Tomakomai plot

The study site was the Tomakomai (42°43′ N, 141°27′ E) permanent plot in the Japanese National Forest, located in central Hokkaido. 

 The Tomakomai plot was on a flat slope at an elevation of approximately 300 m. The soil was volcanic origin. The mean annual temperature was 6.9°C and precipitation was 1,711 mm. No. 15 typhoon removed 85% of standing trees (diameter at breast height [DBH] ≥ 5 cm) and 93% of basal area in September 1954. The Tomakomai plot was established in 1956 and the pre-disturbance condition was reconstructed based on the first measurements made after the windthrow. All trees with a DBH (1.3 m above the ground) ≥ 5 cm were identified and measured during every survey. Tree measurement was taken 14 times 65 years after the windthrow. Salvage logging was not conducted; no trees were harvested after the windthrow. The plot area was 0.50 ha (50 × 100 m); a surrounding buffer zone of 1.17 ha was established. Wind disturbance occurred again in 2004, when 6% of trees and 7% of the basal area were damaged.

 The pre-disturbance forest comprised a natural coniferous stand in which conifers, such as Picea jezoensis and Abies sachalinensis, accounted for 93% of basal area. The conifers were mixed with 13 hardwood species, such as Magnolia obovata, Quercus crispula, Acer pictum (including A. pictum ssp. mono and A. pictum ssp. mayrii), and Phellodendron amurense.

 The taxonomic nomenclature used here follows Yonekura and Kajita (2003–).