Journal of Range Management, Volume 39, Number 4 (July 1986)http://hdl.handle.net/10150/6355792024-03-28T19:42:25Z2024-03-28T19:42:25ZJournal of Range Management, Volume 39, Number 4 (July 1986)http://hdl.handle.net/10150/6504992020-12-23T01:08:19Z1986-07-01T00:00:00ZJournal of Range Management, Volume 39, Number 4 (July 1986)
Complete digitized issue.
1986-07-01T00:00:00ZWeather Factors Affecting 22 Years of Tallgrass Prairie Hay Production and QualityPowell, J.Stadler, S. J.Claypool, P. L.http://hdl.handle.net/10150/6454242020-09-25T02:47:36Z1986-07-01T00:00:00ZWeather Factors Affecting 22 Years of Tallgrass Prairie Hay Production and Quality
Powell, J.; Stadler, S. J.; Claypool, P. L.
Tallgrass prairie annual hay production and chemical composition (N, P, K, CA) data from a 23-year study conducted by H.J. Harper, Oklahoma State University, from 1929 through 1951 were correlated with corresponding monthly and seasonal temperature (mean, maximum and minimum, and absolute maximum and minimum), precipitation, wind, spring and fall growing season freeze dates, current and previous year's harvest dates, and previous year's yield. Multiple regression analyses were used to determine the weather variables and multiple regression equations which accounted for the greatest percentage of variation in annual hay production and nutrient concentrations. Equations with 4 independent weather variables for all months prior to the date of hay harvest produced high R2 values for production (82%), and N (80%), P (81%), K (81%) and CA (91%) concentrations. In general temperature values, especially in the fall of the previous year and January and mid-summer of the current year, accounted for more of the variation in all response variables than did any other kind of weather variable, such as precipitation, wind, or freeze date. Equations with 4 independent weather variables for those months prior to June produced only a moderate R2 value (48%) for production, but produced high R2 values for N (76%), P (74%), K (74%) and Ca (79%) concentrations. Relationships deserving additional research are suggested.
1986-07-01T00:00:00ZVelvet Mesquite Seedling Development in Three Southwestern SoilsBrock, J. H.http://hdl.handle.net/10150/6454212020-09-25T02:46:52Z1986-07-01T00:00:00ZVelvet Mesquite Seedling Development in Three Southwestern Soils
Brock, J. H.
Seedlings of velvet mesquite (Prosopis glandulosa var. velutina) were grown in sandy loam, clay loam, and clay soils to 30 and 60 days of age. Top and root growth parameters were measured at those time intervals and top growth was measured at 10-day intervals over the study period. A significantly (P=0.005) higher root growth rate and root penetration was found for seedlings in sandy loam and clay loam soils over the initial 30-day growth period. At approximately this time, top growth became favored over root growth. As a result, the rate of root growth in sandy and clay loam soils was reduced by nearly 60% during the second 30-day period. Seedlings grown in clay soils tended to have shorter root systems but the roots were more fibrous compared to seedlings in the other soils.
1986-07-01T00:00:00ZUtilization of White Locoweed (Oxytropis sericea Nutt.) by Range CattleRalphs, M. H.James, L. F.Pfister, J. A.http://hdl.handle.net/10150/6454152020-09-25T02:45:46Z1986-07-01T00:00:00ZUtilization of White Locoweed (Oxytropis sericea Nutt.) by Range Cattle
Ralphs, M. H.; James, L. F.; Pfister, J. A.
Utilization studies conducted on a high mountain range determined the quantity and timing of white locoweed (Oxytropis sericea Nutt.) consumption by cattle. Paired plots (one caged and one grazed) were clipped at the end of the grazing season to determine seasonal utilization. Biweekly visual appraisals were used to estimate percentage leaf grazed and number of reproductive stalks grazed and thus determine utilization patterns as the season progressed. Loco comprised 26% of the standing crop. Thirty-four percent of the available loco was utilized during the grazing season. Loco flower and pods (heads) were preferred to leaves. Utilization of loco heads increased linearly as the season progressed. Loco leaves were not consumed until the last 3 weeks of the grazing season. Loco heads also contained the highest concentration of the toxic alkaloid, swainsonine.
1986-07-01T00:00:00Z