Recently, after hearing the words “keystone plant,” I had to take pause. As a longtime gardener, voracious garden book reader, not to mention a gardening author, I was surprised that I didn’t know what this term meant.
What exactly is a keystone plant?
Photograph by Britt Willoughby Dyer, from Gardening 101: Aster.
Asters are host plants to more than a hundred different species of caterpillars.
As you might imagine, a keystone plant plays a huge part and has a massive effect on the diversity, abundance, and survival of other species, like insects and birds, in an ecosystem.
Aspens are critical to the boreal forest and its ecosystem.
What are examples of keystone plants?
Photograph by Bo Insogna via Flickr.
The saguaro cactus, native to the Sonoran Desert of the southwest United States and northwestern Mexico, is one keystone species. In the boreal forest, trees such as willows and aspens are critical habitats for birds, insects, fungi, and lichens.
Native milkweed is the only food that monarchs will eat and is their only host plant, making it critical for the survival of this iconic butterfly.
Photograph by Alan Levine via Flickr.
Saguaro cacti provide shelter and food to birds.
Why should you care?
The world’s plant and animal diversity is dwindling at alarming rates. Keystone plants are critical to stemming the loss.