[Pugchief]

Originally Posted by Michael G.

My only concern with this (weed torch) is your burning the foliage and not destroying
the roots which means those weeds can grow back.

Not really true:
Weed torches are designed to heat the plants’ cells causing them to burst. This destroys the weed’s stem, which causes them to no longer be able to ingest water or nutrients, essentially killing the weeds. This is a fairly easy process that involves holding the torch and walking slowly between garden rows, killing the weeds in less than a second.

A weed ecologist from the University of California, Tom Lanine, offers information on when it is obvious that weeks have been effectively killed using this method. Essentially, he says that when the weed changes from glossy to matte, then it should die within a few hours. It is recommended to leave the weed to compost naturally and there is no need to disturb the soil.

Another expert, Mike Orzolek from Penn State, recommends that flaming weeds two to three weeks apart. Flaming will kill annual weeds completely, but does not kill the roots of perennial weeds. Often, gardeners will see new shoots a week or so after flaming and additional treatments can deplete the roots, killing the weeds.

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