Details

Autor(en) / Beteiligte

• Lodge, Alexandra G.
• Whitfeld, Timothy J. S.
• Roth, Alexander M.
• Reich, Peter B.
• Price, Jodi

Titel

Invasive plants in Minnesota are "joining the locals": A trait-based analysis

Ist Teil von

• Journal of vegetation science, 2018-07, Vol.29 (4), p.746-755

Ort / Verlag

Hoboken: John Wiley & Sons Ltd

Erscheinungsjahr

2018

Quelle

Wiley Online Library

Beschreibungen/Notizen

• Questions: Predicting which newly arrived species will establish and become invasive is a problem that has long vexed researchers. In a study of cold temperate oak forest stands, we examined two contrasting hypotheses regarding plant functional traits to explain the success of certain non-native species. Under the "join the locals" hypothesis, successful invaders are expected to share traits with resident species because they employ successful growth strategies under light-limited understorey conditions. Instead, under the "try harder" hypothesis, successful invaders are expected to have traits different from native species in order to take advantage of unused niche space. Location: Minnesota, USA. Methods: We examined these two theories using 109 native and 11 non-native plants in 68 oak forest stands. We focused on traits related to plant establishment and growth, including specific leaf area (SLA), leaf carbon-to-nitrogen ratio (C:N), wood density, plant maximum height, mycorrhizal type, seed mass and growth form. We compared traits of native and non-native species using ordinations in multidimensional trait space and compared community-weighted mean (CWM) trait values across sites. Results: We found few differences between trait spaces occupied by native and non-native species. Non-native species occupied smaller areas of trait space than natives, yet were within that of the native species, indicating similar growth strategies. We observed a higher proportion of non-native species in sites with higher native woody species CWM SLA and lower CWM C:N. Higher woody CWM SLA was observed in sites with higher soil pH, while lower CWM C:N was found in sites with higher light levels. Conclusions: Non-native plants in this system have functional traits similar to natives and are therefore "joining the locals." However, non-native plants may possess traits toward the acquisitive end of the native plant trait range, as evidenced by higher non-native plant abundance in high-resource environments.