Litter Production in Western Washington Douglas-Fir Stands

Litter production by Douglas-fir stands ranging in age from22 years old to 160 years old, is discussed. Typical leaf litterproduction was 2100 kg ha^–1 yr^–1 while total litterwas 2500 kg ha^–1 yr^–1. Annual fall of leaf litterincreases up to about 40 years of age and then becomes fairlyconstant while total litter continues to increase because ofwood production, although this increase may be quite irregular.Average nutrient returns to the forest floor are 21, 3, 7, 32,4, and 7 kg ha^–1 yr^–1 for N, P, K, Ca, Mg, and Mnrespectively.