Size-density-age relationships in curlleaf mountain mahogany communities were studied in 25 study plots, each 30 × 30 m, in western and central Nevada. The influence of total vegetation cover (site potential) and relative mahogany cover (mahogany dominance) on the observed size-density-age relationships was investigated. A positive linear relationship was found between mean mahogany height and mean mahogany age. A positive nonlinear relationship was found between mean mahogany crown volume and mean mahogany age. Negative nonlinear relationships were found between mean mahogany density and mean mahogany age, and mean mahogany density and mean mahogany crown volume. Strong negative relationships were found between the mean combined density of established seedlings, juvenile, and immature mahogany and mean mahogany age and mean mahogany crown volume. Including total cover in the regression relationships between size, age, and density never increased the r2 value by more than .05. The addition of relative mahogany cover improved the r2 value for the relationship between mean mahogany density and mean mahogany crown volume by .28. The strong size-density and age-density relationships found indicate that intraspecific competition is probably occurring in the communities sampled, and that established seedlings, juvenile, and immature plants are the first individuals affected. Direct tests are needed to confirm these relationships.
Schultz, Brad W.; Tausch, R. J.; and Tueller, Paul T.
"Size, age, and density relationships to curlleaf mahogany (Cercocarpus ledifolus) populations in western and central Nevada: competitive implications,"
Great Basin Naturalist: Vol. 51
, Article 8.
Available at: http://scholarsarchive.byu.edu/gbn/vol51/iss2/8