What about now?
Aug 25, 2016
ALFALFA. How about now?
Most folks in the Northeast learned how to make hay by watching and helping their father and grandfathers. Most hay producers start cutting hay about 10 a.m. By then, the dew is burned off providing the shade from our neighbors hedgerow isn’t prohibiting that, and once the sun is able to cover all downed hay for approx. 30 minutes it was just right to start cutting hay.
Obviously conditions in the Northeast are different than in the Southeast or Northwest. So which is the right time to cut hay? Is there a right time to mow hay, more specifically the coveted Alfalfa? Alfalfa hay will yield 5 to 8 tons per acre per year during seasons with “good” moisture. Good varieties like we use (but can’t mention), in addition to proper moisture and well drained soil, can make a seeding prolific for 3 to 8 years
Harvesting alfalfa at the 1/10 bloom stage provides the best compromise between yield and quality. At this maturity, alfalfa consists of 50% leaves and 50% stems. Early harvest increases the leaf portion; leaves comprise more than 80 percent of alfalfa that is 4 to 5 inches tall. Harvesting at this immature stage provides extremely high-quality forage but low forage yields. The stand is also likely to be damaged. The leaves contain 2/3 of the protein and 75% of the total digestible nutrients (TDN) in alfalfa hay.
Cut only the alfalfa hay in one day that you know you can bale in one day. Our discbine cuts hay so rapidly it is easy for me to lay down more hay in a swath than can be raked before leaves begin shattering.
Most producers want to capture their forages at the peak of it’s growth stage and yes, there is an optimal time of day to mow and bale. Let’s start by examining the amount of sugar v.s. starch in our forage crop.
All our forages will go through a daily cycle. Regardless of where in the country the crop or forage is grown, the plant creates carbohydrates during the daylight hours via the process of photosynthesis. This is something we all learned about way back in 4th grade. The photosynthesis that occurs during the day is at a rate that is higher than the plant needs for growth and maintenance during the day. So, sugar content will generally be highest at dusk. Though starches and simple sugars accumulate during the day, a substantial amount of these carbohydrates are used up during the night for growth. Therefore, cutting the crop at night will likely maximize the sugar in the crop, at least at the time of cutting. However, the difference in sugar content between late evening and early morning is relatively minor.
It’s a nice way to say dying. Respiration by the plant does not stop whenever the crop is cut. In fact, the moisture in the crop has to drop below 47% moisture for respiration to totally cease. In the sometimes unbearably humid Northeast , the crop moisture in the field can take up to 2 days to go from 85% moisture to less than 47% moisture especially with straight alfalfa stands. For that reason, most of us will interseed Orchardgrass or a fescue grass to aid in the drying process by adding layers of quicker drying grasses that will help air circulation throughout the windrow of alfalfa/grass mowed hay. In the heartland or arid mid-west where extreme humidity isn’t a key player in making hay, moisture can drop from 85% - 47% in a matter of hours.
Weather Risk Trumps Timing
The greatest risk to hay curing and forage quality is of course rain. Weather prediction is, obviously, far from perfect or even somewhat accurate from hour to hour depending on your location. If the weatherperson says there is no chance of rain in the 48-hour forecast, say a prayer and take a chance. Unfortunately, unless you have 48hours of weather with 20% humidity, you’ll never get alfalfa mowed, raked and baled so that it will safely cure and store .
After 1st cutting, aim for subsequent cuttings to be made every 30 to 35 days. Beginning in June, the moisture requirements of alfalfa are typically greater than that supplied by rainfall. Irrigation can boost yields but obviously isn’t an option for all producers. Drought stunts most alfalfa growth and may cause it to yellow or even “burn up.” Increasing the harvest interval period is the only alternative during summer droughts like we’ve experienced this summer.
Wrapping it up
Careful final cutting preparations of your alfalfa will allow the stands to build adequate root reserves for winter survival. Don’t graze or mow alfalfa during the 20 to 30 day period in the fall immediately before the first killing frost. Around here that could be as early as Labor Day. To help ensure vigorous alfalfa stands for several years, allow the foliage to transfer nutrients to the roots during the month prior to winter dormancy. This raises the level of carbohydrates in the roots to nearly 40%, enough to supply winter root reserves and to support vigorous green-up in the spring.
In closing, the answer to the question of "When is the Right Time to mow Alfalfa?" is that it is usually best to start cutting hay as soon as possible during the morning. As with any such generalization, there are always some exceptions, such as if you’re a dairy farmer and your going to be chopping it the same day or 24hrs. after mowing? Look folks, I’m not a gambling man, but I guess all of us in agriculture take a gamble everyday when we try and plan our day’s based around the worlds most unpredictable circumstances, Government aside, let’s just try and make the best of each day, think ahead, be safe, do what’s right, and pray. Pray allot!!