Little Response of True Fir Saplings to Understory Shrub Removal

The ability of white fir and California red fir to become established, persist, and eventually dominate montane shrub fields is well known. When the firs have eventually dominated do the understory shrubs continue to inhibit growth? In a small study in the southern Cascade Range of northeastern California, we tested the growth response of a thinned stand of saplings to removal of a shrub understory. Also, we examined several commonly used predictors of the ability of saplings to respond to release. Results indicated a statistically significant increase in dbh and height growth following release that disappeared after 5 yr. The growth response that was probably too small to justify the cost of shrub removal was best predicted by the trees' height growth the 5 yr before release. West. J. Appl. For. 17(1):5–8.