Those battling weeds in natural areas can’t help being depressed as they drive along and see large populations of enemy plants. Late summer is especially bad as these weeds start setting seed.
Some of these weeds are biennials, and can be controlled if they are mowed at the right time. Over the last few years the mowing crews seem to have realized this and now are trying to work at the right time. Unfortunately, with the large mowers they use they can’t get next to sign posts, guard rails, and other permanent structures at the edge of the highways.
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| Road crews are unable to mow next to guard rails and other permanent structures in the right-of-way |
Kathie and I did a brief survey of the unmowed weeds present along this particular Dane County Highway KP guard rail. The diversity was not surprising. What was disturbing was the number of perennial species, since these cannot be controlled by mowing. They must be sprayed with a broad-leaf-active herbicide.
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Weed along guard rail
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Life style
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Aspen
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Perennial
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Bird’s foot trefoil
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Perennial
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Canada thistle
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Perennial
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Chicory
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Perennial
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Common ragweed
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Annual
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Giant ragweed
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Annual
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Queen Anne’s lace
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Biennial
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Trifolium (short white
clover) |
Perennial
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White sweet clover
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Biennial
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Wild parsnip
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Biennial
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Yellow sweet clover
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Biennial
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