• Cattle trampling of simulated ground nests in rotationally grazed pastures

      Paine, L.; Undersander, D. J.; Sample, D. W.; Bartelt, G. A.; Schatteman, T. A. (Society for Range Management, 1996-07-01)
      For many grassland songbird species, pastures represent some of the best available breeding habitat in the Upper Midwest. Increasing interest in intensive rotational grazing (IRG) among midwestern livestock farmers may result in an expansion of pasture hectares in the region. We evaluated the effects of several cattle stocking densities on ground nest survival in rotationally grazed cool-season pastures in southwestern Wisconsin. Ground nests were simulated with clutches of 3 unwashed pheasant eggs. We tested 3 rotational grazing systems: a 1-day dairy rotation stocked at 60 head ha-1; a 4-day beef rotation at 15 head ha-1; and a traditional, non-intensive 7-day rotation at 8 head ha-1. Paddock size (1.2 ha) and nest density (15 nests paddock(-1)) were held constant. The simulated nests were observed 4 times day(-1) to document trampling patterns during the herds' diurnal grazing and rumination cycles. Trampling damaged a mean of 75% (+/- 3.1%) of the nests for all 3 treatments during 8 consecutive replications. While the 7-day treatment exhibited a pattern of greater nest trampling during cattle grazing periods than during rumination periods, this pattern was less evident in the 4-day treatment and absent in the 1-day treatment. Increasing vegetation height-density and percent vegetation cover were associated with reduced nest trampling rates, but pasture forage production and removal were not associated with nest damage.
    • Effects of Adenosine Monophosphate on Germination of Forage Species in Salt Solutions

      Undersander, D. J. (Society for Range Management, 1986-01-01)
      Seed germination can be a limiting step in the establishment of plant species on saline soils. There are indications that the level of adenosine monophosphate (AMP) in the seed may be a limiting factor in seed germination under stress. The objective of this research was to determine if added AMP would improve germination of grass and legume seeds under saline conditions. The seeds of tall fescue (Festuca arundinaceae Schreb. 'K-31'), bluegrama [Bouteloua gracilis (H.B.K.) Lag. ex Steud.], crested wheatgrass [Agropyron cristatum (L) Goertn 'Nordan'], switchgrass (Panicum virgatum L. 'Blackwell'), perennial ryegrass (Lolium perenne L. 'Lynn'), tall wheatgrass [Agropyron elongatum (Host) uv. 'Platte'], Russian wildrye (Elymus junceus Fisch.), western wheatgrass (Agropyron smithii Rydb.), and alfalfa (Medicago sativa L. 'Dawson') were germinated in petri dishes at varying levels of salinity with and without AMP. Time required for germination was shortened for all species, except switchgrass and western wheatgrass, with added AMP. Percent germination of alfalfa was increased with AMP at 14 days in 0.068 M sodium chloride and of tall fescue in the same concentration of sodium sulfate (dibasic). Perennial ryegrass, Russian wildrye and alfalfa demonstrated similar responses at 0.102 M sodium chloride. The germination of alfalfa was improved with AMP at 14 days in 0.034 M sodium sulfate. Adenosine monophosphate tended to have little effect when severe germination depression occurred from high salt concentrations.
    • Influence of Clipping Frequency on Herbage Yield and Nutrient Content of Tall Wheatgrass

      Undersander, D. J.; Naylor, C. H. (Society for Range Management, 1987-01-01)
      Grazing or cutting frequency has been shown to affect yield and quality of many grasses, but similar data are lacking for tall wheatgrass [Agropyron elongatum (Host) Beauv. 'Jose']. The objective of the research was to determine the effect of frequency of clipping on tall wheatgrass. The study was conducted at the Texas Agricultural Experiment Station at Bushland, Texas, in 1979, 1980, 1981, and 1984 on a Pullman clay loam soil. Plots were irrigated as needed from February to the end of the growing season and fertilized with 112kg N/ha every 2 months for maximum yield and clipped either every week, 2 weeks, of 4 weeks at a 5-cm stubble height. Herbage yield was highest from spring harvests and declined over summer as is typical of cool-season grasses. The plots that were clipped every 4 weeks produced greater herbage yields than plots that were clipped 1 or 2 weeks, suggesting that rotational grazing would increase productivity. The nutrient content of the herbage was highest during summer when herbage yield was lowest. Plants clipped less frequently had the highest concentrations of phosphorus and potassium and the lowest concentrations of calcium and magnesium. The greatest differences in nutrient content occurred among years, which emphasizes the importance of continual herbage analysis to optimize mineral supplementation of grazing cattle.
    • Prediction of leaf:stem ratio in grasses using near infrared reflectance spectroscopy

      Smart, A. J.; Schacht, W. H.; Pedersen, J. F.; Undersander, D. J.; Moser, L. E. (Society for Range Management, 1998-07-01)
      Leaf:stem ratio of grass stands is an important factor affecting diet selection, quality, and forage intake. Estimates of leaf:stem ratios commonly are based on a labor intensive process of hand separating leaf and stem fractions. Near infrared reflectance spectroscopy (NIRS) has been used successfully to predict forage quality and botanical composition of vegetation samples. The objective of this study was to evaluate the use of NIRS to predict leaf:stem ratios in big bluestem (Andropogon gerardii Vitman), switchgrass (Panicum virgatum L.), and smooth bromegrass (Bromus inermis Leyss.). A total of 72 hand-clipped samples of each species was taken from seeded monocultures in eastern Nebraska throughout the 1992, 1993, and 1994 growing seasons. Leaf:stem ratio was determined first for each sample and then the entire sample was ground. Samples were scanned by a Perstorp model 6500 near infrared scanning monochromator. Three calibration equations were developed based on using 18, 36, and 54 (1/4, 1/2, and 3/4 of total samples, respectively) samples. These 3 calibration equations were used to determine the number of samples necessary to achieve an r2 of 0.70 or higher for each data set. Big bluestem and switchgrass had coefficients of determination (r2) of less than or greater than 0.69 for all calibration equations except for the equation using only 18 samples of big bluestem r2 = 0.60). Smooth bromegrass had a r2 ranging from only 0.06 to 0.14 for the calibration equations regardless of the number of samples used. Near infrared reflectance spectroscopy was a rapid means of estimating leaf:stem ratios in monocultures of big bluestem and switchgrass but it was not suitable for smooth bromegrass.
    • Quality of forage stockpiled in Wisconsin

      Hedtcke, J. L.; Undersander, D. J.; Casler, M. D.; Combs, D. K. (Society for Range Management, 2002-01-01)
      Stockpiling forage is a commonly used method to extend the grazing season in the southern U.S.A. However, there is little data on stockpiled forage in the upper Midwest. This study was conducted to determine the quality changes of 7 stockpiled cool-season grasses [early and late maturing orchardgrass, Dactylis glomerata L., quackgrass, Elytrigia repens (L.) Desv. Ex. Nevski, reed canarygrass, Phalaris arundinacea L., smooth bromegrass, Bromus inermis Leyss., tall fescue, Festuca arundinacea Schreb., and timothy Phleum pratense L.], with and without N fertilizer, in Wisconsin. Forage was sampled at 3 offseason dates at 3 sites. To determine if N improved forage quality, 4 N-fertilizer treatments were imposed: 0 or 67 kg N ha(-1) applied at start of stockpiling and 2 treatments totaling 168 kg N ha(-1) applied in the fall and spring. Over winter, crude protein (CP) decreased from 116 to 107 g kg(-1), neutral detergent fiber (NDF) increased from 594 to 667 g kg(-1), acid detergent fiber (ADF) increased from 367 to 435 g kg(-1), and in vitro organic matter digestibility (IVOMD) fell from 734 to 655 g kg(-1). Nitrogen fertilizer improved CP in most environments but generally did not affect IVOMD, NDF, or ADF. Smooth bromegrass and quackgrass ranked highest in CP concentration and tall fescue ranked lowest. Timothy and late-maturing orchardgrass ranked highest in IVOMD while quackgrass and reed canarygrass consistently ranked lowest. Quality of all stockpiled forage studied can maintain livestock such as beef cattle or dry dairy cows over winter if the forage is accessible and adequate animal stocking density is maintained.
    • Technical note: Comparison of simulated ground nest types for grazing/trampling research

      Paine, L.; Undersander, D. J.; Sample, D. W.; Bartelt, G. A.; Schatteman, T. A. (Society for Range Management, 1997-05-01)
      Ornithologists often use simulated nests consisting of game bird or domestic poultry eggs to study nest survival. Researchers investigating cattle trampling of ground nests have sometimes used clay targets instead of actual eggs to avoid the confounding effects of nest depredation. To determine whether livestock respond similarly to clay targets and egg nests, we compared inadvertent trampling and intentional disturbance of clay targets versus clutches of 3 pheasant eggs by Angus X Holstein heifers. Overall trampling levels for clay target- and egg-nests were similar (35 and 36%, respectively). Cattle noticed and responded to both types of nests. When noticed, simulated nests were kicked, sniffed, licked, or picked up in the mouth. Cattle disturbed an average of 25% of the clay targets and 8% of the egg nests during 4 trials. Our results suggest that cattle are as likely to inadvertently trample egg nests as they are clay targets, but targets are more likely to attract attention and are therefore disturbed more often than egg nests. The greater likelihood of intentional disturbance of clay targets by cattle reduces the confidence of extrapolating the fate of this type of simulated nest to that of actual nests.