Production Update:

Stand Replacement: The decision to replace alfalfa stands is based on stand establishment costs, opportunities in other crops, hay price, and yield of the alfalfa stand in question. Historical yields for the farm can provide a good idea whether or not a stand should be replaced. A stand should be replaced if plant density is less than 4 to 6 plants per square foot or if the number of stems is less than 40 per square foot. Optimum plant density can be considerably higher if the plants are not distributed uniformly. Renovating alfalfa stands by overseeding with alfalfa is rarely effective except in relatively large bare sports. Delay seeding alfalfa into a field previously in alfalfa by 2 to 4 weeks to avoid autotoxicity.

Insect Management: Cowpea aphid (picture) can be a pest of seedling alfalfa. Cowpea aphid is the only black aphid found in our alfalfa. When stands of alfalfa become heavily infested with cowpea aphid, an insecticide treatment may be warranted to prevent stunting and leaf drop, and to prevent honeydew and sooty mold contamination. Treatment thresholds have not been established for cowpea aphid on alfalfa.

Weed Control: Although the mode of action and chemical composition of the grass herbicides, Poast, Select, Fusilade, Assure and others, are very similar, their activity on certain grasses varies. Sprangletop, for instance, is not controlled by Poast but is by Select.

10 Year Summary (Sept 3, to Sept. 20, 1995-2004):

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