Post‐fire regeneration inMediterranean reforested sites as affected by mechanical site preparation: lessons for restoration

AbstractQuestionThe importance of silvicultural site preparation techniques in determining vegetation succession is increasingly recognized. We studied the effects of mechanical site preparation (MSP) on post‐fire vegetation regeneration within reforested sites inMediterraneanIsrael.LocationUpperGalilee region,Israel.MethodsVegetation cover and composition, ruderal species colonization and pine regeneration were monitored in four reforested sites for 3 yr following wildland fires that burned maturePinus brutiaandP. halepensisplantations. In each reforested site, a 50 m × 50 m monitoring area was assigned and measurements were conducted within five subplots (2 m × 50 m) encompassing threeMSPpatch types: ploughed patches (P), unploughed patches (UP) and planting mounds (M) that combined ploughing, pit digging and wood‐chip mulching.ResultsRecovery of vegetation cover (excluding pines) was rapid. TheMSPpatch type significantly affected vegetation cover in the first spring following the fire: cover was lowest onM, intermediate onPand highest onUP. However, these differences became minor by the third spring following the fire. Total woody species richness was not affected byMSPpatch type, although there were minor effects on relative abundance of woody species. Two ruderal species were found, but their abundance became untraceable by the third year. Patterns ofMSPeffects on pine regeneration were similar forP. halepensisandP. brutia. Density of emerging seedlings of both pine species during the first year following the fire was significantly affected by MSP patch type: lower inPandMthan inUPby more than 50% and 90%, respectively. However, emergence and/or survival during the following 2 yr was higher inPandMthan inUP, with overall outcome of pine regeneration still about 50% lower inPandMthan inUP.ConclusionsTheMSPtreatments had only a minor, short‐term effect on post‐fire regeneration and colonization of vegetation, except for pine recruitment, which was more severely affected.