Possums ignore old leaves and select the best new growth. In some areas they have eaten whole canopies of rata, totara, titoki, kowhai and kohekohe. Possums compete with native birds for habitat and for food such as insects and berries. They also disturb nesting birds, eat their eggs and chicks and may impact on native land snails. Dairy and deer farmers have the added worry of possums spreading bovine tuberculosis.
Possums are a nuisance in suburban gardens, and sometimes even indoors.
Individual trees can be protected with metal strips placed about a metre above ground level, as seen on telephone poles, to stop possums from climbing up. Allow to set, then spread on the base of the tree. Stir well and apply 20 ml per tree after planting. Bait stations are widely used by possum control agencies to give sustained control of possum populations, with minimal risk to humans, pets or livestock. A wide range of baits and bait stations are now available.