If you’ve decided to garden with native plants to attract more birds, butterflies, and bees to your yard or to help save wildlife, great! For added success, focus on keystone plant species.
What’s a keystone?
It’s the center stone in an arch that supports all of the other stones. Without it, the whole arch crumbles. The same is true in nature.
Keystone plants have an equally outsized effect, influencing both the diversity and abundance of species within their ecosystems. Why? Because plants produce the energy that animals need to survive. Without them, our food web would crumble.
To have a healthy world with many wildlife species, we need that plant energy to spread out far and wide through the food web. Herbivores are the first link in this energy transfer. They convert plant energy into a form other animals can use.
And this is where it gets weird for some people, because the most important players in this energy-transfer story are insects – specifically, the caterpillars of butterflies and moths.
Yup, those squishy, wriggly critters transfer more plant energy to other animals than any other herbivore group.
Nearly 96% of our backyard birds in the Northeast rely on caterpillars to feed their young. Even birds that come to your feeder need caterpillars–and a lot of them. A chickadee needs between 6000-9000 caterpillars to raise one clutch of nestlings.
So how do we ensure there are enough caterpillars to feed wildlife? We turn to the powerhouses.
Just 5% of native plants—the keystone plants—support 75% of the needed caterpillar species that contribute the most energy to the food web.
If you’ve grown vegetables, we understand that it may seem crazy to purposefully attract caterpillars. Don’t worry: native plants attract native butterflies and moths, whose caterpillars will attract more birds, who along with other critters will eat most of the caterpillars. Those that aren’t eaten will become the pollinators that we want to visit our gardens. That’s the whole point. In fact, your vegetable garden will thrive if you attract more pollinators.
Willing to give it a try? Great! Want to go for the gold star?
We use keystone plants to support the insects who feed wildlife. For a healthy and sustainable habitat, we also need to support the insects who help the plants thrive – the pollinators. We can’t forget to show some love to the bees!
To save wildlife, and nature in general, garden for caterpillars and bees.
You probably already know that bees are some of the most important pollinators of plants. Many people are worried about honeybees, but they’re not the most important, or abundant, pollinators of our native plants.
That’s why we focus on two types of keystone plants:
- “host plants” that feed caterpillars
- and those that feed specialist bees who only eat pollen from specific plants.
Why focus on specialist bees? Because these picky eaters require a specific plant to survive, they are among our most endangered pollinators. If their favored plant disappears, they can’t switch to a different one. However, other bees and pollinators who aren’t picky eaters can also thrive on the plants the specialist bees must have to survive.
Luckily, the top 14% of keystone plants support 90% of native caterpillars and 60% of specialist bees. Like we said, they are powerhouses. We all should be adding them to our landscapes.
More and more Americans are doing just that. A 2021 gardening survey by the National Gardening Association found that 67.2 million American households purchased plants to help butterflies, bees, and birds, and nearly 44 million of them bought at least one native plant. Olmsted City is committed to using them almost exclusively.
Please join us! Download a list of keystone plants for our region from the National Wildlife Federation (link below). See you at the park!
From left to right: White Wood Aster, Black Eyed Susan, and Goldenrod
Where did we get our facts?
All of this information is explained for general audiences by Dr. Doug Tallamy, the scientist involved in most of this research, in this video, “Native Keystone Plants for Wildlife”: https://www.youtube.com/watch?v=O5cXccWx030
The results of the 2021 National Gardening Survey conducted by the National Gardening Association were discussed by Mary Phillips, head of the National Wildlife Federation’s Garden for Wildlife program, in this same video link above. The survey is available here: https://garden.org/store/view/9/National-Gardening-Survey-2021-Edition/.
To review the scientific data, please see: Narango, D.L., Tallamy, D.W, & Shropshire, K.J. Few keystone plant genera support the majority of Lepidoptera species. Nat Commun 11, 5751 (2020). https://doi.org/10.1038/s41467-020-19565-4.
Learn more and get started:
- Keystone Plants for Ecoregion 8: https://www.nwf.org/
- Mohawk Valley Chapter of the Wild Ones, a national organization that promotes environmentally sound landscaping practices to preserve biodiversity through the preservation, restoration and establishment of native plant communities: https://mohawkvalley.wildones.org/
- Homegrown National Park: a grassroots conservation project to restore habitat where we live and work, to regenerate biodiversity and ecosystem function
https://homegrownnationalpark.org/
Contributors: Jill Shultz
