Aphanomyces root rot (ARR) is a serious disease of both recently seeded alfalfa and established alfalfa stands.  ARR can cause severe yield reductions in affected alfalfa fields.  Variations of the disease also occur on many other legumes (including soybean, snap bean, faba bean, red kidney bean, pea, red clover, and white clover) and can cause significant losses in these crops as well.

The decision to take a late summer or fall cutting of alfalfa should be considered carefully. A farm should evaluate current forage needs, economics, stand health, and timing to make the best decision for their individual situation. Although the need for more forage may override some other factors, the timing of harvest is still critical. […]

While farming in the ‘North’ brings the benefits of growing some of the best forages like alfalfa and cool-season grasses, it also carries the weight of fall decisions that will ‘make or break’ your profit due to risks of winter injury. Fall decisions regarding alfalfa production include proper harvest timing  and providing adequate potassium, leading to strong plants that can survive a severe winter and come back the following year with good yield potential.