The main objective of these experiments was to study the effect of three levels of N fertilizer on the quantity and quality of late‐summer and autumn‐produced ‘Kenblue’ Kentucky bluegrass, Poa pratensis L., and ‘Kentucky 31’ tall fescue, Festuca arundinacea Schreb., forage left standing in the field during fall and winter. Information is needed on the extent to which stockpiled pasturage can serve as a reliable cheap source of feed for beef brood cows, dry dairy cows, and growing stock. Factorial experiments were conducted for three successive years. The trials involved two grasses, three N levels, and six stockpiling periods. Nitrogen fertilizer was applied in mid‐August, and the standing stockpiled grass crops were harvested in early October, November, December, February, and March. Regrowth herbage was harvested in May, July, and mid‐August, after which the experiments were terminated. Production from 15 Aug. to I Dec. on plots receiving 0, 50, and 100 kg/ha of N was 800, 1,800, and 2,300 kg DM/ha for Kentucky bluegrass and 1,900; 3,100; and 4,400 for tall fescue, respectively. At the high level of N tall fescue continued to accumulate dry matter at a significant level (17.7 kg/ha per day) during November. From December to March accumulated dry matter of the standing crops decreased, apparently owing to unfavorable growing conditions, weathering, and leaf drop. Swards of both grasses were high enough in crude protein and P throughout the winter to meet the requirements of non‐lactating beef brood cows. Generally, tall fescue contained more total sugar in late autumn and early winter than did bluegrass. Sward sugars of both grasses declined sharply as the winter advanced. Phosphorus concentration was high in October, November, and early December, but declined markedly during late winter. Estimated nutritive value indices of the standing forage decreased as the autumn and winter advanced. Fall and winter harvesting of stockpiled forage resulted in little or no yield reduction of the spring crop.

The utilization of Near Infrared Reflectance (NIR) spectroscopy by the forage and feed industry has been limited by the requirement that each instrument be individually calibrated. One possible solution to the problem is the transfer of NIR calibrations by computer from one instrument to another. Computer programs have been developed by our laboratory to accomplish this objective. We conducted research to test this software with seven NIR scanning monochromators. Sixty sealed samples were used in the transfer process. One monochromator was chosen to be the master instrument. Calibration equations developed on it were transferred to six slave instruments. The standard errors of difference including bias (SED) among instruments for crude protein, acid detergent fiber, neutral detergent fiber, lignin, and in vitro dry matter disappearance were less than SED among laboratories for chemical analysis. Satisfactory transfer was accomplished with as few as 10 samples. Computerized transfer of equations promises to be a satisfactory alternative to individual instrument calibration.

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Factorial experiments were conducted for three successive years with plantings of alfalfa (Medicago sativa L.) made in spring, mid‐and late summer of each year. White clover (Trifolium repens L.) was sown only in spring. Tillage levels were none and strips tilled to a depth of 1.9 cm with widths of 0.6, 1.9 and 5.7 cm. Herbicide levels were none and paraquat, l:l‐dimethyl‐4, 4'dipyridylium dichloride, applied at 1.11 kg a.i./ha in bands of 5.1 and 10.2 cm over the seeded rows. Seeds were placed either on or below the soil surface. Spring plantings were most successful, late summer ones were intermediate, and those made in mid‐summer were poorest. Placing the seed 1.2 (alfalfa) or 0.6 cm (clover) below the soil surface was found to be the most consistent controllable factor contributing to successful establishment. Stands were equal or superior on the minimumtilled plots i.e., strips 0.6 cm wide and 1.9 cm deep, to those of other treatments. Paraquat banded over the seeded row enhanced legume stands only when grass stands were dense and growth was rapid. Based on success with minimum tillage, a prototype field machine was designed and constructed to till, seed, cultipack, and apply herbicide in one pass over the land.

Botanical composition of swards can markedly affect their productivity, forage quality, and acceptance by animals. The objective of this research was to determine the amounts of dry matter (DM) and N harvested in the different botanical components of swards where perennial ryegrass and orchardgrass were sown alone and fertilized with N, or sown in mixture with legumes.Broadcast sowings were made on conventionally prepared seedbeds in August 1979 and May 1980 on a Hagerstown silt loam soil (fine, mixed mesic Typic Hapludalf). When seeded alone, orchardgrass cv. Pennlate and perennial ryegrass cv. Reveille received rates of N ranging year as birdsfoot trefoil harvested DM was lower in trefoil-ryegrass swards than in trefoilorchardgrass mixtures, probably owing to vigorous competition from ryegrass in the seedling stage. As legume seed rates were increased, both the legume and grass components of mixed swards produced more DM and N. Grass DM and N harvested in orchardgrass mixtures exceeded those of ryegrass mixtures for the 3-year period.Sward weediness, most prevalent in pure legume stands planted at low seed rates, was sharply reduced by including either grass with the legumes. Volunteer legumes contributed to DM harvested only when the grasses were sown alone and not fertilized with N.Species differences in crude protein (CP) concentration were significant. Birdsfoot trefoil had the highest CP of the legumes, averaging 241 g (kg DM)"'. Alfalfa and red clover averaged 219 and 208 g CP (kg DM)-' respectively. Perennial ryegrass herbage had a higher CP concentration than that of orchardgrass in both pure and mixed swards. Grass CP increased significantly in response to fertilizer N and to higher legume seed from 0 to 448 kg ha~' a"'. The grasses were also rates, grown in mixtures with alfalfa cv. Arc, red clover cv. Arlington, or birdsfoot trefoil cv. Viking. The same legumes were sown alone. Four legume seed rates were used in both the pure legume and mixed stands.Legume DM harvests were greater in mixtures with perennial ryegrass than in legume-orchardgrass swards. An exception occurred in the first