Surrounded by a gravel pit, an old airport, and block after block of suburban and industrial development, 10-acre Green Cathedral doesn’t exemplify most people’s idea of wildness. On the other hand, it is a cathedral (of sorts). The former farm is one of the last remnants of green space in this part of Vancouver’s Orchards neighborhood. Our job? Ensure that the wildness Green Cathedral does contain can thrive.
That’s why Stewardship Lead Jennifer Zarnoch has been laying out test plots here to evaluate the best method to eradicate non-native shiny geranium (Geranium lucidum). Already widespread in Oregon, this invasive weed now threatens the habitats of Washington. In fact, it’s Class A weed in Washington, meaning the weed’s distribution is still limited, thus eradication is required by law.
Zarnoch’s 16 plots test for methods ranging from hand-pulling to flaming to smothering the stuff in plastic. The test plots will help us know which eradication methods will be most effective for the long-term.
She’ll also be sharing the information gathered with the Four-County Cooperative Weed Management Area, whose members (from Clark, Multnomah, Washington, and Clackamas Counties) are the regional gurus of weed eradication. They visited Green Cathedral in June; urban sites like Green Cathedral can teach us a lot about how to manage other parks and natural areas located near people, especially when information is freely shared. “It’s so important for all land managers working on weed control to share successes and challenges,” says Zarnoch. “That how we all become better at controlling weeds that outcompete our native plants.