My neighbors warned of a woody weed that would ultimately take over whatever I tried to plant there.
I tried planting annual wildflowers, but sure enough, my neighbors were right. The flowers came up beautifully only to be overtaken by a thick mass of this woody plant. The next year I sprayed the entire area with glyphosate and then tried planting the wildflower mixture again. I did the same thing the next year, but this time I sprayed the emerging weed, every time I saw it begin to grow. I even went so far as to inject each stem, as it began to emerge, with full concentrate glyphosate.
Each time the treated weed would die back, but a new plant would emerge nearby. The plant evidently spreads through a massive underground system of rhizomes and seems almost impossible to kill. Can you please identify this weed and give me some advice how I might eradicate it? -- M.A., Camillus.
Dear M.A.: The plant in the photo you sent is some kind of milkweed. It's stunted and yellow from the repeated herbicide applications, and these plants can be hard to tell apart when they aren't flowering.
There are good milkweeds and bad milkweeds. They belong to the asclepiad family. Some are native to the Northeastern United States and others were introduced here. The popular houseplants, hoyas, are tropical milkweeds. The flowers are a giveaway to the family relationship.
Native milkweeds, including butterfly milkweed, swamp milkweed and common milkweed, are the hosts for monarch butterfly caterpillars. No milkweeds, no monarchs. For that reason alone they are worth protecting. Butterfly milkweed and swamp milkweed are good garden plants. Common milkweed can be quite aggressive and could overwhelm a small, tidy garden. It would be a fine wildflower for a drainage ditch, however, with vanilla-scented pink flowers and interesting knobby seed pods.
Your experience with eradication is typical. It can take years to get rid of a persistent weed with plenty of stored energy underground. Canada thistle, horsetail, Japanese knotweed, bindweed and burdock are others of that type.
It is vital to identify a weed correctly before coming up with a strategic plan. The timing and the site are important as well. The usual formulations of glyphosate should not be used where they can get into water because the strong detergents in the mix harm aquatic life.
Swallow-worts are bad milkweeds. Pale swallow-wort is a menace in many parts of Central and Northern New York, including many state and county parks. For information on controlling swallow-wort, see sleloinvasives.org.
Carol T. Bradford, of Syracuse, has been gardening in Central New York for more than 25 years. Send questions in care of Home & Garden, The Post-Standard, P.O. Box 4915, Syracuse, NY 13221, by fax to 470-2111 or by email to email@example.com. Letters might be edited for space and clarity. »