Delineation of fusiform rust hazard based on estimated volume loss as a guide to rust management decisions in slash pine plantations
Schmidt, R.A.; Klapproth, M.C.
Southern Journal of Applied Forestry 6(1): 59-63
Using published data, an empirical model was derived to approximate volume loss due to fusiform rust [Cronartium quercuum f. sp. fusiforme] in slash pine plantations. Cumulative percentage volume loss at age 15 yr is estimated as a function of percentage-rust-associated mortality at age 15 yr, percentage stems infected at age 5 yr and percentage trees infected at ages 5-10 yr. Volume losses of < 15%, 15-35% and > 35% at age 15 yr are arbitrarily defined as low-, moderate- and high-rust hazard, respectively. The corresponding percentages of trees with rust were < 18%, 18-43% and > 43% at age 5 yr and < 44%, 44-77% and > 77% at age 10 yr. Using these approximations, a regional rust-hazard map for 10-yr-old slash pine plantations is developed from rust survey data and potential rust management strategies are discussed for the region and for plantations.