Burning and grazing cool-season grasslands to promote native grass recruitment for agronomic, ecological, and social benefits

Burning and grazing cool-season grasslands to promote native grass recruitment for agronomic, ecological, and social benefits

Summary

We combined burning and rotational grazing to blend restoration and livestock production by promoting and maintaining native and non-native grass coexistence. Native grass tiller density increased under the burn and graze treatments, but not the burn-graze treatment. However, native grass tillers in 2007 were higher in the burn only than the graze only treatment. We found no loss to native grass tiller density when rotational grazing was applied after 2 years of grazing exclusion with burning. Our results suggest that the use of burning and grazing as a management tool for native grass persistence may be possible with deferred grazing during establishment phase.

Objectives/Performance Targets

Results from this experiment will help determine whether burning and grazing can be combined for improved forage and root production (agronomic and ecological benefits). In addition, these practices will highlight farmers as land stewards, which promotes rural prosperity (social benefit).

The expected short-term outcomes of this project are:
1. Management techniques to promote the re-introduction and recruitment of warm season, native grasses into cool season, non-native grass pastures under grazing and burning practices.

2. Quantification of root production and forage production under grazing, burning, and a combination of grazing and burning.

The intermediate-term outcomes are:
1. Increase farm participation in the conservation effort by promoting the re-establishment of native plant species.

2. Burning for agricultural benefit should promote sustainable farming.

The long-term outcomes of this project will help many stakeholders (researchers, farmers, policy makers, general public, conservationists) envision the integration of conservation efforts with farm management. This model should encourage adoption of new techniques and practices that improve production while enhancing the environment. These outcomes strongly fit the mission of NCR-SARE, which strengthens farmer profitability while improving the environment by supporting sustainable research.

Accomplishments/Milestones

Results:
Native grass tiller density increased from 2006 to 2007 under the burn only (P = 0.006) and graze only (P = 0.005) treatments, but not the burn-graze treatment (P = 0.18). While 2 of 3 results were statistically significant, it is important to note the disparity in absolute native grass tiller density. Native grasses in burn plots increased from 19.8 ± 6.5 to 59.6 ± 7.3 while graze was only 1.0 ± 0.24 to 2.8 ± 0.11.

When comparing differences in native grass tiller density between 2006 and 2007, we found that the burn only treatment was significantly greater than the burn-graze and graze only treatments, while there was no significant difference between burn-graze and graze treatments.

Native grass cover in the burn treatment was significantly higher than in the burn-graze and graze treatments. There was no significant difference in native grass cover between burn-graze and graze treatments.

Visual assessment of ancillary data indicated little variability among treatments in soil temperature or gravimetric water content for 2007. However, net nitrogen mineralization appeared to be lower in the burn only plots than the graze only plots for June and October of 2007.

These results complete this research project.

Impacts and Contributions/Outcomes

Project outcomes:
1. Burning and rotational grazing can be successfully combined during the first year after 2 years of grazing exclusion with burning.
2. Coexistence between warm-season and cool-season grasses was obtained using burning and grazing management.
3. Root production increased under burning and forage production increased under grazing.
4. Contributed to on-going and future research in agroecosystems, especially in the use of native, warm-season grasses in livestock production.
5. Provides a sense of farmer pride and community awareness through the restoration of native flora while maintaining a working landscape.

This project worked closely with one farmer. Rotational grazing was already an established practice by the farmer. However, the farmer did adopt the use of prescribed burns to help promote the establishment of native grasses to their grassland pastures. Although the use of fire is well known east of the Mississippi River, it is a management tool that is seldom used in Wisconsin. The use of fire will continue on this particular farm in order to promote continued establishment throughout the landscape. Ongoing efforts consist of increasing farmer awareness on the benefits of using native, warm-season grasses, and the use of fire management.

Collaborators: