Floret and Seed Types in Kentucky Bluegrass in Relation to Yield and Quality of Seed 1

~I of the seed crop of Kentucky bluegrass from the KentuckyOhio area is produced on a relatively few farms in the central bluegrass region of Kentucky. Even on these: le£ding seed-producing farms, however, bluegrass is seldom, if ever,, grown primarily for seed. It is grown rather for pasture and for conditioning land for tobacco, and the seed is harvested to provide a supplementary income when the bluegrass field is not needed exclusively for pasture during the spring. The amount of seed harvested;, therefbre;, varies greatly from year to year. Four crops of over 9oo;ooo l~usl~ets of rough-cured Kentucky bluegrass seed have been produced! iWttie Kentucky-Ohio area since 1925 and five crops of 2oo;ooo 15ushelk~o~;l~ss:~ The average yield per acre of the former was ~3.5; lJushelg: and:., of ~¢he latter 4;7 bushels. Acreages harvested in producing tl~l~/rg~er c~ops’ranged from 92,857 to 135,294, and those harvested’ ii~ pr0dhcihg the smaller ranged from i5,ooo to 43,75o. The averages for the two groups were lO7,o38 and 29,173 acres, respectively. The average seasonal prices paid to growers for the rough-cured seed were 8o cents and $I. 13 per bushel, respectively, for the larger and smaller crops. In other words, farmers harvest large acreages when the yield per acre is high; small acreages when the yield per acre is low, and receive lower prices per bushel for their large crops than for their small crops. At the time seed stripping begins, farmers have a reasonably accurate opinion of both the price which the seed will bring and the average yield per acre that may be expected. Since it is clear from the information just presented that price per bushel has little or no influence in determining the size of the seed crop produced, it may be concluded that when yield per acre is good a large acreage is harvested and when low a small acreage is harvested. The percentage of marketable seed in the rough-cured seed (Fig. x), commonly designated as "clean-out" percentage, is a good measure of the quality of rough-cured seed. The best quality seed has a "cleanout" of 60 to 65% and low quality seed 4o% or less. Thus defined, quality of rough-cured seed has varied widely, especially during the last 5 years when the extremes have been 55% and The quality of rough-cured seed seems to be closely correlated with yield per acre. Four crops producing an average yield of 11.4 bushels per acre had an average clean-out of 55%, and three crops producing an average of 4.7 bushels per acre cleaned out 4o.8%. In a statistical analysis of the acre yield and clean-out of nine crops for which data