Robinia pseudoacacia invasion in Castanea sativa forests
Robinia pseudoacacia (Fabaceae) is native to North America and is found in the EPPO region where it has been planted for afforestation, wood provisioning and erosion control along mountain slopes. In the Mediterranean region, R. pseudoacacia can invade Castanea sativa (Fagaceae) forests which are common man-made forests covering approximately two million hectares in Italy. In Southern Switzerland and Northern Italy, R. pseudoacacia has replaced entire valleys of C. sativa coppice forests. In the Vesuvius National Park (Italy), R. pseudoacacia has colonised unmanaged C. sativa coppice forests following disturbance in 2017 by forest fires. In 5 plots (300 x 600 m), the competitive functional traits (including regeneration strategies) of each species were assessed. The production of basal sprouts and root-suckers in R. pseudoacacia was stimulated by fire disturbance. This double vegetative regeneration strategy gives R. pseudoacacia a competitive advantage over C. sativa. The abundance of root suckers and their regeneration and spread, up to 10 m from the parent plant, acts to colonise areas of C. sativa stands. When considering management measures, control options for R. pseudoacacia tree sprouting are required to maintain a continuous canopy cover of C. sativa.
Sources
Saulino L, Rita A, Stinca A, Liuzzi G, Silvestro R, Rossi S and Saracino A (2023) Wildfire promotes the invasion of Robinia pseudoacacia in the unmanaged Mediterranean Castanea sativa coppice forests. Frontiers in Forest and Global Change 6, 1177551. https://doi.org/10.3389/ffgc.2023.1177551