proximately 70% of the broiler chickens produced nationally in 1999 were produced in Arkansas, Georgia, Temperate forages are used throughout the southeastern USA to Alabama, Mississippi, North Carolina, Texas, Tennesprovide feed for livestock when tropical and subtropical grasses are dormant and as a hay source. Long-term utilization of broiler litter see, and South Carolina (Natl. Agric. Statistics Serv., as a fertilizer in some areas of the region has elevated soil levels of 1999). A large proportion of the litter (a mixture of P and micronutrients. Our objective was to compare P, Cu, and Zn manure, wasted feed, feathers, and wood shavings or uptake among temperate forage species from a Savannah fine sandy other crop residue) is applied to hay fields and pastures. loam soil (fine-loamy, siliceous, semiactive, thermic Typic Fragiudult) Litter application may occur anytime during the year, amended with litter under a single-harvest system. Dry weight of depending on when a flock is removed from the house. ryegrass (Lolium multiflorum Lam.) herbage was greater than all If litter is applied to a dormant perennial or dead annual other species except ball clover (Trifolium nigrescens Viv.) in 1997 and tropical grass hay field or pasture during the winter and oat (Avena sativa L.) in 1998. Clovers were susceptible to Sclerotinia spring, the presence of an actively growing temperate crown and stem rot (Sclerotinia trifoliorum Erikss.) that reduced forage will reduce the potential for P loss, largely by plant density, vigor, and dry herbage weight. Although forage P concentration of all species was similar to or greater than ryegrass, only reducing sediment movement in runoff (Sharpley et crimson clover (T. incarnatum L.) had P uptake equal to ryegrass al., 1994). during both years (mean of 23.4 kg ha Ϫ1 ). This was attributed to the Frequent litter application also contributes to the achigh correlation between dry herbage weight and P uptake (r ϭ 0.95 cumulation of P and metals in the soil such as Cu and and 0.89 in 1997 and 1998, respectively). Legumes typically had greaterZn, which are added to poultry diets to improve weight Cu and Zn concentrations than ryegrass, but only crimson clover and gain and prevent diseases (Han et al., 2000). A benefit hairy vetch (Vicia villosa Roth) had comparatively greater Cu and of utilizing temperate species is that when harvested for Zn uptake during both years. The combination of desirable agronomic hay, they provide a means of exporting these minerals traits and nutrient uptake capacity make annual ryegrass a superior from fields where manure is applied (Brink and Rowe, temperate forage species for use in southeastern pastures fertilized 1999). Temperate forages can thus serve in both a feed with broiler litter. and nutrient management role (Daniel et al., 1998) in hay and pasture systems receiving broiler litter as a fertilizer source.

Formulating grass-legume mixtures requires knowledge of how the proportion of species in a seed mixture (i.e., species evenness) affects productivity and weed abundance. We hypothesized that mixtures with more equal proportions of species in the seed mixture (i.e., greater species evenness) would have greater productivity and fewer weeds than mixtures dominated by one or two species or monocultures. Two experiments with 15 mixtures and monocultures of orchardgrass (Dactylis glomerata L.), quackgrass (Elytrigia repens L.), alfalfa (Medicago sativa L.), and white clover (Trifolium repens L.) (Exp. 1) or 15 mixtures and monocultures of meadow fescue [Schedonorus pratensis (Huds.) P. Beauv.], reed canarygrass (Phalaris arundinacea L.), red clover (T. pratense L.), and kura clover (T. ambiguum L.) (Exp. 2) were sown in autumn 2008 at four locations in Pennsylvania and Wisconsin. In each experiment, there were four monocultures, four mixtures dominated by one species, six mixtures dominated by pairs of species, and one equal mixture. Mixtures and monocultures were harvested four to five times each year from 2009 to 2011. Mixtures often had more biomass than the average of legume or N-fertilized grass monocultures. Mixtures with more equal proportions of species in the seed mixture, however, did not have more biomass or fewer weeds than other mixtures. Rather, differences in yield were related to the dominant species in the mixture. Optimal legume percentages (30-40%) in the harvested biomass were achieved with a wide range of grass and legume seed proportions, which suggested that farmers have wide flexibility in formulating seed mixtures for pastures.

Near infrared reflectance Spectroscopy (NIRS) technology needs verification as to its utility for forages that represent diverse species, environments, and managements. Our objectives were to determine whether single NIRS calibration equations could reliably assess components of the feeding quality of alfalfa (Medicago saliva L.) grown to a range of maturities in several environments and whether single equations could be developed to simultaneously analyze components of the quality of total forage and plant parts of alfalfa, birdsfoot trefoil (Lotus cornieulattis L.), red clover (Trifolium pratense L.), and white clover (Trifolium repens L.). In the first experiment, we assayed four forage quality components in 234 alfalfa samples from eight cutting schedules of two cultivars grown in two locations in each of 2 years. In Exp. II, we assayed five quality components in 167 samples of total forage and plant parts selected from seven harvests from two growth periods of two cultivars of each of four perennial legume species. Calibration equations for in vitro digestible dry matter (IVDDM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL) were obtained by multiple linear regression of known conventional laboratory assay values on NIR spectra from up to 204 samples using a scanning monochromator NIR spectre‐computer system. Equations were validated with up to 49 additional samples that had been selected from the original populations. From three to nine wavelengths were required to develop the best calibration equations for the various quality components. The squared coefficients of determination (R2) of these equations ranged from 0.93 to 0.99. These equations allowed NIRS analysis of quality values in verification samples within standard errors (dag/kg) of 1.56 to 2.06 for IVDDM, 0.42 to 1.0 for CP, 1.46 to 2.23 for NDF, 1.30 to 1.70 for ADF, and 0.63 for ADL. We concluded that our NIRS system can quickly evaluate the feeding quality of perennial legumes to a degree of accuracy similar to that of laborious conventional analyses and that several species can be evaluated simultaneously with single calibration equations nearly as well as can single species.

Land application of poultry litter provides essential nutrients for hybrid bermudagrass [Cynodon dactylon (L.) Pers.] production, but ammonia (NH 3) volatilization and N mineralization influence the amount of litter N available for plant uptake. Our objective was to determine the combination of broiler litter and fertilizer N, which maximizes the yields of forage and N, P, and K by 'Coastal' bermudagrass. Studies were conducted for 3 yr (1999-2001) in pastures at Newton and Mize, MS that differed widely in soil test P (STP) due to history of litter application (0 vs. 301 yr, respectively.). Litter rates of 0, 4.5, 8.9, 13.4, and 17.9 Mg ha 21 were obtained by up to four monthly (April-July) applications of 4.5 Mg ha 21 and were supplemented with ammonium nitrate (NH 4-NO 3) to provide the same total N in each treatment. At Newton, combining litter with fertilizer N increased forage yield by 10% in 1999, 25% in 2000, and 34% in 2001, as compared to fertilizer N. At Mize, K uptake increased as litter rate increased in 2001 only. These responses to litter were related to increased soil P and K at Newton, and increased soil N, P, and Ca at Mize. Averaged across years, maximum P uptake of about 40 kg ha 21 was obtained by applying 8.9 Mg litter 1 134 kg N ha 21 at Newton and 4.5 Mg litter 1 202 kg N ha 21 at Mize. Safe and effective management of major plant nutrients in broiler litter may require the use of commercial N fertilizer.

Poultry litter used as fertilizer for forages often results in nutrient accumulation in soils over time. Maximizing nutrient uptake by forages would facilitate nutrient removal from litter‐treated soils when the plants are mechanically harvested. This study compared N, P, K, Cu, and Zn concentrations and distribution in plant parts of annual ryegrass (Lolium multiflorum Lam.) with 15 other cool‐season forages fertilized with poultry litter. Annual ryegrass, three cereals, and 12 legumes were seeded in a pasture at Collins, MS, on a Savannah fine sandy loam (fine‐loamy, siliceous, semiactive, thermic Typic Fragiudult) fertilized with poultry litter. Each species was harvested at full maturity and separated into root, stem, leaf, and flower components, and N, P, K, Cu, and Zn concentration and content of each component was determined. Most legumes had greater P, Cu, and Zn concentrations than annual ryegrass in many plant parts. Content of P, Cu, and Zn was similar between annual ryegrass and legumes due to greater dry matter yield of annual ryegrass compared with legumes. Stems, especially oat (Avena sativa L.) stems, had the lowest N/P ratio of all plant parts, which was more comparable to the N/P ratio of poultry litter. Nitrogen concentration was highly correlated with P, Cu, and Zn concentrations in aboveground plant parts, suggesting that improvements in N fertility would improve P, Cu, and Zn concentration in plants. To maximize P uptake in poultry litter–fertilized forages, management practices and breeding objectives should concentrate on optimizing stem production, while maintaining palatability, because almost 60% of total P in forages is located in stems.

The use of triticale (X Triticosecale Wittmack) in dairy-cropping systems has expanded greatly in recent years, partly to improve land stewardship by providing winter ground cover. Our objective was to establish relationships relating indices of nutritive value with growth stage or accumulated growing degree days >5°C for triticale forages grown in central Wisconsin. Replicated 3.7-m × 9.1-m plots were established following removal of corn for silage (fall 2015) and soybeans (fall 2016) and then harvested at various growth stages the following spring. Plants were assigned a numerical growth stage based on a linear staging system suitable for use as an independent regression variable. Response variables [e.g., dry matter (DM) yield, indices of nutritive value, and parameters from in vitro DM disappearance kinetics] were regressed on growth stage and growing degree days using linear, quadratic, cubic, or quartic models. For spring 2016, the mean DM yield at the boot stage (3,804 kg of DM/ha) was only 30% of that observed at the soft dough stage of growth (12,642 kg of DM/ha). Although yields were reduced during spring 2017, primarily due to spring flooding, the relationship between respective yields at these growth stages was similar (1,453 vs. 5,399 kg of DM/ha). Regressions of DM yield (kg/ha) on growth stage for 2016 were explained by a cubic model (Y = 0.0663x - 9.44x + 595x - 9,810) compared with a simple linear response for 2017 (Y = 103x - 3,024); in both cases, coefficients of determination were very high (R ≥ 0.934). Many nutritional and in vitro DM disappearance characteristics were affected by the juxtaposition and balance of 2 generally competing factors: (1) increased concentrations of structural plant fiber coupled with concurrent lignification as plants matured and (2) the accumulation of highly digestible carbohydrate during seed head development. A comparison of respective energy yields between the boot and soft dough stages of growth for 2016 (2,488 vs. 8,141 kg of total digestible nutrients/ha) and 2017 (1,033 vs. 3,520 kg of total digestible nutrients/ha) suggests that yields of energy are greater at soft dough stage and are mostly driven by DM yield. An informed harvest management decision for lactating cows may still favor a boot-stage harvest because of superior nutritional characteristics, a need to plant double-cropped corn expeditiously, or both. Harvest timing of triticale forages for other livestock classes would appear to be more flexible, but prioritizing a subsequent double crop may reduce the effects on DM yield to a secondary consideration.

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