"Will some plants still resprout?"
Some perennial plants with long taproots (such as dandelion) may resprout from the lower root area if it has not been scalded. In a lawn you can remove the top growth and dig a hole above the root....manually remove some of the root if possible. Pour the kettle water into the hole and it will seep down and kill whatever sections of the weed root it can reach. Refill the hole with soil and sow some grass seed right away so there is no bare spot where airborne weed seeds can take hold.
If a weed resprouts in a sidewalk crack or driveway repeat the boiling water treatment. Each time the weed resprouts the growth will be smaller and weaker and the most stubborn perennial weeds will eventually die, usually after two or three treatments.
"Does the boiling water also kill the biota in the soil?"
Boiling water will kill whatever biota it touches, however, because the stream of kettle water is carefully and slowly poured onto a small area this effect is reduced. New biota will quickly return to the area within a few days.
"What precautions should I take when using boiling water to kill weeds?"
*Use a pot holder or hotmitt to hold the kettle handle to prevent burning your hand from the kettle's heat.
*Pour the kettle water slowly and from a close height of a few inches above the plant crown to avoid splashing.
*Wear long pants and closed-toe shoes. Shorts and sandals can't protect your skin if you accidentally splash the kettle water.
Trudi
Entered by Trudi_d