Fig. 3. Comparison of actual DPAC (a, c, and e) pH and (b, d, and f) lime requirement (LR) values with values estimated by cross validation of block kriging based on either the most dense point sampling strategy (•, 10 [CP_0.1ha] or 5 [P_0.2ha] points ha^–1) or a sparser strategy of 2.5 points ha^–1 (P_{0.4 ha}). Estimated CP_0.1ha/P_0.2ha values are from cross validation while estimated P_{0.4 ha} values represent the combination of results from cross and jackknife validation.