Asparagus (Asparagus officinalis) is a perennial crop that has a 12- to 20-year production life in the field. Herbicides are applied in the spring each year and again after final harvest in early summer. Asparagus yield declines with age, and herbicides may contribute to yield decline. An experiment was established in 2004 and maintained for seven years with the same herbicide treatments applied each spring to determine herbicide effects on marketable spear yield. Spring-applied diuron, metribuzin, terbacil, sulfentrazone, halosulfuron, mesotrione, and clomazone had no adverse effect on yield or quality over the seven years of the experiment. Flumioxazin reduced yearly average marketable yield compared with standard treatments, and some spears developed lesions early in the season after rainfall. Asparagus yield from most treatments declined more than 50% from 2004 to 2010.