Grazing and Grazing Exclusion Effects on New Mexico Shortgrass Prairie

Abstract

Vegetative differences and changes were evaluated over a 6-year period (1999-2004) on adjoining conservatively grazed and grazing-excluded (22 years) shortgrass rangelands in northwestern New Mexico. Autumn total perennial grass and blue grama (Bouteloua gracilis [Willd. ex Kunth] Lag. Griffiths) standing crop did not differ on grazed and grazing-excluded areas when data were averaged across years. There were no long-term differences in vegetation basal cover or composition between the grazed and grazing-excluded areas. Plant community similarity values between the grazed and grazing-excluded areas were 80% and 93% during the first 2 years (1999-2000) and last 2 years (2003-2004) of study, respectively. Climatic conditions had more impact on vegetation composition of the 2 areas than livestock grazing. Similarity values between 1999-2000 and 2003-2004 periods were 52% and 64% for the grazed and grazing-excluded plant communities, respectively. At the beginning of our study, blue grama productivity was depressed on the grazed area compared to the exclosure, but after 3 years of conservative winter grazing, it was similar on the 2 areas. Our study indicates there is no benefit to blue grama rangelands from long-term rest from the standpoint of vegetation composition. Resumen Las diferencias vegetativas y sus cambios se evaluaron por un periodo de seis añ os (1999-2004) en dos pastizales de zacates cortos adjuntos y ubicados en el noroeste de New Mexico, uno de ellos apacentado conservativamente y el otro excluido al apacentamiento (22 añ os). La biomasa total de zacates perennes y de ''Blue grama'' (Bouteloua gracilis [Willd. ex Kunth] Lag. Griffiths) en otoñ o, promediada a través de los añ os, no difirió entre las á reas apacentada y excluida. No hubo diferencias a largo plazo en términos de cobertura basal de la vegetació n o su composició n entre las dos á reas evaluadas. Los valores de similaridad de la comunidad vegetal entre las á reas apacentada y excluida fueron 80% y 93% durante los primeros dos añ os (1999-2000) y los dos ú ltimos (2003-2004) del estudio respectivamente. Las condiciones climá ticas tuvieron má s impacto sobre la composició n de la vegetació n de las dos áreas que el apacentamiento. Los valores de similaridad entre los periodos de 1999-2000 y 2003-2004 fueron 52% y 64% para las comunidades vegetales apacentada y excluida, respectivamente. Al inicio de nuestro estudio la productividad del ''Blue grama'' disminuyó en el á rea apacentada en comparació n con la excluida, pero después de tres añ os de apacentamiento conservativo en invierno fue similar en las dos á reas. Nuestro estudio indica que, desde el punto de vista de la composició n de la vegetació n, no hay beneficio para el ''Blue grama'' por el descanso de largo plazo.

Grazing Exclusion Changed the Complexity and Keystone Species of Alpine Meadows on the Qinghai-Tibetan Plateau

“…We found that the structure of the plant community was different among GE5, GE7, and continuous grazing plots, but it was similar between GEO7 plots and continuous grazing plots. This phenomenon was consistent with experimental results obtained from a New Mexico short-grass prairie (Holechek et al, 2006). Stable species richness and similar complexity level mean a similar competition situation in plant communities, which might be the reason why the plant community was similar between long-term grazing exclusion and continuous grazing pastures in GEB5, Grazing exclusion below 5 years; GE5, Grazing exclusion 5 years; GE7, Grazing exclusion 7 years; GEO7, Grazing exclusion over 7 years; TN, Total nitrogen; AN, available nitrogen; TOC, total organic carbon; AP, available phosphorus; AK, available potassium; BD, bulk density.…”

Grazing moderates increases in C3 grass abundance over seven decades across a soil texture gradient in shortgrass steppe

“…; Holechek et al. ). Five decades of grazing exclusion in shortgrass steppe induced only modest community shifts (Milchunas et al.…”

“…; Holechek et al. ). After 23 yr of implementing grazing intensities that varied from light to heavy, Hyder et al.…”

A Comparison of Native Grass and Triticale Pastures during Late Winter for Growing Cattle in Semiarid, Subtropical Regions

“…Differences between 2013, 2014, and 2016 in initial body weights are likely due to a consistent single source with a limited spring calving period in the first two years, compared to sale barn cattle from multiple unknown origins in the third year. Range pastures were unequally sized, ranging from 5 to 16 ha across years; consequently, various numbers of animals were assigned to those pastures to provide for up to 50% utilization, as a moderate grazing intensity [14,15], during the anticipated grazing season to end in mid-March (30 d Every year, immediately prior to grazing, a sample was hand-clipped to ground level from a 0.5 m 2 area in each of three visibly representative areas in each pasture [5], and dried in a forced-air oven at 60 • C for 48 h [5]. These samples were submitted for estimation of CP and fiber-based components by near-infrared spectroscopy (NIRS) at Ward Laboratory (Kearney, NE, USA) using a calibration developed for grass hay by the NIRS Consortium (https://www.nirsconsortium.org/; accessed on 11 June 2021).…”

“…There was no difference between pastures in forage mass again in 2016 (Table 3). Weather data for 2014-15 are included in Table 2 to show at least a temporary alleviation of the drought in 2015 to promote native grass growth for grazing in late winter 2015-2016 (Table 3) [14,15,23]. Much earlier planting of triticale, coupled with greater precipitation (Table 2), led to greater forage mass in those pastures as well.…”