Knowledge or fertility requirements or nitrogen-use efficiency or amaranth (Anuzranihus spp.) cultivars is limited. The objectives of this research were to determine the response of grain amaranth to applied N, P, and K. and to determine the effect of cultivar and fertilizer N on nitrogen-use efficiency. Two field experiments were conducted. In the first, five rates of N, P, and K were applied in a central composite design with the cultivar Plainsman grown in five environments. In a second experiment, six amaranth cultlvars, Amont, K266, K283, Plainsman, K432 and 0136, were grown in three envi· ronments with five N rates (0, 45, 90, 135, and 180 kg N ba-1 ). There was no response to P and K applications wben initial soil tests were above 68 kg P ba-•, and 172 kg K ba-•, respectively, but grain amar· anth responded linearly to applied P at one location with Initial soil P tests of 11 kg ba-•. Grain yield ranged from 794 to 1980 kg ba-• and responded to N in most environments. Forage yield ranged from 6.1 to 16.6 Mg ba-• and was increased at higher N rates. At all locations, lodging increased with application of N. Fertilizer N increased pre-flowering N accumulation but not post-flowering N ac· cumulation. Nitrogen-use efficiency (NUE) ratio of grain yield to total soil N supply ranged from 3.48 to 7.91 kg kg-' across cultivars and environments. Nitrogen-use efficiency decreased with increased soil N mainly because of decreasing N-uptake efficiency (ratio of total plant N to total soil N). Grain amaranth is relatively inefficient in N-use primarily because of its low harvest index (ffi = 9-15%) and N bar· vest index {NID = 12-26%). This suggests that selection for higher m and NID could be effective in improving grain yield and nitrogen· use efficiency of grain amaranth.A MARANTII SPECIES produce a high protein seed (160-180 g kg) compared with other non-legume grain crops. When combined with cereal grains, amaranth provides a balanced amino acid composition for human consumption (Saunders and Becker, 1983). As a result, amaranth grain has been incorporated into a range of human-food products, which are primarily targeted at health-conscious consumers (Breene, 1991). It is a plant which also has potential in protein-deficient regions of the world.Amaranth grain yields differ significantly among cultivars and over environments. In Midwestern states, grain yield in replicated trials has ranged from 150 to 2500 kg ha-1 (Robinson, 1986;Weber et al., 1990). Lodging can be a severe problem in amaranth and is influenced by height, stalk strength, root morphology,

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The economic impact of intensive grazing for a representative Pennsylvania Holstein (Bos taurus) dairy farm was evaluated using a Monte‐Carlo farm level simulation model. Ten harvested forage combinations with or without intensive grazing of pasture were modeled. For each of 10 farm scenarios, least‐cost rations were developed to meet the requirements for the level of milk production. Net cash farm income, and the after‐tax net present value of ending net worth were used as profitability measures. The after‐tax net present value distributions of the 10 dairy farm scenarios were also compared using stochastic dominance analysis. Results showed that under the assumption of equal milk production level (IS 800 Ib/cow per yr) and depending on the forage crop mix, annual net cash farm income with intensive grazing increased by 14 to 25% compared with farms without intensive grazing. These increases translated into $8 400 to $12 400 more in annual net cash farm income for a typical Holstein dairy farm with a 60‐cow herd. The observed increase in income and profitability for farms with intensive grazing was largely due to the decreased cost of milk by an average of $1.20 to $1.42/cwt, depending on the forage crop mix analyzed. A risk assessment of intensive grazing using stochastic dominance analysis showed that most farms with intensive grazing were preferred to the nongrazing dairy farms under the assumption of equal milk production output per cow. When milk output per cow was allowed to fall for farms with intensive grazing, however, the stochastic dominance analysis showed that the robustness of the preference for intensive grazing depended on the harvested forage mix used. Milk yields could only drop from 4 to 6% before the grazing forage crop mixes were no longer preferred under risk. Research Question The current cost‐price squeeze faced by dairy farmers is prompting many to seek alternative forage feeding systems to control feed costs and improve profitability. Incorporation of intensive grazing into current forage feeding systems has gained increasing interest in the Northeast. The objective of the present study is to analyze the potential impacts of intensive grazing vs. harvested forage systems on profitability for typical Pennsylvania dairy farms. The study also compared the preference of forage systems with intensive grazing under risk and uncertainty. Literature Summary Little research has investigated the economic impacts of grazing‐based forage systems for U.S. dairy farmers. Most research on dairy grazing has emphasized either the nutritional impacts of grazing or the effects of grazing on milk output per cow and animal weight gain. Preliminary economic evaluations of the benefits of grazing in the Northeast have shown an average increase in net farm income of between $12l/cow (Pennsylvania) and $15Ucow (Vermont). Most of these studies have the same limitation, however, the use of partial cost approach leaving unaccounted for such factors as fixed costs, machinery costs, and labor requirement changes. A ...