Oak regeneration ecology
During the summer of 2009 Rodolfo Dirzo began a long term study of the impact of herbivory by large mammals, principally deer and rabbits, on 3 oak species. For the study, Rodolfo identified 75 pairs of oak seedlings for each of 3 species: Quercus agrifolia, Q.lobata, and Q. douglasii. Each pair was chosen to be similar in size and located close to each other, usually 2 meters or less apart. Pairs were chosen that had approximately the same height, the same number of stems, the same number of branches, and the same number of leaves. One of each pair is enclosed in a circular wire cage about 1 meter high to protect it from herbivory. The other member of the pair has no cage and is identified by plastic spikes in the ground near it. Its location in distance and direction from the enclosed member of the pair was recorded.
Some of the cages for this experiment are visible along the Fire Road and in the grassy drainage below the road Y as you leave the visitor parking lot.
Rodolfo plans to assess each pair once a year for survival and performance over a period of at least 10 years. During this period he also plans additional assessments of acorn germination and planted seedling success in some of the paired specimen locations.