April 3rd, 2012
Thomas G. Chastain
Several forage legume seed crops continue to be a vital part of seed production enterprises in the Willamette Valley. These include red clover, crimson clover, and white clover. Other seed crops that have been produced in the valley include ladino clover, arrowleaf clover, subterranean clover, hairy vetch, and common vetch.
Figure 1. Crimson clover in flower. (T.G. Chastain photo)
Seed yield of forage legume seed crops has increased over time in the Willamette Valley (Figure 2). Red and white clover yields have roughly doubled since the mid-1970s. Crimson clover seed yield on the other hand, has tripled in the same time. The reasons for the increases in seed yield are varied, but improvements in crop management and seed harvest are among the most important in these crops. Our current work suggests that more improvement in seed yield is possible.
Figure 2. Forage legume seed yield trends in the Willamette Valley. (click to enlarge)
Red clover has been the most widespread among the forage legume seed crops in the valley and is experiencing a bit of a resurgence in acreage (Figure 3). White clover seed crops have seen the greatest increase in acreage while crimson clover has been grown on fewer acres in the valley since the 1970s.
Figure 3. Legume seed crop acreage trends in the Willamette Valley. (click to enlarge)