Spring has sprung in Washington and with it comes the fulfillment of the pent up urge to go out side and garden, to become one with nature, and to do good. On Twitter this morning (@InvasiveNotes) I found this tweet: @ionxchange: 75 Plants That Attract Butterflies Mistkitscom blog http://bit.ly/aS2f1i . This inherent goodness and wholesomeness of planting flowers and encouraging pollinators especially the ostentatious, non threatening butterflies compels attention and gives form to a garden plan of action. The dream of shirking clouds of summer iridescence draws us to lists of plants that are known to attract the butterfly.
If you truly want butterflies of course you need to provide them plants that help them more than just at the end of their lives. For before there is the wonder of the shimmering display of summer garden visitors there is the caterpillar eating its way through your garden securing a resting place mostly oblivious as it hide from your brood of song birds waiting for a meal. And worse perchance if you use chemicals, the caterpillar which can reduce a favorite spring plant to a stems and stalks is easily killed by wanton chemical applications. While butterflies are feeding off nectar and are not to particular as to the source, they are usually specialists in their fuzzy not so glorious to some caterpillar stage of life. In other words caterpillars tend to be specialists feeding on only one species of plant, not necessarily the one that you would plant for summer season flowering fireworks. And sometime the plant species with which they have evolved is one you also want to eat, thereby creating a collision of desires. Do you want the parsley, fennel and dill or the Black swallowtail, Papilio polyxenes asterius Stoll?
To me then falls the Grinch’s role of pointing our gingerly that there is a collision of desires lurking within the wonderfully created list. Invasive species, garden thugs that quickly climb the garden fence and escape into natural areas upsetting the native balance and sometimes displacing most of the native diversity prized in natural settings can be dangerous beauties. (Dangerous Beauty and other Invasive Species Traps Monday, May 25, 2009) In our fascination with homogenizing the world’s landscapes, we seek garden plants that will grow from Arizona to Maine and include Alaska and Hawaii too. Armed with this list we select those plants that are known to produce nectar in quantities readily available for the more flamboyant lepidopterans. We are not choosing plants for the caterpillars and in fact our one-size-fits-all lists have been written in part show-case plants that are not greatly affected by the endless hunger of caterpillars.
So in come waltzing the invasive species: butterfly bush, (non native) honeysuckles, privet, (non native) wisteria disguised because in deed they will supply nectar to butterflies even as they do not provide a food source for the caterpillars. Because invasive species are a global issue determined locally, what is invasive in your area o=is not necessarily invasive for some one in another part of the country. Many perennials like some species of daylilies, ground covers like English ivy, and beautiful shade trees like saw-tooth oaks may be invasive in certain situations and locations. I add the oak because all oaks are great food sources for 100s of different butterfly and moth species, but not all oaks are necessarily appropriate in your garden. Be careful what you wright; gardening is both a simple pleasure and a complex philosophy filled with dangerous beauty.