In mixed C₃/C₄ grasslands of the southern Great Plains of North America, honey mesquite (Prosopis glandulosa Torr.) invasion facilitates the dominance of the C₃ midgrass Texas wintergrass (Nassella leucotricha [Trin. & Rupr.] Pohl) to the detriment of warm-season grasses. Little is known about the viability of targeted grazing as a treatment method for reducing Texas wintergrass biomass and reproduction, particularly under mesquite canopies. We quantified the effects of targeted grazing treatments (grazed once [G1], grazed twice [G2], and control) and mesquite canopy position (under canopy [UC] and outside of canopy [OC]) on Texas wintergrass basal area, total dry matter (DMY) per basal area, live DMY per basal area, dead DMY per basal area, leaf length, total number of reproductive culms per plant, number of fungus-infected reproductive culms per plant, and rate of reproductive culm development over 2 yr at two study sites. Targeted grazing reduced leaf length and biomass and slowed reproductive development of the wintergrass plants that cattle could more easily access. Environmental factors and differences in mesquite physiognomy at the two study sites likely interacted with grazing treatments, making it challenging to separate the impacts of targeted grazing treatments from other factors. Results suggest mesquite removal is likely necessary to increase cattle access to Texas wintergrass, particularly in stands with multistemmed trees.

在北美大平原南部的C ₃ /C _{4混合草原中，蜜豆灌木 (} Prosopis mudulosa Torr.) 的入侵促进了 C ₃中草德克萨斯冬草 ( Nassella leucotricha ) 的统治地位[特林。& Rupr.] Pohl）不利于暖季草。人们对定向放牧作为减少德克萨斯冬草生物量和繁殖的处理方法的可行性知之甚少，特别是在豆科灌木树冠下。我们量化了针对性放牧处理（放牧一次 [G1]、放牧两次 [G2] 和对照）和豆科灌木冠层位置（冠层下 [UC] 和冠层外 [OC]）对德克萨斯冬草断面积、总干度的影响。每断面积的物质 (DMY)、每断面积的活 DMY、每断面积的死 DMY、叶长、每株植物的生殖秆总数、每株植物受真菌感染的生殖秆数以及 2 年以上生殖秆发育率在两个研究地点。有针对性的放牧减少了叶子的长度和生物量，并减缓了牛更容易接触到的冬草植物的繁殖发育。两个研究地点的环境因素和豆科灌木的地貌差异可能与放牧处理相互作用，因此很难将有针对性的放牧处理与其他因素的影响分开。结果表明，为了增加牛接触德克萨斯冬草的机会，可能有必要清除豆科灌木，特别是在多茎树木的林地。