• IMMEDIATE FIRE EFFECT ON PLANT
• DISCUSSION AND QUALIFICATION OF FIRE EFFECT
• PLANT RESPONSE TO FIRE
• DISCUSSION AND QUALIFICATION OF PLANT RESPONSE
• FIRE MANAGEMENT CONSIDERATIONS

IMMEDIATE FIRE EFFECT ON PLANT:

Fire will partially or completely kill narrowleaf cottonwood depending upon severity. Mature narrowleaf cottonwood possesses thick-furrowed bark; however, the bark does not always provide adequate insulation, leaving trunks vulnerable to heat-induced xylem cavitation and scarring. Even low-severity fires may wound trees, resulting in either complete or partially killed crowns [32]. Due to limited root systems, narrowleaf cottonwood seedlings and saplings on well-drained alluvial bars are very susceptible to severe fires [41].

DISCUSSION AND QUALIFICATION OF FIRE EFFECT:

No entry

Narrowleaf cottonwood resprouts from roots,  healthy and fire damaged branches, and root crowns  [32]. Postfire sprouting generally occurs after light- to moderate-severity fire in pole sized and recently mature stands [41].

The ability to produce postfire sprouts is greatly affected by stand age and location of the water table. Sprouting potential decreases proportionally as mature trees age. High water tables aid in the sprouting ability and subsequent sprout survival [38]. See "Plant Response to Fire" in the "Fire Effects" section of the FEIS summary of black cottonwood for further information on sprouting response of narrowleaf and other cottonwoods.

Gom and Rood [32] observed copious sprouting 5 months after a severe April wildfire along the Oldman River near Lethbridge, Alberta. Newly emerged sprouts were observed by 2 postfire months. Buried root crowns of stems less than 3.9 inches (10 cm) diameter were found to produce new adventitious sprouts even when completely burned,  sometimes to several centimeters below the soil surface. Copious sprouting may occur from buried roots of live trunks with all severities of damage [32]. No evaluations of natural postfire establishment through seed are currently available. 

Due to decreased probability of postfire sprouting by older mature tress, prescribed fires in narrowleaf cottonwood stands are not recommended past pole and early maturation stages of development [38]. Livestock grazing should be excluded for at least five years after fire, with wildlife browsing monitored [40].

Related categories for SPECIES: Populus angustifolia | Narrowleaf Cottonwood