Date of this Version
An increase in the use of plastic tubing systems to collect sap from sugar maples (Acer saccharum) has allowed syrup producers to boost production in recent years, but not without cost. Rodents gnawing on tubing, spouts, and fittings may cause damage in excess of $300,000 annually in Vermont, the largest maple producing state. Red squirrels (Tamiasciurus hudsonicus), gray squirrels (Sciurus carolinensis), and chipmunks (Tamias striatus) appear to be responsible for the majority of damage. Other species including flying squirrels (Glaucomvs sabrinus) , white-footed mice (Peromvscus leucopus), porcupines (Erethizon dorsatum), and woodpeckers (Picidae spp.) may also cause substantial damage. Past attempts to control damage with zinc phosphide treated grain, shooting, and trapping have been costly, labor intensive, and generally unsuccessful. Control techniques including habitat manipulation, repellents and exclusion with electric polywire are being field tested. Mast crops are being monitored in an attempt to predict changes in rodent populations, and tooth mark patterns on tubing are being studied so that the species responsible for the damage can be properly identified.