I’m Gwen Outen with the VOA Special English Agriculture Report.
Farmers use different kinds of soil conservation methods toprotect their land from damage by farming and the forces of nature.One important form of soil conservation is the use of windbreaks.
Windbreaks are barriers formed by trees and other plants withmany leaves. Farmers plant them in lines around their fields.
Windbreaks stop the wind from blowing soil away. They also keepthe wind from destroying or damaging crops. They are very importantfor growing grains, such as wheat.
There have been studies done on windbreaks in parts of WestAfrica, for example. These found that grain harvests can be twentypercent higher in fields protected by windbreaks compared to fieldswithout such protection.
However, windbreaks seem to work best when they allow a littlewind to pass through. If the wall of trees and plants stops windcompletely, then violent air motions will take place close to theground. These motions cause the soil to lift up into the air whereit will be blown away.
For this reason, a windbreak is best if it has only sixty toeighty percent of the trees and plants needed to make a solid line.
An easy rule to remember is that windbreaks can protect areas upto ten times the height of the tallest trees in the windbreak.
There should be at least two lines in each windbreak. One lineshould be large trees. The second line, right next to it, can beshorter trees and other plants with leaves. Locally grown trees andplants are best for windbreaks.
Windbreaks not only protect land and crops from the wind. Theycan also provide wood products. These include wood for fuel andlonger pieces for making fences.
You can get more information about windbreaks and other forms ofsoil conservation from the group Volunteers in Technical Assistance.VITA is an organization that helps people around the world usescience and technology to solve problems. VITA is on the Web atvita.org.
You can find more Agriculture Reports at voaspecialenglish dotcom. If you have a question for us, send it to special@voanews.com.Make sure to include your name and where you live. We might be ableto answer your question on the air. But please know that we cannotanswer questions personally.
This VOA Special Agriculture Report was written by Gary Garriott.This is Gwen Outen.