Basal Fire Scars and the Occurrence of Decay in Lodgepole Pine

Abstract

An examination of lodgepole pines with basal fire scars has shown a correlation between the incidence of fungi entering the scars and the area of the scars. A number of fungi entering the scars and associated with red stain, other decays, and blue stain, are identified and illustrated. The significance of fire scars in the management of lodgepole pine in Alberta is discussed.

Decay of Lodgepole Pine in Two Foothills Sections of the Boreal Forest in Alberta

“…The present results confirm earlier low estimates for Alberta (Nordin, 1958), and correspond to similarly low decay losses for jack pine in Ontario (Basham, 1958).…”

“…The identities of the principal fungi isolated from heartwood stains and decays of lodgepole pine in Alberta were established in earlier investigations (Nordin, Sutton and Heming, 1953;Nordin and Carm,ichael, 1957;and Nordin, 1958). The present study was intended to supply additional information on the decay relationships for the species.…”

A Model of Fire Selection for Serotiny in Lodgepole Pine

“…Low-intensity fires often thin a stand and allow a second generation (sometimes a third) to be established by seed from remaining open-cone trees (Brown, 1975). Trees that survive a ground fire will likely be scarred and susceptible to infection by fungal pathogens (Nordin, 1958). Their eventual death will add a large amount of fuel to the system, increasing the probability of a holocaust (d. Gara et al, in press).…”

The Origin of Basal Scars in the British Columbia Interior White Pine Type

“…Any injury which kills sapwood may provide an entrance court for decay-producing fungi. However, investigations on various species have shown that different amounts of decay are usually correlated with different types of scarring (3,4,6,11,12,13). Parker (12), for example, found that locality, species, and diameter of the affected tree, and scar size (area), depth, position, and age were all factors in the incidence of infection and decay development.…”

“…Both fire and mechanical injury scars are known to be associated with decay. Since scars resulting from ground fires usually contact the ground, infection almost invariably follows ( 11,12). Ground-contact logging scars likewise are reported to be very susceptible (12).…”