Reuters: The area around Otjiwarongo in Namibia’s heartland is a green sea of short, shrubby trees as far as the eye can see. While beautiful to some, this bush is an invader species and seen by ranchers as a dreaded pest that pushes out nutritious grasses. Since the 1950s, bad grazing practices have led to the bush taking over 26 million hectares of Namibia’s rangeland – an area the size of New Zealand. That costs the country’s beef farmers $160 million a year in lost earnings, in an industry …