Eastern Redcedar is the most rapidly expanding woody plant species in the Great Plains and is now recognized as the number one threat to Nebraska’s rangelands by the Nebraska Conservation Roundtable. The impacts of redcedar invasion in grasslands are wide-ranging, including reducing grassland bird diversity and abundance, decreasing livestock production by 75%, reducing small mammal and insect diversity, and costing Nebraska Public Schools over $2,440,000 from 2006-2016.
GoalsThe objective of this grant is to assess the vulnerability of Nebraska’s grasslands to redcedar invasion, and develop predictive tools that enhance the potential to implement landscape interventions that (1) prevent the spread of redcedar trees or (2) restore degraded wildlife habitat following transformation to a redcedar-dominated state.
Two field experiments have been conducted since January 2018 with preliminary fire models conducted in BehavePlus, (Windows based fire management application to calculate fire behavior), and one manuscript is in its final stages before submission to a scientific journal. The first field experiment involved collecting thermal imaging data on extreme prescribed fires conducted in the Loess Canyons Biologically Unique Landscape (BUL). Information from these prescribed fires expanded on similar data collected in 2017 and will be used to validate future experimental investigations on extreme fire effects in grasslands as well as provide evidence for increased wildfire risk in juniper-invaded grasslands. The second field experiment was also conducted in the Loess Canyons BUL with the objective of quantifying rates of juniper recovery following extreme fire. This project was led by an undergrad student I advised that was enrolled in the USDA REU (research experience for undergrads) program. Data from the second field experiment show that Eastern Redcedar re-invades woodlands previously collapsed by extreme fire at surprisingly fast rates. Multiple mathematical fire models have been conducted in BehavePlus to quantify ember transport distances to better inform prescribed fire designs. Model outputs from these simulations will be used to quantify the maximum ember transport distance and likelihood of spotfire occurrence in large-scale prescribed fires.
Principal Investigator(s)-Dirac Twidwell, University of Nebraska-Lincoln
-Craig R. Allen, NE CFWRU