Fencing small tree plantings, orchards, and gardens is effective in reducing porcupine damage. Electric fences are effective when the smooth electric wire is placed 1 1/2 inches (3.8 cm) above 18-inch-high (46-cm) poultry wire. A 4- to 6-inch (10- to 15-cm) electric fence can be enhanced by painting molasses on the wire. Porcupines will climb fences, but an overhanging wire strip around the top of the fence at a 65° angle to the upright wire will discourage them.
Completely enclose small trees with wire baskets, or encircle the trunks of fruit and ornamental trees with 30-inch (70-cm) bands of aluminum flashing to reduce damage.
Resources: (online)
Porcupine Control
