Soil Sterilants

Soil sterilants containing the active ingredients prometon, diuron, bromacil, simazine, or atrazine, should never be used in residential landscapes. These herbicides move with rain or irrigation water downward or laterally in the soil, and can be taken up by roots of trees and shrubs. The result is often serious injury or death of desirable plants, even though they may be a considerable distance away from the original site of herbicide application. Sterilant herbicides remain active in the soil for years, making it possible for them to move much further than expected.
 
The photo to the right is of an Ash tree with classic symptoms of damage caused by soil sterilants. Leaves of affected plants are yellow to white between the veins while the main veins remain green. The damage resembles iron deficiency symptoms.
 
The tables below list some alternatives which can be used to control weeds where it is desirable to eliminate all vegetation. Combinations of a foliar herbicide and one or more pre-emergent herbicide work best to control existing weeds and prevent the growth of new weeds.
 
Foliar Herbicides to Control Existing Weeds
Active Ingredient Representative Brand Names
glyphosate Roundup, Killzall, Kleenup
glufosinate Finale

 

Pre-Emergent Herbicides to Prevent Weed Germination
Active Ingredient Representative Brand Names
dichlobenil Barrier, Casoron
oryzalin Surflan
pendimethalin Pendulum, Pre-M
trifluralin Preen, Treflan
 
Pre-emergent herbicides need to be incorporated into the top inch or two of soil within a few days after application. Where shallow tillage isn't practical, this can be accomplished by 1/4 inch of rainfall or sprinkler irrigation. 
 
For more information: Landscape and Garden Weed Control