TEF plot

The study site was the Tomakomai Experimental Forest (TEF; 42°40′ N, 141°36′ E) permanent plot located in central Hokkaido. The TEF plot was located on a flat plateau with inclines of <5° and elevations ranging from 20 to 90 m. The mean annual temperature and precipitation were 7.0°C and 1200 mm, respectively. The soil in the TEF is typically of volcanic origin. No. 15 typhoon removed 49% of standing trees (diameter at breast height [DBH] ≥ 5 cm) and 81% of basal area in September 1954. The TEF plot was established in 1958 and the pre-disturbance condition was reconstructed based on the first measurements made after the windthrow. The pre-disturbance forest type was hardwood dominated by Quercus spp., Acer spp., Ostrya japonica, and Tilia spp. All trees with a DBH (1.3 m above the ground) ≥ 5 cm were identified and measured during every survey. Tree measurement was taken 10 times 65 years after the windthrow. Salvage logging was not conducted; no trees were harvested after the windthrow. A permanent plot measuring 50 × 50 m (0.25 ha) was set up in 1958. The taxonomic nomenclature used here follows Yonekura and Kajita (2003–).