Ideas for Getting a Firm Grip on Weed Contro

09 August 2010

Bessie Tsimba, who is originally from Zimbabwe, weeds around her onion beds in Dracut, Massachusetts

This is the VOA Special English Agriculture Report.

When is a plant considered a weed? Experts at Penn State University have a simple answer: When the undesirable qualities outweigh the good qualities.

Consider that crops generally produce several hundred seeds from each plant. By comparison, each weed plant can produce tens or even hundreds of thousands of seeds. And some buried seeds can survive up to forty years -- or even longer.

Eradicating weeds means that you have to remove all the seeds and roots so the plants will not grow back. But birds or the wind can reintroduce them to the land.

A more common way to deal with weeds is to control them enough so that the land can be used for planting. Experts advise using two or more control methods to deal with weeds.

Chemical weed killers or natural treatments like corn gluten can suppress weed growth. Dense planting of a crop can also act as a natural control.

Bill Curran at Penn State in University Park, Pennsylvania, is a professor of weed science. He says one of the most common methods for suppressing weeds is dense planting.

He says a dense, competitive crop that quickly shades the soil will help suppress many weeds. The seeds need light to grow, so blocking the sun will reduce weed growth.