@proceedings {JRN55417,
	title = {Long-term effects of stocking rate, year, and weather on honey mesquite canopy cover and density},
	year = {2022},
	abstract = {Abiotic (precipitation, temperature) and biotic (grazing) factors are thought to be important drivers of undesirable woody shrub encroachment in arid rangelands. Woody encroachment has pervaded global rangelands over the past century, but the relative impacts of either grazing or climate are still not fully understood. We sought to evaluate the long-term (25 years; 1995-2019) effects of stocking rate (light: 25-30\% and conservative: 35-40\%; key forage species use rate), year, and the interaction of stocking rate by year to explore the impacts of grazing and annual weather fluctuations on percent cover and density of honey mesquite (Prosopis glandulosa), a native but invasive shrub, at the Chihuahuan Desert Rangeland Research Center (CDRRC) in southern New Mexico. Precipitation data were collected continuously at the CDRRC; temperature data were collected at the neighboring USDA-ARS Jornada Experimental Range. Drought occurred in 12 of 25 study years and mean ambient summer temperature increased from 15.1 {\textpm} 0.15 to 15.4 {\textpm} 0.27{\textdegree}C between the first and last 12 years of the study period. We found that stocking rate and the interaction of stocking rate by year had no effect on mesquite percent cover or density (\% cover: P = 0.70; density: P = 0.10), although year had a significant effect (\% cover: P < 0.01; density: P < 0.01). Mesquite canopy cover increased by 3\% from 3.8 to 7.1\% cover and mesquite density increased by 175\% (P < 0.01) from 284 {\textpm} 53 plants*ha to 782.08 {\textpm} 35 plants*ha between the last vs first three years of the study. Our preliminary results support a growing body of literature that suggests the overriding effects of climate (increased temperatures and prolonged droughts) will continue to drive undesirable shrub encroachment on Chihuahuan Desert rangelands even when animal stocking rates are kept at historically sustainable levels.},
	keywords = {and density, canopy cover, honey mesquite, Long-term effects, stocking rate, weather, year},
	author = {Matthew M. McIntosh and Jerry L. Holechek and S. Spiegal and Andr{\'e}s F. Cibils and Richard E. Estell and Caitriana Steele and Jeon, S. and Brandon T Bestelmeyer}
}
@unpublished {JRN54835,
	title = {Range ewe production under twice a year lambing. II. Lamb and wool production},
	year = {1978},
	abstract = {<p>The practice of twice a year lambing offers increased opportunities for the sheep industry to expand production. The reproductive rate of sheep is determined by prolificacy and the frequency of lambing. Several experiments to breed ewes twice yearly have been reported involving many breeds of sheep (Land and McClelland, 1971; Copenhaver and Carter, 1972; Whiteman <u>et al</u>., 1972; Walton and Robertson, 1974; and Speedy <u>et al</u>., 1976). In these studies flock numbers were small and the sheep were generally managed under farm flock conditions.</p>

<p>The purpose of this study was to attempt to successfully breed and lamb certain genotypes of sheep twice-a-year under modified range conditions.</p>
},
	keywords = {Lamb and wool production, lambing, Range ewe production, year},
	author = {L. G. McNeal and Clarence V. Hulet and J. L. Walters and W.C. Foote}
}
