Question
Once I get rid of the tall fescue in my yard how do I keep it from coming back?

Answer
Think prevention, pre-emergent and cultural operations. Prevention is quite difficult because the tall fescue grows from seed which can be brought on to the lawn in many ways. Application of pre-emergent chemicals will prevent all seeds from germinating and should be timed just before the weather will turn favorable for seeds to do so. Temperature and moisture are the chief factors. The chemical will not last a whole growing season and some seeds are hardier than others; so expect some weed seeds to sprout. Proper mowing height, mowing regularly enough to prevent the weeds from forming seeds and careful watering are some of the cultural activities which help to keep weeds from spreading.