Relative Susceptibility to Cronartium Ribicola of 5-Needled Pines Planted in the East

Forest pathologists have worked many years to determine the relative susceptibility to blister rust of various species of native and exotic 5-needled pines. This paper deals with the relative susceptibility of eleven species of such pines growing under natural environmental conditionsprevailing in the Adirondacks and in central New York State. Pinus cembra var. helvetica appeared to be resistant. Pinus monticola and P. flexilis were more susceptible than P. strobus ; and P. strobiformis , P. peuce , P. koraiensis , and P. aristata were less so in the order named. In generalthese results substantiate the earlier work of Dr. P. Spaulding.