Assessment of bias in carbon isotope composition of organic leaf matter due to pre‐analysis milling methods

Rationale Stable isotope analysis of leaf material has many applications including assessment plant water-use efficiency and palaeoclimatology. To facilitate interpretations small shifts in the carbon composition (δ13C) leaves, accurate repeatable results are required. Pre-sample homogenisation is essential to ensure a representative sample analysed, but can also introduce error. Methods We investigate how different grinding methods (freezer-milling ball-milling) affect content δ13C tree leaves from wetland Queensland, Australia, commenting on increased temperature, contamination, loss or poor may impact results. Results No alteration observed due milling methods, although there be significant increase %C samples processed using ball-milling. Conclusions suggest variability possibly contamination abraded plastic vials insufficient during ball-milling, with no δ13C. Overall, we that intermittent ball-milling best solution reduce costs, preparation time use liquid nitrogen, aiming achieve complete shortest possible duration milling.