Insect damage to cones and other mortality factors limiting natural regeneration potential of Swiss stone pine (Pinus cembra L) in the northern French Alps

A seed cone population of Swiss stone pine was surveyed from flower bud burst to cone maturation during 1992-1993. The potential seed crop was estimated to decrease by 84% of the initial value. Mortality was mainly caused by abiotic factors during the first year of cone development while cone insects caused most damage to second-year cones. The cone entomofauna only included three phytophagous species, and largely differed from the fauna observed in cones of other Alpine conifers.