I’ve spent some time this week (May 31st – June 3rd) measuring and evaluating the development of 2nd-crop Alfalfa in SE Minnesota. I know it seems like we just finished up with 1st-crop but what I’m finding is most of 2nd-crop growth has an average canopy height of about 14” … with some at 12” (1st-crop cut May 18th – 20th), and some at 16” (1st-crop cut May 14th-15th). As per usual the taller plants within each stand are at least 2” above the average, so as things appear right now our current estimate of forage quality runs in a range from 230-260 Relative Feed Value. The weather forecast for the next 10 days looks very favorable to advance growth & maturity, with high temperatures from Wednesday June 8th through Sunday June 12th predicted to average above 80 degrees Fahrenheit, and only 1 day in that timeframe expected to have above a 50% chance of rain (Thursday June 7the during the A.M.). So it is plausible to expect that most of these stands will grow 7/8th to 1” per day over the next ten days leaving the tallest plants ranging from 23” to 27” total height. That leaves our PRE-harvest quality 10 days from now as high as 175 to 195 RFV if we haven’t yet established a visible bud, to as low as 170-185 if at least 1 node shows evidence of budding.
So I would encourage most of you to take a very close look at your stands or give myself or someone at All-American Co-op and Progressive Ag Center a call. We can help evaluate your particular situation. With any luck that our weather pattern goes as I have explained in this scenario we should plan to be out cutting 2nd-crop Alfalfa on most fields in SE Minnesota sometime between June 9th and June 15th ! Again remember that the harvesting process generally brings forage quality DOWN anywhere from a minimum of 10 to as much as 20 RFV points, so you need to take this into account as you look to plan your cutting date.
Additionally it is important to remember that with “warmer-evenings” plant maturity can occur much more quickly, with flowers & lignification developing at a much faster pace. Consider forage feeding with Boron or other applicable micronutrients if appropriate, and don’t forget “bug” control if it is needed. Most of us understand how much it costs to purchase Hay and other forage-replacement ingredients after working our way through many of the winterkill issues in the past. Remember that you can NEVER go back in time to improve forage quality once mother-nature sets it’s coarse … and that’s why I propose that you can never plan too far ahead for a good crop.