There is still burning going on especially with berry fields, to control weeds. Blueberries here in Maine are 
classic, since the fields are burned even with the plants in place, to get rid of weeds. Sure beats spraying 
herbicides. So, yes, fields can be burned with the crop in place.

One great farmer's tool is a cross between a hand torch and flamethrower used to burn weeds. If you want one...

http://www.flameengineering.com/Red_Dragon_Propane_Torch_K.html

Now this post can truly be said to add to the flame wars.

Bill Truesdell
(This poster is qualified to speak on the subjects noted- worked for a commercial farmer (volunteer when his son 
was away) for five years (corn, beans, peas, strawberries, cabbage, rutabaga, and parsnips). Know many 
blueberries growers and have blueberries on my and adjoining fields. Also worked on the blueberry fields as an 
observer of the inspection of commercial pollination colonies.
Is often mistaken for Cary Grant. But, then, Cary Grant is dead so who knows what he looks like now.
Bath, Maine

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