Preventing invasion following restoration
Fire can provide germination and establishment opportunities for native and invasive plant species. Many fire restoration projects fail due to subsequent invasion by exotic species. I am examining the effects of seed addition, high-intensity prescribed fire and competition reduction in native-dominated and invasive-dominated savannas. Seeds of 17 species were added to plots that were either burned, clipped, or unmanipulated and initially native-dominated or invasive-dominated.
We are finding that high-intensity (summer) fire is effective at reducing the invasive grass and promoting the establishment of native species. Invasive-dominated plots were more heavily burned and easily colonized post-fire than native-dominated plots. Early successional species were best able to establish post-fire. The native congener to the invader was successful at establishing in all treatments. However, restoration method seems to be more important than species choice in promoting native species establishment, survival, and resistance to future invasion. This suggests that restoration projects should include species with a variety of traits and attempt novel restoration techniques such as high-intensity prescribed fires.
This research was presented at the Ecological Society of America, here is the abstract.
We are finding that high-intensity (summer) fire is effective at reducing the invasive grass and promoting the establishment of native species. Invasive-dominated plots were more heavily burned and easily colonized post-fire than native-dominated plots. Early successional species were best able to establish post-fire. The native congener to the invader was successful at establishing in all treatments. However, restoration method seems to be more important than species choice in promoting native species establishment, survival, and resistance to future invasion. This suggests that restoration projects should include species with a variety of traits and attempt novel restoration techniques such as high-intensity prescribed fires.
This research was presented at the Ecological Society of America, here is the abstract.
Why are oaks not regenerating?
Central Texas woodlands were historically co-dominated by juniper and hardwoods, specifically Texas red oak. They are the habitat of the endangered golden-cheeked warbler. Hardwoods are currently not regenerating, juniper is regenerating. I am investigating the effects of low-intensity prescribed fire and deer herbivory in these woodlands. The management goal is to restore the process of oak regeneration so these woodlands will continue to support the endangered warbler.
I started this project in 2009 with the help of Balcones Canyonlands NWR. We have 4 years of data. Fire increased the number of oak and other hardwood sprouts per tree. Both fire and fencing were required for these sprouts to grow above the deer browseline. Fire also reduced the number of juniper saplings and increased the number of hardwood saplings.
This research was presented at the Ecological Society of America, here is the abstract.
I started this project in 2009 with the help of Balcones Canyonlands NWR. We have 4 years of data. Fire increased the number of oak and other hardwood sprouts per tree. Both fire and fencing were required for these sprouts to grow above the deer browseline. Fire also reduced the number of juniper saplings and increased the number of hardwood saplings.
This research was presented at the Ecological Society of America, here is the abstract.