Whistler Biosolids Forest Fertilization Program (EP1177)
It was anticipated that forest biosolids fertilization could achieve the dual benefits of improved soil fertility and tree growth in nitrogen-deficient Douglas-fir plantations of the Whistler Interpretive Forest, while providing an economic and environmentally safe disposal for Whistler’s municipal sewage biosolids. This experiment was established as a co-operative study between the BC Ministry of Forests, the University of British Columbia and the Resort Municipality of Whistler, to determine if these results were achievable was established
- To compare fertilization of Douglas-fir with biosolids at 750, 1000, and 1500 kg-Nitrogen/hectare (N/ha) and conventional fertilizer at 225 kg-N/ha, and
- To compare the growth response with season of fertilizer application (spring, summer and fall).
The experiment was established in 1993 near Whistler, B.C. in a 15-year-old, nutrient deficient Douglas-fir plantation that had been thinned to 600 stems/ha and pruned to 3 m height the year before. Season of application was tested by applying the fertilizers in 3 areas (blocks) with each block fertilized in a different season: summer (August 1993), fall (September, 1993) and spring (June, 1994). The five fertilizer treatments (750, 1000, and 1500 kg/N/ha applied as biosolids, a conventional fertilizer at 225 kg-N/ha, and an unfertilized control) were tested in 0.09-ha plots with 2 plots per block receiving the same treatments (10 plots per block or 30 plots in total).
- Girard, A. 2014. A five-year comparison, between fertilizer and biosolids, of yield in a coastal Douglas-fir plantation: an eighteen year post fertilization growth response assessment. BScF thesis. Univ. British Columbia, Vancouver, B.C.
- de Montigny, L. and S. Stearns-Smith. 2001. Douglas-fir fertilization with biosolids: five-year results at Whistler, B.C. B.C. Min. For., Victoria, B.C. Exten. Note 50.
- Zhong, A. 1998. Efficacy of secondary biosolids fertilization in a managed Douglas-fir forest in the Coastal Western Hemlock zone of British Columbia. PhD thesis. Univ. British Columbia, Vancouver, B.C.