Sheep Camps: before we bought Yallaroo the property was heavily grazed by sheep. Large sheep numbers were accommodated on Yallaroo. Sheep rest at night in areas where they feel secure. These areas are known as sheep camps. A large sheep camp was situated on the highest point on Yallaroo, which was where we decided to place our home.
Over a period of time, the fertility of sheep camps increases dramatically due to the liquid and solid output of the sheep. This nutrient build-up causes a proliferation of weeds on sheep camps. Even when sheep are removed the results of their fertilisation are evident for many years. Our sheep camp was the home to a bewildering collection of noxious and obnoxious weeds. Included in this botanical rogue’s gallery were Horehound (Marrubium vulgare), Stinging Nettle (Urtica incisa) and various thistles.
A number of strategies were adopted to eradicate weeds. Some of these strategies were accomplished more by good luck than management. We have been mowing a large area near the house for many years. This was basically to create a firebreak. An unexpected result of mowing was the victual disappearance of weeds and their replacements by more acceptable native herbs and grasses.
Where we established gardens, glyphosate herbicide was used to knock down the weeds. We now use sheets of corrugated iron on areas to be cultivated. The iron acts as an organic herbicide. After four or five weeks, the ground under the iron is devoid of weeds and ready for planting. The iron sheets starve the weeds of light and also burn the weeds as the iron heats up during the day.
In garden beds remnant sheep camp weeds disappear because mulch inhibits weed growth.  Also the density of cultivated plants eventually shades the ground and put a brake on weed growth.

Research