Reducing Muskrat Damage to Plants: An Integrated Pest Management Approach

R. DeGregorio
Parsons Brinckerhoff, Inc., Central Artery/Tunnel

C. Meiniger
Bechtel Corp., Central Artery/Tunnel

T. Swift and J. Dolan
Massachusetts Turnpike Authority, Central Artery/Tunnel

 

Delivered at 2003 Boston Harbor Islands Science Symposium.

---

After clearing and grubbing, over 3.5 million cubic yards of Central Artery/Tunnel excavate was placed on Spectacle Island and its landfill capped. Permanent seeding began in 1995; planting was completed by early spring 2000. About 3,000 trees and over 26,000 shrubs and vines were planted. Low turf & meadow grass mixtures were seeded as were mixes in shrub beds and around trees.

In autumn 1997 some muskrat damage to a small number of black cherry (Prunus serotina) was observed. Increasingly, woody plantings were damaged up to 18 inches (45 cm) above ground in the absence of snow, often in association with muskrat scat. Vole/rabbit signs, however, were not found. Shooting and an effort to live trap began in early 2000. Tree guard installation began in early 2001. This poster contrasts different types of trees as being more or less susceptible to muskrats: smooth vs. rough bark; deciduous vs. needle evergreen; few vs. many lower branches; single vs. multistem; larger vs. smaller caliper; and Rosaceae vs. other families, respectively. This approach can help managers identify present species needing tree guards and future species unlikely to be damaged. The integrated pest management (IPM) program is also illustrated. Muskrat is reported in the literature to exhibit food preferences, to have reduced marshes to mud in the North and South, and to alter succession. Muskrats can reduce biodiversity within the Boston Harbor islands.