{"id":"chojnacky-2014-woodland-fagaceae","source":{"id":"chojnacky-2014","citation":"Chojnacky, D.C., Heath, L.S., Jenkins, J.C. (2014). Updated generalized biomass equations for North American tree species. Forestry, 87(1), 129–151.","title":"Updated generalized biomass equations for North American tree species","authors":["Chojnacky, D.C.","Heath, L.S.","Jenkins, J.C."],"year":2014,"venue":"Forestry: An International Journal of Forest Research","doi":"10.1093/forestry/cpt053","url":"https://doi.org/10.1093/forestry/cpt053","read_url":"https://research.fs.usda.gov/download/treesearch/45402.pdf","access":"open","checked_at":"2026-11-01","status":"current"},"name":"North American taxa group: woodland Fagaceae (Table 5)","output":{"quantity":"agb"},"expression":"exp(-3.0304 + 2.4982 * ln(DRC))","published":{"expression":"exp(-3.0304 + 2.4982 * ln(drc))","units":{"drc":"cm"},"variables":{"drc":"DRC"},"output_unit":"kg"},"taxon":{"level":"mixed","name":"Woodland Fagaceae (Quercus douglasii, Q. gambelii, Q. hypoleucoides, Quercus (live) spp.)","family":"Fagaceae","group":"broadleaf","members":["Quercus douglasii","Quercus gambelii","Quercus hypoleucoides"],"members_complete":false},"region":{"scope":"national","countries":["US"],"place":"United States (equations compiled from US and Canadian studies)","biomes":["temperate","dryland"]},"stand":"mixed","fit":{"r2":0.84,"method":"Weighted regression of ln(biomass) on ln(drc) fitted to 36 pseudodata points generated from 5 published equations; no back-transform correction"},"evidence":[{"field":"expression","quote":"ln(biomass) = β0 + β1 ln(diameter)","locator":"Table 5 caption, p. 140"},{"field":"expression","quote":"Fagaceae 0.59 −3.0304 2.4982 36 5 drc 3–74 0.84","locator":"Table 5 row, p. 140"},{"field":"taxon","quote":"Fagaceae Q. gambelii Oak, Gambel 814 0.61 2","locator":"Table 4, p. 138"},{"field":"fit.cf","quote":"we did not include a correction (Baskerville, 1972) for underestimation","locator":"Methods, p. 139"}],"check":[{"inputs":{"DRC":30},"expected":236.6237,"origin":"computed","note":"computed from the published form at drc = 30 cm"}],"verification":"original_read","checked_at":"2026-11-03","notes":"Woodland oaks (blue, Gambel, silverleaf and evergreen live oaks), by root-collar diameter. Root-collar diameter range of the pseudodata: 3–74 cm. Median specific gravity of the group: 0.59. R² is the published 'R²-statistic'."}