Barbara and Neill Simpson with Loder Cup
Among many other successes, the Simpsons were central to the reforestation project on the Lake Wakatipu islands from 2000, planting more than 40,000 native plants there.
Mr Simpson, a former DOC ranger, is an acknowledged expert on native plants and the effects of exotic pests on their ecosystem, while Mrs Simpson has introduced hundreds, if not thousands, of children to our natural world through successful school and community volunteer programmes.
The Simpsons were presented with the cup at the 2016 Green Ribbon Awards.