VOA慢速英语2012.07.22
[audio]http://sound.yywz123.com/tingbbs/voa/voa20120722.mp3[/audio]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 is a professor of weed science at Penn State, in University Park, Pennsylvania. He says one of the most common methods for suppressing weeds is dense planting.化学除草剂或类似玉米麸等自然手段可以抑制杂草生长。作物密集种植也可以作为一种自然控制手段。宾夕法尼亚州立大学帕克分校的比尔?柯伦是一位杂草学教授。他说抑制杂草最常用的方法之一是密集种植。
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**** Hidden Message ***** He says a dense competitive crop that quickly saves the soil will help suppress many weeds. The weeds may like to grow so blacking the sun will reduce growth. ok verygood
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