Alfalfa Yield Response to Cutting Height and Cutting at Dawn and Dusk

Alfalfa yield and quality can be affected by the height and timing of cutting. This research was conducted to determine if 1) raising cutting height from 2 to 4 inches could increase stem density particularly during the summer months, and if 2) alfalfa cut at dusk and the following dawn differ in dry matter yield. Alfalfa was harvested from small plots eight times during the year in an experiment conducted at the Maricopa Agricultural Center in 1999 on a third year stand. The 4 inch cutting height resulted in consistently lower yields compared to the 2 inch cutting height even during the summer despite having slightly higher stem density. The 2 inch cutting height produced 12.5 tons/acre over the year compared to 9.9 tons/acre for the 4 inch cutting height. Forage yield was 3.7% higher for alfalfa cut at dusk compared to the following dawn. Alfalfa cut at dusk and weighed the following dawn lost a similar amount of dry weight overnight compared to alfalfa left standing. Any yield advantage of cutting at dusk can only be realized by greenchopping and immediately feeding the forage