Plant and mammal changes on a clearcut in west-central Oregon

Plant composition and coverage and small mammal populations were comparedin virgin forest (control) and clearcut (experimental) areas from April 1954 to October 1965.Changes in ground cover vegetation were modest on the control area but marked on theexperimental area. A late fall burn on the experimental area may have retarded herbaceousplant establishment. Nearly half of the herbaceous species were invaders not found in thevirgin Douglas-fir (Pseudotsuga menziesii) forest. Ground plant coverage was less than 23%in the virgin forest ; 1 year after the clearcut area was burned, the cover was 2%; and by 10years it was above 53%. Woody plant coverage (mostly sprouts) was slightly more abundantthe first 2 years after burning. Herbaceous species then became dominant for a 3-year period,after which woody plants gradually gained dominance.
Deer mice (Peromyscus maniculatus) increased on the experimental area soon after theburn. The populations varied from an estimated 0.9 to 12.8 animals per acre and fluctuatedwidely and irregularly. Townsend's chipmunk (Eutamias townsendii), Oregon vole (Microtusoregoni), and snowshoe hare (Lepus americanus) populations also increased on the area atdifferent periods after the burn. Trowbridge's shrews (Sorex trowbridgii), vagrant shrews(Sorex vagrans), and ermine (Mustela erminea) were present on both areas in relativelylow numbers. Redback voles (Clethrionomys occidentalis), Douglas' squirrels (Tamiasciurusdouglasii), and northern flying, squirrels (Glauconzys sabrinus) were not found on the clearcut.California ground squirrels (Spermophilus beecheyi) migrated to the clearcut and establisheda modest population. Richardson's voles (Microtus richardsoni), jumping mice (Zapus trino-tatus), bushy-tailed woodrats (Areotoma cinerea), and a pika (Ochotona princeps) werevisitors.