Michigan State University Turfgrass Scienceturf.msu.edu

Poison Ivy Control

Aug 10, 2010 at 12:20pm  —  Ronald Calhoun

The cool evenings of the past week have been welcome releif to turfgrass managers and those without air conditioning. Sleeping with the windows open and waking up in the morning to heavy dew are sure signs that summer's stranglehold will soon be loosened. The record heat of 2010 started back in March. This has been great for things like crabgrass, goosegrass, and other summer annual weeds. If you live near a woodlot or naturalized area you may have noticed that 2010 has also been a remarkable year for poison ivy growth. Poison ivy is one of the most common causes of blistering dermatitis in the midwest and northeast regions of the country. If you are going to try and control poison ivy with herbicide applications then now is the time to start. Cool nights are a trigger for the vines to start storing energy for next year's campaign. Soon the leaves will turn crimson red and fall to the ground. Therefore, the first herbicide application must be made before the end of August in order to get good translocation into the vine and root system. Herbicides containing 2,4-D and triclopyr are the most effective on poison ivy. Extra caution should be used to avoid applying these product to adjacent broadleaf vegetation. Two applications, 3 weeks apart should provide a substantial reduction in returning plants next spring. Spot treating in late April, early May may be necessary to remove persistant plants. The irritating oil of poison ivy is present in all plant parts and will persist in dead vegetation for over a year. Take precautions when handling any plant parts or clothing that has come into contact with the vines.