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Abstract Changes in climate and land management over the last half‐century have favoured woody plants native to grasslands and led to the rapid expansion of woody species. Despite this being a global phenomenon, it is unclear why some woody species have rapidly expanded while others have not. We assessed whether the most abundant woody encroaching species in tallgrass prairie have common growth forms and physiology or unique traits that differentiate their resource‐use strategies.We characterized the abundance, above‐ground carbon allocation, and leaf‐level physiological and structural traits of seven woody encroaching species in tallgrass prairie that span an order of magnitude in abundance. To identify species‐specific increases in abundance, we used a 34‐year species composition dataset at Konza Prairie Biological Station (Central Great Plains, USA). We then compared biomass allocation and leaf‐level traits to determine differences in carbon and water use strategies among species.While all focal species increased in abundance over time, encroachment in this system is primarily driven by three species:Cornus drummondii,Prunus americanaandRhus glabra. The most dominant species,Cornus drummondii, had the most extreme values for several traits, including the lowest leaf:stem mass ratios, lowest photosynthetic capacity and highest turgor loss point.Two of the most abundant species,Cornus drummondiiandRhus glabra, had opposing growth forms and resource‐use strategies. These species had significantly different above‐ground carbon allocation, leaf‐level drought tolerance and photosynthetic capacity. There were surprisingly few interspecific differences in specific leaf area and leaf dry matter content, suggesting these traits were poor predictors of species‐level encroachment.Synthesis. Woody encroaching species in tallgrass prairie encompass a spectrum of growth forms and leaf physiology. Two of the most abundant woody species fell at opposite ends of this spectrum. Our results suggest niche differences among a community of woody species facilitate the rapid encroachment by a few species. This study shows that woody encroaching species do not conform to a ‘one‐size‐fits‐all’ strategy, and a diversity of growth forms and physiological strategies may make it more challenging to reach management goals that aim to conserve or restore grassland communities.
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This content will become publicly available on June 24, 2026
Why are non‐native plants successful? Consistently fast economic traits and novel origin jointly explain abundance across US ecoregions
Summary Are non‐native plants abundant because they are non‐native, and have advantages over native plants, or because they possess ‘fast’ resource strategies, and have advantages in disturbed environments? This question is central to invasion biology but remains unanswered.We quantified the relative importance of resource strategy and biogeographic origin in 69 441 plots across the conterminous United States containing 11 280 plant species.Non‐native species had faster economic traits than native species in most plant communities (77%, 86% and 82% of plots for leaf nitrogen concentration, specific leaf area, and leaf dry matter content). Non‐native species also had distinct patterns of abundance, but these were not explained by their fast traits. Compared with functionally similar native species, non‐native species were (1) more abundant in plains and deserts, indicating the importance of biogeographic origin, and less abundant in forested ecoregions, (2) were more abundant where co‐occurring species had fast traits, for example due to disturbance, and (3) showed weaker signals of local environmental filtering.These results clarify the nature of plant invasion: Although non‐native plants have consistently fast economic traits, other novel characteristics and processes likely explain their abundance and, therefore, impacts.
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- Award ID(s):
- 2217817
- PAR ID:
- 10620612
- Publisher / Repository:
- New Phytologist
- Date Published:
- Journal Name:
- New Phytologist
- ISSN:
- 0028-646X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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