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In 1997, the LTER (Milchunas and others) and the USFS initiated a
fire study with the dual objectives of assessing the use of fire as management practice to
increase nesting habitat for mountain plovers, and examining the effects of fire on plant
community structure and productivity. Fire is an integral component of many productive
grassland ecosystems such as the tallgrass prairie of the North American Great Plains. A
large number of comprehensive studies on fire effects have been conducted in these
systems. Because of the low fuel loads, pre-settlement fires probably affected less
extensive areas in systems such as the shortgrass steppe. However, small lightning fires
may have been frequent in shortgrass steppe, and fire impacts in this system are poorly
understood.
The vegetation component of the fire study is assessing 1) aboveground net primary
productions, 2) plant nitrogen concentration and yield, 3) canopy cover, 4) cactus
mortality, and 50 shrub condition. Preliminary data indicate no significant effect of fire
on ANPP or on aboveground plant-tissue N-concentrations. The first year’s fire was,
however, followed by a year of well-above-average precipitation. Although not yet
statistically analyzed, some cactus cladode injury was observed, and resprouting from
injured plants was greater than new cladode formation on control area. Measurements will
continue through after each burn to assess further impacts.
03/21/02
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