EPTC can aid in the establishment of seeded annual clovers in dryland pastures where a weedy annual grass problem exists. Trials conducted in Mendocino, Mariposa, San Benito and Santa Barbara counties indicate that the pre-emergence herbicide will reduce competition from annual grasses but not from forbs such as mustard and filaree. Success is still dependent on climate, fertilizer treatment, grazing use and other related factors. EPTC application provides a method of altering species composition of a pasture. It can be applied in the late summer to prevent seed germination, in contrast to many herbicides that must be applied to living plants.

The EPTC used in the study was supplied by Stauffer Chemical Company. Assisting with some of the field work were Rocky Lydon, San Benito County; Ray Greberger, Santa Barbara County; and John Anderson, Mariposa County—Farm Advisors, Agricultural Extension Service.