Woody plant encroachment into rangeland ecosystems is a widespread and often unwelcomed circumstance affecting rangeland management decisions worldwide. In the rangeland management profession, varying philosophies have been employed in the management of woody plant encroachment. Following World War II, total eradication of woody plant cover was commonly practiced, eventually giving way to a mosaic approach that benefits livestock, wildlife, and recreational objectives, with cover increasing or even stabilizing in many areas. Cultural practices such as land fragmentation, lifestyles not dependent on agricultural income, and shifts in herbivory from predominately browsers to grazers may also be contributing factors. Modern image analysis technologies, such as object-oriented feature extraction and patch metric analyses, can shed light on past paradigm shifts through spectral and textural assessment of modern and historical aerial photography. In this study, woody plant cover and patch metrics were analyzed for a period spanning from 1938 to 1940 through 2018 in the Bennett and Sulphur Creek watersheds of the Lampasas Cut Plain of Central Texas. Object-based feature extraction was used to calculate woody plant cover, and Fragstats was used for landscape patch metrics. Total woody cover was compared with past stewardship paradigms. There was a net decrease of total woody plant cover from 1938 to 1940 through 2018, with variation in between as management paradigms shifted. A pattern of decline, regrowth, and stabilization, like that observed in other research, was noticed for the Bennett Creek watersheds but was not apparent in Sulfur Creek. Patch size/shape varied as well, but fractal patch complexity was relatively stable through time. Raster algebra analysis showed that < 10% of the initial woody cover from 1938 to 1940 remained in 2018, although total cover went through various expansion/reduction phases. This research underscores the importance of long-term datasets and locally based knowledge in the application and interpretation of historical management paradigms.

木本植物侵占牧场生态系统是一种普遍且通常不受欢迎的情况，影响着全球牧场管理决策。在牧场管理专业中，木本植物侵占的管理采用了不同的理念。第二次世界大战后，普遍实行了彻底根除木本植物覆盖的做法，最终让位于有利于牲畜、野生动物和娱乐目标的镶嵌方法，许多地区的覆盖增加甚至稳定。土地分割、不依赖农业收入的生活方式以及食草动物从主要食肉动物转向食草动物等文化习俗也可能是促成因素。现代图像分析技术，例如面向对象的特征提取和补丁度量分析，可以通过现代和历史航空摄影的光谱和纹理评估来揭示过去的范式转变。在这项研究中，我们分析了 1938 年到 1940 年到 2018 年在德克萨斯州中部兰帕萨斯切割平原的 Bennett 和 Sulfur Creek 流域的木本植物覆盖和斑块指标。基于对象的特征提取用于计算木本植物覆盖率，Fragstats 用于景观斑块度量。将总木质覆盖与过去的管理模式进行比较。从 1938 年到 1940 年到 2018 年，木本植物总覆盖率净减少，随着管理范式的转变，两者之间存在差异。Bennett Creek 流域出现了衰退、再生和稳定的模式，就像在其他研究中观察到的那样，但在 Sulphur Creek 中并不明显。补丁大小/形状也各不相同，但分形补丁复杂性随着时间的推移相对稳定。栅格代数分析表明，1938 年至 1940 年的初始木质覆盖率的 < 10% 保留在 2018 年，尽管总覆盖率经历了不同的扩展/减少阶段。这项研究强调了长期数据集和基于本地的知识在历史管理范式的应用和解释中的重要性。