Growth traits and potential invasiveness of Acer species
Invasive tree species can have significant detrimental impacts on the habitats they invade including outcompeting native biodiversity and altering the structure and composition of habitats. Acer species have been widely introduced throughout the world due to their ornamental or wood production properties. Identifying potentially invasive Acer species before they become problematic can prevent expensive management costs and reduce effects on ecosystem services. Eight Acer species were studied (Table 1), and performance traits were compared with their invasiveness (expressed as the number of regions and countries invaded). Seeds of eight species were collected from arboreta and parks in Belgium, and from suppliers from the United Kingdom and France. Seeds (between 24 and 42 per species) were planted and grown under controlled conditions. Measured traits were relative growth rate (RGR), specific leaf area (SLA), height, number of leaves of seedlings and shoot-root ratio. Seedlings were harvested and measured after 2, 4 and 8 weeks. Overall, RGR, SLA, height and number of leaves after 8 weeks were positively correlated with the invasiveness of the species. Interestingly, A. rufinerve (EPPO List of Invasive Alien Plants) was highlighted in the study as a species with low invasiveness due to the low number of countries it has currently invaded, but it has a high RGR and SLA. This may indicate that A. rufinerve has not completed its invasion process yet and the species should be closely monitored in temperate countries to avoid invasions into natural habitats.
Table 1. Eight species of Acer included in the study.
Species | Native range | Regions invaded |
Acer negundo | North America | Africa, Asia, Europe, Oceania, South America |
Acer pseudoplatanus | Europe | Africa, Asia, Europe, Oceania, South America |
Acer platanoides | Europe | Europe, North America, Oceania |
Acer campestre | Europe | Europe, North America |
Acer palmatum | East Africa | Asia, Europe, North America |
Acer saccharum | North America | Asia, Europe |
Acer rufinerve | North America | Europe |
Acer lobelii | Europe | Europe |
Sources
Aurore F, Grégory M, Arnaud M (2022) Can we foresee future maple invasions? A comparative study of performance-related traits and invasiveness of eight Acer species. Plant Ecology 223, 1181–1192. https://doi.org/10.1007/s11258-022-01266-1