These plantings were initially spineless and showed little tendency to spread. However, within a few years some trees reverted to wild types with spines and weedy tendencies. Mesquite trees were initially hard to establish, but spread rapidly after a series of wet years. They have continued to spread in favourable seasons, but do not reduce in area during drought. They now infest many square kilometres of valuable river-front grazing land, especially in the Pilbara region of W.A. and other parts of the Australian tropics.
Honey mesquite is a native of Texas, New Mexico and Arizona rangelands.
It has become a major weed there due to grazing by cattle, which remove competing plants and leave mesquite largely undamaged. Control of prairie fires may also have favoured mesquite at the expense of other plants. Other species originate from South America. In many third world countries it is valued for fuel wood and the edible pods which are gathered by hand. Mesquite is an aggressive invader of rangeland.