Quality and Yield of Corn Plants and Component Parts when Harvested for Silage at Different Maturity Stages1

Abstract

AbstractThe influence of maturity and rainfall distribution on quality of component parts (ear, leaf, and stalk) and whole plants of corn (Zea mays, L.) harvested as silage was studied over a 3‐year period at Experiment, Georgia. Seven harvests were made at weekly intervals from the late milk to mature stage of the grain. In vitro dry matter digestibility (IVDMD) and total available carbohydrate (TAC) content of ears increased with maturity then leveled off, and IVDMD reached a maximum later (dough stage) than did carbohydrate content (early dough stage). The time of maximum ear IVDMD was delayed when adequate rainfall was received during the harvest period. Leaf IVDMD and TAC content generally decreased with maturity. Both IVDMD and TAC content of the stalks were closely related to the rainfall received during the maturing period, decreasing with maturity when rainfall was limited, increasing when rainfall was received after a drought period, or remaining constant when rainfall was well distributed. The changes noted in ear and stalk quality were reflected in whole plant quality. Green forage yields generally decreased with maturity, but when adequate rainfall was received before the dough stage this decrease was delayed. Dry forage yields increased until the fourth harvest then decreased with maturity. Ear content increased until the dough stage then leveled off, while stalk content decreased to this stage then leveled off. Leaf content generally decreased with maturity.