Pine foliage samples of 1.00, 0.50, and 0.25 g were ground in either a Wiley mill or a shatterbox, ashed, subjected to either HF or HNO3 digestions, and analyzed for element concentrations. Grinding methods had little effect on estimated mean element concentrations. The 1.00 g sample size was preferable, but few differences were observed with the 0.50 g sample. However, the 0.50 g weight is probably approaching the minimum for conventional grinding and analytical methods. Both acid digestions were equally effective in dissolving major elemental constituents, but the HF method was superior for the micronutrients, especially Mn. Variability associated with the major elements was similar for all combinations of grinding, acids, and the two larger sample weights. For analysis of the minor elements, the best combination was the 1.00 g sample, shatterbox grinding, and HF digestion. Analysis of 1.00 g samples of National Institute of Standards and Technology pine needles, Standard Reference Material No. 1575, digested in HF acid compared very well with the NIST certified values.
