Huo, Y.L., & Li, G.W. 1990 [Investigations on decline and death of Pinus densiflora in the Yantai region, Shandong Province.. Forest Pest and Disease No. 3: 21-22.

Notes: The insect pest Matsucoccus matsumurae was formerly considered to be the direct causal agent which destroyed a great number of trees of P. densiflora in the Yantai region, Shandong Province, China. The results of this study, however, showed that canker disease caused by the fungus Cenangium abietis was the real direct causal agent, and that the damage caused by the pest caused decline of the trees and was only a disposition factor for the disease. Control of the disease and pest using cultural methods was tested.