Pini Rot

Phellinus pini (Thore:Fr.) Pilat.

From: Field Guide to Diseases and Insect Pests of Idaho and Montana Forests, USDA Forest Service Northern Region, Publication Number R1-89-54

Hosts. – Douglas-fir, western larch, Engelmann spruce, and pines are the most common hosts, although it is reported to infect all conifers in Idaho and Montana.

Distribution. – Range of hosts in Idaho and Montana.

Damage. – Heartrot of stem. Decay generally extends 2 to 3 feet above and 3 to 5 feet below each conk or punk knot. Presence of several conks or punk knots indicates complete cull.

Identification. – Conks are woody with a dark, ridged upper surface and a tan pore layer on the underside (fig. 10). They range from hoof-shaped to appressed to the bark with little or no upper surface (resupinate). They are usually 2-4 inches in diameter. The context is tan or brown. Punk knots are filled with brown mycelium (figs. 11, 12). The rot first appears as a red or brown stain in the heartwood. The stain often forms concentric rings or crescents in cross section. In later stages, white pockets are distinct from the surrounding dark red or brown wood (fig. 13).

	Image Unavailable
Figure 10. - Pini Rot fungus fruits on the bark of infected trees. The conks are woody with a cinnamon-colored pore layer on the lower surface.	Figure 11. - Pini Rot is often indicated by swollen knots on the stem which have a brown, punky interior.
Image Unavailable	Image Unavailable
Figure 12. - Punk knots on the stem of a tree with Pini Rot.	Figure 13. - Pini Rot has solid, brown wood between pockets.

Similar damages. – In true firs or hemlock, Echinodontium tinctorium also causes a common heartrot.

Link to Table 1 – Comparison of Common Heartrots in Species Other Than Western Redcedar

Link to Images in Forestry Images

References.

Anonymous. 1982. For. Insect & disease identification and management. USDA For. Serv., Northern Region; Idaho Dept. of Lands, Insect and Disease Control; Montana Dept. of State Lands, Division of Forestry. 192 p.

Bega, R. V. 1978. Diseases of Pacific Coast conifers. USDA For. Serv. Ag. Hndbk. No. 521, 206 p.

Boyce, J. S. 1961. Forest Pathology. McGraw-Hill Book Co., New York, NY. 572 p.

Hepting, G. E. 1971. Diseases of forest and shade trees of the United States. USDA For. Serv. Ag. Hndbk. No. 386, 658 p.

Kimmey, J. W. 1964. Heartrots of western hemlock.  USDA For. Serv., For. Pest Leaflet 90, 7 p.

[  Back  ]