in the last 50 years — that’s a third of our American bird population.” The decline of global insects is equally severe. More than 40% of insect species are declining, and a third are endangered. “Insects are the little things that run the world. If we lose them, we’re gone, period.”
But back to the cure. Sure, the country has parks and preserves, but they’re too small and isolated to sustain the species that run our ecosystems. Habitat fragmentation is a huge problem. The solution, says Tallamy, is to set up functional ecosystems on private property and everywhere there’re people. “Of course, all the other living things need ecosystem services, too. There’s no place on the planet where it’s safe to have failed ecosystems. That’s why we can’t just focus on parks and preserves.”
Tallamy names this massive restorative cure the Homegrown National Park. It will be the biggest park in the country, with an estimated 20 million acres of conservation corridors. The biggest ask will be to convince people to reduce the area of their lawns: No mean task for something considered a status symbol, but it can be done. He tells the story of a woman whose staunch lawn-loving father was convinced to reduce it when she told him milkweeds could help save the monarch butterfly.
The man was “an extreme of ‘keeping up with the Jones’ model,” says Tallamy. “His lawn had to be better than everyone else’s. It was lawn. There were no other plants, and the greener it was, the better he felt.” The woman had asked her father to watch her children while she was involved in the monarch project and was gone a lot. Finally, he asked her what she was doing and when she told him, he asked if he could plant milkweeds, too.
“Then he sat there and watched the monarchs come and lay their eggs,” says Tallamy. “He watched the caterpillars hatch and watched them develop, and that’s all it took. All of a sudden, he said, ‘I need more milkweeds. I don’t have enough for the larvae.’”
Native plants are critical to sustain species and support local ecosystems. In the case of monarchs, the endangered butterflies evolved to handle the milkweeds’ toxicity. “They’re locked into what they co-evolved with, which is why our insects are so terrible at eating plants from China or anyplace else,” says Tallamy, “They’ve not been exposed over evolutionary time to these plants long enough to develop the adaptations to be able to eat them.”
Most vertebrates don’t eat plants directly, he explains, but they eat something that does, typically insects. Chickadees in your yard need six to nine thousand caterpillars to produce one clutch. To support the caterpillars, you need native plants, which are the foundation of local food webs, giving butterflies, birds and other wildlife what they need to survive.
To help people find native plants, Tallamy’s assistant, Kimberly Shropshire, created the Native Plants Finder, at
https://nwf.org/nativeplantfinder, with help from the US Forest Service. Some plants native to the Northwest are sunflowers, golden rod, lupine, Indian paintbrush and yarrow. Native trees include a wide variety of fruit trees (such as cherry, beach plum and apple), as well as willow, birch, aspen and cottonwood, among others.
Shropshire made a valuable discovery over decades of working with Tallamy. Just a few plant genera, or class of species, provide sustenance for most butterflies and moths critical to food webs. Some genera, such as oak, cherry and willow, host hundreds of caterpillar species, while others are home to far less. Tallamy calls these hyperproductive plants “keystones” because they have a disproportionately large effect on the abundance and diversity of other species in an ecosystem — like the wildlife he’s trying to sustain. Without a minimal number of keystone plants, according to Tallamy, the food web “all but falls apart.”
When the Endangered Species Act was written in 1973 to save individual species, says Tallamy, we weren’t thinking of nature as a unit made up of interactive parts. “Nature is like a watch. You can’t take one part out and expect the watch to work really well, because all those parts interact with each other.”
What is happening now is considered by experts in the field to be the world’s sixth mass extinction. More than 500 species are at risk and likely to be lost within 20 years. It’s why Tallamy feels an urgency to recruit more people willing to stem the tide in their own yards and communities. And it’s one of the reasons he came up with the idea of Homegrown National Park.
“Everyone requires healthy ecosystems. It’s not a political thing. Everybody needs it, and the quality of your life depends on the quality of local ecosystems. If you own a piece of earth — we call it private property — you have the obligation of being a good steward of that place. If you don’t want to do that, sell it to someone who does, because that’s part of the obligation of living on planet Earth.”
On the Homegrown National Park website, an image of a bumblebee sits atop Tallamy’s message: “In the past, we’ve asked one thing of our gardens: that they be pretty. Now they have to support life, sequester carbon, feed pollinators and manage water.”
Tallamy doesn’t believe this goal is too much to ask because we don’t have any other choice. “More and more people realize we have a serious issue here. It’s a global crisis with a grassroots solution,” says Tallamy. “We don’t have to depend on gridlock government or any president. We can do this ourselves.”
Read more in the Apr. 7-13, 2021 issue.