This recycling causes the reuse of any nutrient consumed. At each deposit more forage grows, fewer numbers of weed herbage emerge, and the weeds are more palatable, causing more weed use and greater other forage production. Nutrient recycling goes on indefinitely. Higher stock densities cause increased browsing of broadleaf weeds, more physical abuse by trampling and lower weed populations. This happens in both fertilized and non-fertilized situations.
Most weeds are either preferred or acceptable to grazing beef cattle.
Relatively few weeds are useless as livestock feed. In this situation we might consider the analogy that fencing functions as a sprayer and the livestock are, in effect, the herbicide or mowing equipment. Higher stock densities result in excellent woody plant, small sprout, bush or tree control through browsing since physical impact results in less woody plants. In many paddocks, these plants are kept at a low level through stock impact. There have been cases when aphids, army worms, or leaf diseases infested certain paddocks and were controlled through grazing and trampling at high stock densities, thus illuminating the need for chemical controls if that were an option.