Approximately 1,400 acres of spot burns (1 to 100 acres each) were created on a 3,000 acre chaparral area adjacent to the University of California, Hopland Field Station in southeastern Mendocino County and southwestern Lake County from 1963 through 1968 in order to observe the response of the resident deer (Odocoileus hemionus columbianus) population to brush burning. Observation of the deer population responses were continued through 1969. The vegetation on the study area consisted mainly of chamise (Adenostoma fasciculatum), live oak (Quercus wislizenii), scrub oak (Q. dumosa) 1 buckbrush (Ceanothus cuneatus), manzanita (Arctostaphylos spp.), and knobcone pine (Pinus attenuata). The health and productivity of the deer population on the study area were compared with those observed in deer on the lower part of the Hopland Field Station where the cover was primarily oak woodland with a grass understory and where burned brush was not available, by means of herd composition counts taken each April, July, and October. Body weights, rumen fill, blood urea nitrogen levels, and pregnancy rates were also determined in samples of deer collected from these two areas as well as from an unburned chaparral area approximately 2 miles east of the burn area. The plant species composition of rumen contents was also determined. Throughout the course of this study, the general health of deer on the burned chaparral area appeared better than that in the unburned chaparral but poorer than that observed on the Hopland Field Station. Year-to-year variations within each of the three areas studied was found to be as great as overall differences among habitat types. Although this burning program did not markedly improve the health and productivity of the deer population in the study area, such burning increases hunter access to deer in chaparral areas. This increased accessibility of deer for hunters may be equal in value to the forage improvement resulting from burning programs. An analysis of brush treatment costs, however, indicates that such management is economically questionable under current hunting regulations under which only adult males constituting 10 to 15% of the deer population are legal game. It is suggested that a major goal of chaparral management programs should be to increase the availability of grasses and forbs to deer for as much of the year as possible.
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