Thomas G. Chastain
Grass seed crop acreages in Oregon’s Willamette Valley have varied over time. One interesting aspect of the rise and fall of grass seed crop acreages in the region is their relationship with wheat acreages in the Willamette Valley. A rise in grass seed crop acreage is mirrored by a simultaneous fall in wheat acreage and vice versa, and these trends are evident in the graphic below.
Grass seed crop acreage is sensitive to general economic conditions and is reduced by recessions in the national economy (marked by gray bars). When prices of wheat and other crops are favorable for economic production during periods of low grass seed prices, there is a replacement of grass seed acreage by these crops. From the mid-1970s through the early 1980s, both crops occupied about 250,000 acres and together accounted for about 1/2 million acres in the valley. After the early 1980s, grass seed acreage grew while wheat acreage dropped – market conditions favored the rise of grass seed crops and decline of wheat in the valley over the next two plus decades. The most recent recession coupled with good prices for wheat gave rise to a growth in wheat acreage and a precipitous drop in grass seed crop acreage. A reversal of that trend is now underway as the economy slowly recovers.
Do all grass seed crops species experience these swings in acreage over time with wheat? The evidence suggests that only two species, perennial ryegrass and tall fescue, are primarily responsible for the broad gains or losses in grass seed crop acreage (see graphic below). Acreages of perennial ryegrass and tall fescue have increased dramatically over time but have declined again with the recession and general economic downturn of recent years. Losses in perennial ryegrass and tall fescue seed crop acreages during this downturn have been replaced by growers turning to wheat and other crops.
Acreages of annual ryegrass and Chewings fescue have remained stable over time and have showed little in the way of major acreage shifts. Annual ryegrass seed crop acreages have not varied appreciably because this crop is predominately grown on soils with drainage characteristics that do not permit economic cultivation of wheat or other crops. Chewings fescue is grown largely on hill sites where wheat and other crop possibilities are likewise limited because of steep slopes, erodible soils, and poor yield potential for cropping alternatives.
When market forces favor wheat over grass seed crops, Willamette Valley perennial ryegrass and tall fescue seed crops are replaced, at least in part, by wheat. Nevertheless, the long-term trends clearly point to an increase in the acreage of grass seed crops and loss of wheat acreage in the Willamette Valley.