SUMMARY
Soils in wild lowbush blueberry production are prone to wind erosion and have very low nutrient and water storage capacities. An experiment was initiated to assess paper mill biosolids (PB) mixed with wood ash and ground bark as a soil amendment/fertilizer for wild lowbush blueberry (Vaccium angustifolium Ait.) in the Lac St-Jean area, Quebec, Canada. A mixture of PB was applied during spring (mid-May) of the sprout year (1998) on 120 m2 plots at a rate of 15t ha−1 (wet basis) with wood ash (1 and 2t ha−1) and ground bark (0, 3, 6,9 and 15t ha−1, wet basis). Blueberry leaves were sampled in the first year and wet digestion and dry ashing were performed to determine foliar nutrient concentration. In 1999 and 2000, fruit yields tended to increase with PB with wood ash and ground bark application (31% in 1999 and 29% in 2000). Foliar N, P and K concentrations were increased whereas Ca and Mg were unaffected compared to control. Other nutrients were also determined and only Fe tended to increase with PB application whereas Ni tended to decrease. This study indicated that PB mixed with wood ash and ground bark is a potential nutrient source for blueberry on these poor sandy soils without short-term loss in crop yield.