yes, they do because if they didn't the air would get poluted
It helps by prevented soil erosion and to prevent dust storms.
The answer is easy look in your science book you dork don't use the internet some of this stuff is made up and not the right answer. Now if you forgot your science book, e-mail your teacher! Or send...
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It helps from washing the soil away and helps return soil nutrients, retain moisture, and hold soil in place.
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