A JFSP Fire Science Exchange Network
Bringing People Together & Sharing Knowledge in the Northern Rockies

Influence of fire on mycorrhizal colonization of planted and natural whitebark pine seedlings: ecology and management implications

Author(s): Paul E. Trusty, Cathy L. Cripps
Year Published: 2011

Whitebark pine (Pinus albicaulis) is a threatened keystone species in subalpine zones of Western North America that plays a role in watershed dynamics and maintenance of high elevation biodiversity (Schwandt, 2006). Whitebark pine has experienced significant mortality due to white pine blister rust, mountain pine beetle outbreaks and successional replacement possibly due to fire suppression (Schwandt 2006; Smith and others 2008). Current management strategies include letting lightning fires burn or applying prescribed fire to provide habitat for natural seedling establishment or the planting of rust resistant seedlings (Keane and Parsons 2010a, 2010b). However survival rates after fire are variable and can be low (Izlar 2007; Keane and Parsons 2010a; Perkins 2004; Tomback and others 2001). All pines in nature require ectomycorrhizal (ECM) fungi for establishment, growth, health and sustainability (Read, 1998). ECM fungi enhance nutrient uptake and offer protection against drought, pathogens, soil grazers and heavy metals (Smith and Read 1997). Fire can affect ECM communities in soil but impacts are unpredictable and depend on the intensity of the fire, forest type and other factors (Cairney and Bastias 2007). Intense fire has the potential to detrimentally impact ECM communities because of the deep penetration of lethal soil temperatures, the complete loss of the original tree host, and changes in abiotic conditions, including an increase soil surface temperature (Neary and others 1999; Wiensczyk and others 2002). When tree hosts are lost or removed, studies show that ECM fungal viability in the soil declines rapidly after two or three years (Haggerman and others, 1999) and recovery of ECM communities from burning and cutting can take decades (Visser 1995). It is unknown how long ECM fungi, and particularly those specific to whitebark pine, can remain in the soil of ghost forests without presence of a living host. Fire is historically linked to whitebark pine ecology (Keane and Arno 1993). Fire has the potential to reduce shade-tolerant understory species such as fir; remove canopy for shade-intolerant whitebark pine seedlings; provide openings for nutcrackers to plant seed; reduce rust and beetle infested older trees, and facilitate plantings of rust resistant seedlings (Keane and Parsons 2010a). However, little is known of how fire affects the beneficial fungi on roots of this tree species. This study evaluated the impact of fire on the mycorrhizal communities on planted and naturally occurring whitebark pine seedlings from an ecological perspective and to address management concerns.

Citation: Trusty, Paul E.; Cripps, Cathy L. 2011. Influence of fire on mycorrhizal colonization of planted and natural whitebark pine seedlings: ecology and management implications. In: Keane, Robert E.; Tomback, Diana F.; Murray, Michael P.; and Smith, Cyndi M., eds. 2011. The future of high-elevation, five-needle white pines in western North America: Proceedings of the High Five Symposium; 2010 June 28-30; Missoula, MT. Proceedings RMRS-P-63. Fort Collins, CO: USDA Forest Service, Rocky Mountain Research Station. p. 198-202.
Topic(s): Fire Effects, Ecological - First Order, Ecological - Second Order, Soils, Vegetation, Fire Regime, Fire Intensity / Burn Severity
Ecosystem(s): Alpine forest/krummholz, Subalpine wet spruce-fir forest, Subalpine dry spruce-fir forest
Document Type: Conference Proceedings
NRFSN number: 11898
FRAMES RCS number: 13783
Record updated: Oct 3, 2019