Effect of Spring Harvest Date on Nutritive Value of Orchardgrass and Timothy

Digestibility of orchardgrass and timothy generally decreased with advancing maturity of the plants in spring. Dry matter intake of forage cut about May 20 was as high as for that cut during the first week in May. Delaying harvest until June 12 or 13 reduced intake by about 27%. Late maturing varieties of timothy and orchardgrass were slightly higher in dry matter digestibility than early maturing varieties cut on the same date. In take was similar for the two varieties within each species. Forages harvested on comparable dates were more digestible in 1963 than in 1964. Dry matter and energy digestibility were closely related to leaf percentage and protein content of the forage. Intake could not be predicted from these two characteristics. Leaf content appeared to be a better indicator of digestibility than harvest date.