Graze on dry years let the system recover on wet years. Remember everything is interlinked. Removing a specific perennial may seem reasonable but it may be the link shunting water from the riparian or deeper rooted plants to the surrounding shrubs and trees. If a plant is too far off of the native community it will be rejected by it and not share with it. You've created competition where none needs to be.
Competition favors weeds.
Deep soil disturbance, including ditches, pipelines, roads, etc. Roads, with cuts or not, between a water source and vegetation shows plant stress or vegetation changes within 20-30 years in most of the arid sites. Most of our native soils have nutrients in parts per million. Native plants and their fungal partners cannot tolerate much fertility. Bacteria and weeds on the other hand love fertilizer.