June 6, 2013

When will you take your first cutting of alfalfa for hay? With so little carryover available, getting maximum tonnage may be extra important this year. 

The typical recommendation is to harvest at early or one-tenth bloom because that often gives the best balance between yield and quality.

This year, though, yield might be way more important than quality. If you need extra tonnage, wait until your alfalfa is at the full bloom stage of growth before taking the first cut. This occurs about 10 days after first blooms appear and can add about one-half ton to your first cut yield. If moisture is short, maximizing tonnage at first harvest is especially important because moisture is used more efficiently to produce yield during first growth than at any other time. If your alfalfa receives enough moisture to support regrowth through the year, harvesting three cuts at full bloom should give you about 10% more total yield than taking four cuts at first bloom.

Be sure to check fields closely when waiting to harvest alfalfa at a more mature growth stage. Walk through fields and look for new shoots beginning growth from the crown. Also watch for spring blackstem, a disease that can cause lower leaves to fall to the ground. If you find major occurrences of either of these issues, start harvest regardless of the amount of bloom on your alfalfa.

Mature alfalfa hay usually contains less protein than younger hay but still should be plenty adequate for wintering beef cows. For yearlings and heifers, though, higher quality hay might be preferred.

Bruce Anderson
Extension Forage Specialist