FIRE AND NITROGEN EFFECTS ON RED THREE-AWN COMMUNITIES IN THE NORTHERN PLAINS
Livestock and Range Research Laboratory (LARRL)
2012 Annual Report
1a.Objectives (from AD-416):
Determine effects of summer and fall fire and nitrogen addition on red three-awn communities.
1b.Approach (from AD-416):
A 3x3 factorial arrangement of fire and fertilizer treatments will be applied on 2 sites over 2 years and monitored 2years following treatment to examine effects of no fire, summer or fall fire and no nitrogen addition or addition of 40 or 80 kg/ha on red three-awn communities. Increased nitrogen availability will likely improve the ability of other species to establish and compete with red three-awn. Summer fire should be detrimental to red three-awn because of the plant's growth pattern and bunchgrass habit. Treatment effects will be evaluated by measuring standing crop, plant species composition and plant diversity before treatment and 2 years post-treatment.
Second-year post-treatment data have been collected and first-year data have been collected for the repeated experiment to assess fire and nitrogen effects. Response data have been collected for simulated grazing treatments to determine utilization effects on three-awn and coexisting species. Laboratory analyses of fire and fertilizer effects on three-awn diet quality have been conducted for the repeated experiment. A manuscript is in preparation from greenhouse data on fire, clipping, and competition effects.