Last Saturday was the monthly workday at my "natural home," Thatcher Woods Savanna, along the Des Plaines River. As I've mentioned before, managing a natural area is like gardening on a very large scale. And you need plenty of hands to help, especially when dealing with invasive species. One shrub we are constantly trying to contain is non-native buckthorn (Rhamnus cathartica and R. frangula and four others). Along with garlic mustard (see my post here), it is a plant I love to get rid of.
Buckthorn is a very nice, good looking shrub with dark glossy leaves, orange inner bark and berries that birds adore. It was brought to the States in the 19th century as a useful hedging material. With the help of the birds, it soon escaped and found our woods and savannas entirely to its liking. So much so that with no natural predators, it soon became the biggest bully in the woods, growing to the size of small trees and shading the ground so that native forbs couldn't get enough light. If only the deer would find it palatable! More information is available at Wisconsin DNR and Illinois DNR.
In Illinois six varieties of non-native buckthorn were declared illegal to buy or sell in 2003, including common buckthorn, glossy buckthorn, saw-toothed buckthorn, Dahurian buckthorn, Japanese buckthorn and Chinese buckthorn. Yet I have since then occasionally seen it for sale, most recently a new cultivar called "Fineline," touted as having fewer berries. No matter, it is still R. frangula, and still illegal in Illinois.
In Thatcher Woods, the Thatcher Woods Savanna Restoration Project manages buckthorn in a very direct way: we cut it down and then we burn it. Some people also cut it down and take it home to build rustic fences and trellises, for which the wood is admirably suited. When our group, headed by Victor and Jean Guarino, started twenty years ago, the woods were full of buckthorn and little else. Once the buckthorn was controlled, the native seed bank burst into germination and what had been a depauperate woods is now a fine area where flourish a number of rare and even conservative species.
This chopping and burning is a lot of work, though worthwhile. Last Saturday, our small group was augmented by some enthusiastic members of two high school ecology clubs. One group had come from Sun Prairie, Wisconsin to join students from Oak Park and River Forest High School. The two groups are planning a trip to Africa for a service project and wanted to get to know each other. What better way than working together in the woods?
Group photo courtesy Victor Guarino, Steward of Thatcher Woods. Forest Preserve volunteer information can be found at this Forest Preserve District of Cook County website.