Globally, grasslands are under threat from woody encroachment by invasive alien plants and this undermines grass production. The study sought to determine the effects of Acacia mearnsii clearing on soil physico-chemical properties and grass production. Soil samples were collected from three A. mearnsii invasion statuses and analysed for representative physico-chemical variables. Using line transects and a disc pasture meter (DPM) approaches, equations were developed to predict annual grass dry matter production in areas cleared of A. mearnsii. A. mearnsii significantly (p < 0.05) altered most of the physico-chemical soil characteristics that affected grass production. Predicted grass dry matter production from sites cleared of A. mearnsii ranged from 284 to 362 g m⁻² y⁻¹. These production rates were similar to those from uninvaded landscapes, suggesting that background grass production can still be attained even if there is no active soil management. Autogenic recovery thresholds have not been surpassed despite a long history of landscape invasion in the area. Management of invaded grasslands should be informed by an appreciation of local soil background characteristics. The equations developed for grass dry matter prediction may enable farmers to non-destructively estimate forage availability and fuel loads.

在全球范围内，草原正受到外来入侵植物木本侵占的威胁，这破坏了草的生产。该研究旨在确定金合欢清除对土壤理化特性和草产量的影响。从三个A. mearnsii入侵状态收集土壤样品，并分析具有代表性的物理化学变量。使用线断面和圆盘牧草仪 (DPM) 方法，开发了公式来预测在清除了A. mearnsii 的地区的年度草干物质产量。A. mearnsii显着 ( p < 0.05) 改变了影响草产量的大部分土壤理化特性。来自清除场地的预测草干物质产量A. mearnsii 的范围为 284 至 362 gm ^-2 y ^-1。这些生产率与未入侵景观的生产率相似，这表明即使没有积极的土壤管理，仍然可以实现背景草的生产。尽管该地区的景观入侵历史悠久，但尚未超过自生恢复阈值。入侵草原的管理应通过了解当地土壤背景特征来了解。为草干物质预测开发的方程可以使农民能够无损地估计草料可用性和燃料负荷。