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Search results on 06/19/13
4921. Oien, David. no date. Black medic information packet.. Timeless Seeds, RR 3 Box 461, Conrad, MT 59425.
This packet is sent to growers who purchase seed. The seeding rate is recommended at 8-10 lb/ac, planted 1/2" deep into a firm seedbed. Field trials have indicated successful medic establishment with barley, oats, spring wheat, and flax as nurse crops, but a second year of medic growth is then necessary for adequate seed production. On-going experiments in Montana (Jim Sims, MSU) are examining several rotations: medic-cereal, sweetclover-cereal, fallow-ceral, and continuous cereal, with different nitrogen rates. Results indicate that the green manures used 1-3" more soil moisture than the other treatments. Wheat yields after medic and sweetclover (25 bu/ac) were significantly higher than all other treatments. An herbicide screening tested a number of alfalfa herbicides on black medic. Poast, Fusilade, Treflan, and Kerb did not injure medic, while paraquat, Pursuit, and 2,4-DB ester caused minor injury. Solicam provided the best overall weed control with little injury to the medic.
7524. White, J.G.H.. undated. Grain legumes in sustainable cropping systems; a review.. unpublished manuscript, Plant Science Dept..
This paper briefly reviews the role that grain legumes can play in sustaining cropping systems. It presents various estimates of N fixation of grain legumes, with lupin and fababean showing the highest rates, followed by peas and lentils, chickpeas, and soybeans. Phaseolus beans are generally poor N fixers. Fababeans are more tolerant of soil mineral N than other species and will still fix large quantities of N when mineral N is present. Under drought stressed conditions, peas and lentils were more efficient in N fixation than fababeans. Only in lupins and fababeans was N fixation normally greater than the N removed in the seed. The roots and nodules of grain legumes are likely to be the greatest source of N for following crops. This N is often quickly mineralized within several weeks after harvest, and strategies are needed to prevent its loss. Grain legumes are also beneficial break crops, particularly for soil-borne diseases, and can help to control certain grassy weeds. Preceding grain legumes with a brassica crop has reduced the incidence of Aphanomyces root rot in peas, due to sulfur containing compounds. Most grain legumes suffer reduced yields if soils are compacted and poorly aerated. The paper contains numerous references and tables on nitrogen relations.
10059. Smith, L.J.. 1988. Regenerative agricultural systems in Nez Perce county.. unpublished handout, Univ. of Idaho/Nez Perce Cooperative Extension, Lewiston, ID.
This study was undertaken to evaluate, demonstrate and compare the competitive advantages associated with the use of green manure plowdown as a viable segment of regenerative systems in Nez Perce County. The greatest N return came from the yellow blossom clover and red clover mixture plowdown (191 lbs N), while two Austrian winter pea sites returned 116 and 92 lbs/ac N. Nitrogen carryover indicated that topdress N could have been reduced by 88% under the clover plowdown and up to 100% under one of the pea plowdowns. Yields of soft white winter wheat were 110 bu/ac following clover, and 82 and 100 bu/ac following the two pea plowdowns. Net return following clover was $214.85, and $94.63 and $123.35 for the two pea sites.