Tackling superweeds

If anyone studying the new "superweeds" that have developed resistance to Roundup wants new territory, they're welcome to come to my yard. I've been trying to reduce the lawn and add garden space to reduce mowing, which pollutes the air, but bishop's weed keeps taking over.

I don't know if it was ever susceptible to Roundup to begin with, but it sure isn't now.

U.S. farmers are facing increasing problems with superweeds, according to a story in yesterday's New York Times. Ten weed species in 22 states are resistant to Roundup -- also generically referred to as glyphosate. But that was the whole point of the genetically-engineered seeds farmers have been using. They can spray a field with Roundup to kill the weeds, but not harm the corn or soybeans.

Now, however, they're having to use more harmful herbicides to get rid of the weeds. And one farmer the Times profiled has gone back to plowing instead of the no-till farming method, which reduces runoff.

Today, the Agricultural Research Service announced it has come up with a potentially better strategy -- using herbicides to sterilize weeds instead of killing them outright.

The ARS says that exotic annual grasses such as Japanese brome, cheatgrass and medusahead are harming millions of acres of grassland in the western United States. But when herbicides are used to control the grasses, sometimes the desirable perennial grasses are harmed, too.

However, the "growth regulator" herbicides don't "greatly" harm desirable perennial grasses but reduce the seed production of the annual weeds. Since annual grass seeds only survive in soil a year or two, it should only take one to three years of herbicide treatment at the right growth stage to greatly reduce the soil seed bank of annual weedy grasses without harming perennial grasses, the researchers concluded.

Wonder if they have something similar I could use on the bishop's weed.