Echoes of Leopold: The Spread of Invasive Species

Thus the English Sparrow, rendered innocuous by the shrinkage in horse was succeeded by the starling, who thrives in the wake of tractors. The chestnut blight, which had no passport beyond the west boundary of chestnuts, is being followed by Dutch elm disease, with every chance of spreading to the west boundary of elms. The white pine blister rust, stopped in its westward march by the treeless plains effected a new landing via the back door, and is now romping down the Rocking from Idaho toward California. Ecological stowaways began to arrive with the earliest settlements...-Aldo Leopold (Sketches Here and There)

What's remarkable about this statement is that it was true 1949 and remains true today. If nothing else the purchase and use of cheap bird seed with millet and cracked corn have benefited the House Sparrow and the Starling. Leopold missed the Japanese Beetle introduced to the U.S. in 1916, and he wasn't here to see the introduction of the Emerald Ash Borer or the European Oak Borer. Native plants are under constant attack which can be likened to the spread to the European diseases amongst Pre-Columbian native peoples in the New World. Trees and plants native to the Americas have no or little defenses from these invaders, and we risk losing them because of our landscaping and agricultural behaviors.

Leopold wondered in the 1940's if the West would get a handle on managing Cheat Grass. This also seems to be a battle lost by native plants. The question remains whether or not we have learned anything in 6 plus decades.

Leopold dedicated a good portion of his life to reclaiming the landscape for native plants. He worked on the Curtis Prairie restoration and his famous farm alongside the Wisconsin River. This challenge us to reclaim landscape for native plants is passed down to us and has new standard bearers. Each time we make a decision about which plants put in our yards, which ones to remove, we are having the same effect. Leopold described it as having the same powers as God, the ability to create (via shovel) and the ability to take away or destroy (via axe).

Douglas Tallamy is one of these standard bearers. The author of Brining Nature Home challenges to landscape native plants to the benefit of native insects, birds, and other wildlife. It was in reading Bringing Nature Home that I first felt a moral or ethical obligation to give back my land, to make my yard a viable habitat. If you aren't sure where to start take a look at Bring Nature Home or The Living Landscape, and then also check out the National Wildlife Federation's Gardening for Wildlife program for ideas.