Incidence of Phellinus robineae in Black Locust Plantings in Oklahoma. Jerry W. Riffle, Plant Pathologist, USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, Forestry Sciences Laboratory, University of Nebraska, Lincoln 68583. Alan K. Myatt, Area Forester, Oklahoma Forestry Division, Route 1, Box 44, Washington 73093; and Roger L. Davis, State Forester, State Department of Agriculture, Oklahoma Forestry Division, 2800 N. Lincoln Blvd., Oklahoma City 73105. Plant Dis. 69:116-118. Accepted for publication 20 September 1984. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1985. DOI: 10.1094/PD-69-116.

Incidence of sporocarps of Phellinus robineae on living black locust (Robinia pseudoacacia) in Oklahoma plantings was determined by examining about 15,000 trees in 144 plantings of six ages in five major land resource areas (MLRAs) from April 1981 to May 1982. Infected trees with sporocarps were found in 44% of the plantings and in 33 of 48 counties sampled. Incidence of infected trees among the MLRAs ranged from 0 to 7% and was significantly greater in the MLRA in western Oklahoma than in central and northeastern Oklahoma. Incidence of infected 10-yr-old trees was less than 1%; incidence increased significantly after trees were 15 yr old. More than 7% of 7,350 black locust trees 20, 24, 30, and 40 yr old in Oklahoma plantings in the five MLRAs had sporocarps.

Keyword(s): Phellinus punctatus, stem decay.