FIRE EFFECTS
SPECIES: Elymus lanceolatus | Thickspike Wheatgrass 



IMMEDIATE FIRE EFFECT ON PLANT : 
Fires usually consume dry vegetation to ground level.  Burning
thickspike wheatgrass, with its coarse stems and lesser amounts of leafy
material, usually results in rapid combustion and little downward
transfer of heat to belowground plant parts [44].  The rhizomatous
growth form of this species minimizes the effect of fire on it.


DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
Burns conducted in the spring after new growth is initiated can severely
injure this species [44].


PLANT RESPONSE TO FIRE : 
Growth habit and season of burn are the principle variables regulating
the response of grasses to fire [38].  Rhizomatous species are
frequently favored by fire, as fire probably stimulates the initiation
of new shoots at primordial regions of the root system.  Thickspike
wheatgrass increases in abundance following fire [42].  Production on
burned plots remains above that on controls for about 30 years [21].
Postburn recovery time is rapid (2 to 5 years) in the sagebrush and
pinyon-juniper zones of the Intermountain region [44].  Thickspike
wheatgrass recovers more rapidly on ungrazed pastures than on grazed
experimental plots [10,26,33].


DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
On a sagebrush-grass range on the Upper Snake River Plains, Idaho,
thickspike increased markedly on burned areas by the end of the first
growing season after fall burns.  The degree of increase rose with the
intensity of the burn.  This relative increase continued so that by the
end of the third year, production doubled or tripled that on the
unburned range.  Thickspike usually recovers fully within 3 years of a
fire.  After 15 years relative production declined, but thickspike
wheatgrass still produced significantly more on the burned range than on
the unburned one [8].

On a western wheatgrass and thickspike wheatgrass range in southeastern
Alberta, 1 year after an August wildfire, production of the two grasses
was reduced 19 percent [43].

An effect of fire is to increase water stress on plants on burned sites.
An accidental fire in Saskatchewan burned a strip of thickspike
wheatgrass-junegrass prairie several hundred feet wide.  Sampling was
done along burned and unburned sides of the fire line.  Plant and soil
water stress increased near the end of the May-August period following
the fire on both burned and unburned sites.  As the growing season
progressed, the potentials in thickspike wheatgrass became lower on
burned plots.  Observed reductions in productivity were probably the
result of increased plant water stress [45].  In an experiment using
thickspike wheatgrass leaves, water potential and osmotic potential were
lower in plants from burned areas [43].


FIRE MANAGEMENT CONSIDERATIONS : 
NO-ENTRY

Related categories for Species: Elymus lanceolatus | Thickspike Wheatgrass