The best weed control is a healthy, well managed lawn. The premise for this statement is that a healthy dense turf canopy provides a competitive edge over weeds.Weeds are opportunist and germinate and grow where the turf becomes sparse.
Generally the reason a lawn's turf canopy becomes sparse is because of other turf management problems. Often the type of weeds present can be used to help identify these problems. Goose grass and path rush are two common weeds that are found where soils have become heavily compacted. Sedges and kyllinga normally are found on poorly drained areas and algae is often associated with excessive surface water.
For most turf species soil pH levels need to be only slightly acid. but when the pH becomes too low for healthy turf oxalis (woodsorrel) may encroach and the plantains generally appear on higher pH soils. Legumes such as clover and lespedeza can be indicators of low nitrogen fertility.
Next time your lawn becomes infested with weeds take note of the type of weeds and maybe the remedy will be some alterations in cultural practices with less dependency on herbicides.
Published July 10, 2006
Dr. Wayne Wells is an Extension Professor and Turfgrass Specialist. His mailing address is Department of Plant and Soil Sciences, Mail Stop 9555, Mississippi State, MS 39762. wwells@ext.msstate.edu