trations ranging from tens of ng per g of dry wood for trace metals to hundreds of mg g -1 for the alkaline earths (Olsson et al., 1999), a multi-element technique is required that combines excellent detection limits with a large dynamic range.Modern approaches to trace metal analysis of tree cores fall in two categories. One is the use of non-destructive surface spectroscopic techniques such as secondary ion mass spectrometry (SIMS) (Martin et al., 1997), micro-synchrotron X-ray fluorescence (mSXRF) (Martin et al., 2006), or laser ablation ICP-MS (Hoffmann et al., 1994). Their main advantage is outstanding spatial resolution due to a typical beam size of ~100 mm, yet this can actually be perceived as a disadvantage, since heterogeneity on length scales much smaller than the width of a ring tends to obfuscate annual cycles (Brabander et al., 1999), a problem that also plagues other temporal geochemical records, like corals (Sinclair et al., 1998;Giry et al., 2010). More pertinent disadvantages are long analysis times, often inadequate detection limits, and a lack of suitable standards that may give rise to merely semi-quantitative results. Nonetheless, laser ablation ICP-MS analysis has been used to convincingly link metal abundances or distributions in xylem and bark with known areal pollution histories (