Drought Stunted Alfalfa - Cut or Leave — First the good news while it stays dry you can do whatever you feel like doing and you aren't likely to hurt your alfalfa. The bad news is that if it stays dry you won't do it much good either. So my recommendation is to use it or lose it.
As your alfalfa continues to just sit there dormant, it will slowly lose feed value and tonnage due to continued maturation as well as leaf loss from insect feeding, diseases, and simple old age.
You probably need a yield of at least one-half ton per acre to justify the fuel, labor, and other expenses involved with harvesting hay. Grazing might be relatively cheap in terms of out-of-pocket costs if you already have portable electric fence and don't need to transport cattle or water. And dry, bloomed out alfalfa has a pretty low risk for bloat ? not foolproof, but common sense animal husbandry should enable you to graze safely.
If you can't hay or graze, it's probably best to just leave it alone. Shredding will give you a cleaner, higher quality hay once your alfalfa receives enough rain for regrowth and it probably will start regrowing just a bit faster. But in most cases, it's not worth it when the cost and time involved in shredding are considered.
So pick the option best for you, and let's all pray for rain.
Planning That Last Cutting of Alfalfa — As we approach September, it's time to decide when to take your last cutting of alfalfa.
The date you take your last harvest of alfalfa affects its winter survival and next spring's vigor. Alfalfa needs about six weeks of uninterrupted growth in the fall to become fully winterized. This winterterizing generally begins about three weeks before the average date of first frost. Your last harvest can occur anytime before winterizing begins or after the winterizing period is over with little worry about affecting stand life. But, harvest during winterizing can be risky.
How risky is it to harvest alfalfa during winterizing? Well, that depends on how much total stress your alfalfa experienced this year. The most important factor is the number of cuts you took this year. Fields cut 4 or 5 times are more susceptible to winter injury than fields cut 3 times or less. Also, young stands of winterhardy, disease resistant varieties are less stressed and can be harvested during winterizing with less risk than older stands of disease susceptible varieties that are only moderately winter hardy.
Also consider your need for extra alfalfa or its value as a cash crop. Hay is short in some areas, so the extra hay you cut from this final harvest may be worth the risk of lowering next year's yield. But, if you have plenty of winter forage and don't have a good market for any extra, maybe the risk is too high. Remember, you also can cut after winterizing with less risk.
Harvesting alfalfa during its winterizing period is risky, but by reducing total stress, you control how risky it is.
When To Rotate Alfalfa — How do you decide when one alfalfa field has run out of steam and a new one needs to be planted?
When should you rotate to a new field of alfalfa? One obvious answer is when the stand gets too thin. Okay, then, what is too thin? I use a couple guidelines. One is density of alfalfa plants. Older, dryland fields should have 30 or more shoots coming from 2 or more plants per square foot to be worth saving. Irrigated fields need 40 shoots from 3 or more plants. If your stand is thinner than these guidelines, look for somewhere to start a new field next spring.
Also look at weed density. Are your fields getting weedier each year? Are many of the problems perennial plants like bluegrass, dock, or dandelions? This can suggest an alfalfa stand that lacks the vigor or density needed to compete. A new field should be considered.
Alfalfa stands, though, sometimes last a long time. But just because your stand is thick and weeds aren't a problem doesn't mean you should keep the field another year.
For instance, many dryland fields yield well for several years. Once they have exhausted all available subsoil moisture, though, yields drop even though stands may remain thick. In these fields, yield is limited only to what annual rainfall can support and many dryland fields now have reached this stage. Rotating to a new field can provide a fresh source of deep subsoil moisture. And don't forget that the crop that follows alfalfa will get some free nitrogen as well as a rotation-based yield boost. Rotating alfalfa through your fields just a little more frequently will give you this boost more often.
Think about these factors as you decide whether to start new alfalfa next year or not.
Source: Bruce Anderson, UNL Extension Forage Specialist
