Services biologist, California Department of Food and Agriculture, Redding, Calif
Pages: 5 Published: Jun 1979
Four exclusion cylinder designs were tested to determine the impact of a cylinder enclosure on the production of the enclosed alfalfa. The designs of the 1.07-m (42-in.) diameter cylinders can be described as follows: (a) 0.9-m (3 ft) high, 25.4-mm (1-in.) mesh welded wire with open top; (b) 0.9-m (3-ft) high, 25.4-mm (1-in.) mesh welded wile with 25.4-mm (1-in.) mesh top; (c) 0.9-m (3-ft) high, 6.35- mm (0.25-in.) mesh hardware cloth with open top; and (d) 0.46-m (18-in.) high, 25.4-mm (1-in.) mesh welded wire with 25.4-mm (1-in.) mesh top. The cylinders were placed in ground-squirrel-free alfalfa fields for various time intervals from mid-March to mid-June 1976 and 1977. The sample unit included vegetation within a cylinder and comparable area(s) of vegetation within 1.5 to 3m (5 to 10 ft) from each cylinder, each clipped at ground level. Dry weights were taken of each sample to estimate the hay production. None of the cylinder designs except the 6.35-mm (0.25-in.) mesh caused significant growth change in the enclosed alfalfa. This design resulted in a 15 percent reduction in forage production. No significant small herbivore population was determined by visual observation or feeding activity at feeding census stations.
vertebrate pest control, exclusion cylinders, damage assessment, rodent damage
Paper ID: STP34966S