There are two main types of herbicides, or weed killers:

Non- Selective and Selective.

Round-Up is a non-selective herbicide, killing most annual and perennial grasses, including lawn grasses, broadleaf weeds and brush. (i.e.) virtually anything that is green and growing). It is a translocated herbicide that is absorbed by the leaves and moves through the stem to the roots to kill the entire plant. Results usually takes 7 - 10 days. Repeat applications may be necessary as new seedings and vegetation emerge. Round-Up is not a soil sterilant. It has no soil activity and will not leach or run off to affect nearby vegetation.

Killex is a selective herbicide that kills most broadleaf weeds. It works by making the weed grow extremely rapidly, completing its life cycle. It can safely be sprayed onto weeds in the lawn, killing the weed, but not injuring the grass. Results take 7 days, and repeat applications may be necessary for new seedlings.

Herbicides should be applied on a warm calm day, when rain is not expected for at least six hours. Care should be taken to apply herbicides close to ground level with either a heavy spray or a dust free watering can. Mist can be picked up by a slight breeze and carried to desirable plants. For best results, weeds should also be dust free.

SOIL STERILIZERS

Soil Sterilizers kill everything growing in the soil where they are applied. They can also move in the soil, and kill trees many feet away from the place of application. They move farther and more quickly in sandy soil than in heavy clay, and move in the direction water drains. Soil sterilizers can persist in the soil for several years. Remember that tree roots can grow a considerable distance, so they can move into an area where a long-lasting herbicide is still active several years after application. Generally, it is safer to use a herbicide such as Round-Up, which is decontaminated upon contact with soil and kills only what is sprayed.