Tuesday, June 11, 2013

The virtues of native plants

Up close and personal with the inflorescence of a Downy Wood Mint, Blephilia ciliata. A stunning plant to be sure, and one that should be a welcome addition to any yardscape. Besides minty good looks, the plant has another thing going for it - it's native. As an indigenous North American, the mint plays host to all manner of interesting insect pollinators, and thus gives back to the environment in a way that most nonnative plants cannot.

The dates of July 26-28 will be on us before we know it, and those are important dates to note, as July's last weekend marks the 5th year of the Midwest Native Plant Conference. This event, held at the beautiful Bergamo Center in Dayton, is a great place to learn about our native plants, buy native plants, go on excellent field trips, hear interesting speakers, and generally just have a fabulous time. CLICK HERE for the complete lowdown.

A garden full of mundane Eurasian fare might look OK, but it'll mostly be operating on one dimension - aesthetics. The problem with nonnatives is that none of our insect fauna has co-evolved with foreign plants, so the interesting linkages between animal and plant are largely absent. Hence, there is no development of the food chain when a yardscape is overpopulated with nonnative plants. This stunning insect is a Dogbane Beetle, Chrysochus auratus, and it is totally wedded to dogbanes if the genus Apocynum, especially A. cannabinum. Dogbanes, which are allied to milkweeds, also attract myriad pollinators.

The close presence of your narrator and his clicking camera does not deter this Great Spangled Fritillary from sucking nectar from the T-bone steak of the flower world, Butterfly-weed, Asclepias tuberosa. The brilliant orange flowers of this native milkweed draw butterflies like a beacon, and no garden should be without it.

The treelet known as Redbud, Cercis canadensis, is a beauty year-round. The plants are festooned with drifts of pinkish-purple flowers in spring; later the interesting leaves emerge. Even in winter, the bonsai-like growth habit of the dark trunks creates beauty. But all is not aesthetics with the Redbud - scores of animals are attracted to the plant. This is the Redbud Borer, Ptosima gibbicollis, a native beetle that depends on the plant. As is the case with our native borer beetles, the linkage is harmonious - the woodboring beetles occur at low levels and don't generally harm their host, unlike introduced insects such as the notorious Emerald Ash Borer.

Finally, on to a personal favorite in the world of native shrubbery, the Ninebark, Physocarpus opulifolius. A member of the rose family, Ninebark occurs fairly commonly throughout Ohio, and is incredibly showy at all seasons. It flowers in late spring and early summer, producing plentiful corymbs of white flowers. When in bloom, especially, the plant is a surefire showstopper.

Insects are drawn to Ninebark like moths to flames, including lots of butterflies such as this Silvery Checkerspot. Photographers of insects, if they are paying attention to their surroundings, soon learn to investigate the Ninebarks when questing for interesting subjects.

Even the fruit of Ninebark is visually appealing, and the clusters of drupes hang from the plants for much of the summer. The multi-stemmed shrubs, with their shreddy exfoliating bark, look great in winter, too - sort of like a better Forsythia that actually has some value.

And who wouldn't want a beetle such as this! It is the badly named Spiraea Leaf Beetle, Calligrapha spiraea (Ninebark was once placed in the genus Spiraea), which is one of many insects that specialize on Ninebark. Look closely and you'll notice the intricately marked, colorful beetle has a hitchhiker. That's a parasitic wasp, unfortunately for the beetle, and it is injecting its eggs into the leaf beetle. Grisly as that may seem, it is part of the rich and abundant chain of life that springs up around native plants, cascading up to the level of vireos, orioles, tanagers, warblers, and other animals that we consider higher life forms. Creating valuable and infinitely interesting food webs is impossible with nonnative plants; adding natives to the mix can create diversity galore.

I hope that you can attend this year's Midwest Native Plant Conference, and learn firsthand about the world of native plants. And perhaps leave with a trunkload of valuable plants for your own yard!


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