White-tailed deer (Odocoileus virginianus) hunting is an important economic activity associated with the management of forests and rangelands in the USA, with over $12.9 billion dollars of related annual expenditures.
Reducing tree cover through thinning and prescribed fire both have the potential to increase the quantity and
quality of deer forage. We evaluated the long-term impacts of eight different combinations of fire return intervals
and tree harvest on forage productivity and protein content of the forage. Based on management regime, study
units ranged from savanna to closed-canopy forest. Aboveground net primary production (ANPP) of six functional groups (grass, panicum, forb, legume, woody, sedge) of understory vegetation was measured in October
2019 and 2020 using destructive sampling. Samples for foliar crude protein (CP) concentration were collected in
spring, summer, and fall of 2020. Total understory ANPP ranged from 2.9 to 466.3 g m− 2 and was up to 566%
greater in savanna systems maintained by frequent fire (return interval of three years or less) than in non-burned
forest treatments. Annual burning resulted in ANPP dominated by herbaceous plants composed mostly of firetolerant grasses (e.g., Andropogon gerardii, Schizachyrium scoparium). Longer fire return intervals or no fire
resulted in roughly equal ANPP from understory woody and herbaceous species. Crude protein concentrations
were up to 45.7% greater in the woodland and forest units than in the savanna units for seven of the eleven
species sampled. The greater CP in the forests was most noticeable in the summer when deer needs for quality
forage are substantial. Increased protein concentrations of understory species in the forests, but greater ANPP in
the savannas indicate that managing for a mix of savanna and woodland could be ideal for balancing forage
quantity with increased forage protein.
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This content will become publicly available on July 1, 2024
Herbaceous vegetation responses to experimental fire in savannas and forests depend on biome and climate
Fire–vegetation feedbacks potentially maintain global savanna and forest distributions. Accordingly, vegetation in savanna and forest ecosystems should have differential responses to fire, but fire response data for herbaceous vegetation have yet to be synthesized across biomes. Here, we examined herbaceous vegetation responses to experimental fire at 30 sites spanning four continents. Across a variety of metrics, herbaceous vegetation increased in abundance where fire was applied, with larger responses to fire in wetter and in cooler and/or less seasonal systems. Compared to forests, savannas were associated with a 4.8 (±0.4) times larger difference in herbaceous vegetation abundance for burned versus unburned plots. In particular, grass cover decreased with fire exclusion in savannas, largely via decreases in C4grass cover, whereas changes in fire frequency had a relatively weak effect on grass cover in forests. These differential responses underscore the importance of fire for maintaining the vegetation structure of savannas and forests.
more » « less- NSF-PAR ID:
- 10478449
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- John Wiley & Sons Ltd
- Date Published:
- Journal Name:
- Ecology Letters
- Volume:
- 26
- Issue:
- 7
- ISSN:
- 1461-023X
- Page Range / eLocation ID:
- 1237 to 1246
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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