Earthworms, stand age, and species composition interact to influence particulate organic matter chemistry during forest succession Susan E. Crow Timothy R. Filley Melissa McCormick Katalin Szla ´vecz Diane E. Stott David Gamblin Grace Conyers Received: 15 April 2008 / Accepted: 1 November 2008 / Published online: 21 November 2008 Ó Springer Science+Business Media B.V. 2008 Abstract The landscapes colonized by invasive earthworms in the eastern U.S. are often patchworks of forest stands in various stages of successional development. We established six field sites in tulip poplar dominated forests in the Smithsonian Envi- ronmental Research Center in Edgewater, MD, that span mid (50–70 years-three plots) and late (120– 150 years-three plots) successional stages where younger sites had greater earthworm density and biomass than older sites and were dominated by non- native lumbricid species. In particular Lumbricus rubellus, a litter-feeding species, was abundant in mid successional forests. Here, we separated particulate organic matter (POM) from the bulk soil by a combination of size and density fractionation and found that patterns in soil POM chemistry were similar to those found previously during litter decay: in younger forests with high abundance of earth- worms, organic carbon normalized cutin- and suberin- derived substituted fatty acid (SFA) concentration was lower and lignin-derived phenols greater than in older forests where earthworms were less abundant. The chemistry of the dominant litter from mid versus late successional tree species did not fully explain the differences in POM chemistry between age classes. Instead, the differences in leaf body versus petiole and leaf versus root chemistry were the dominant drivers of POM chemistry in mid versus late successional stands, although aspects of stand age and tree species also impacted POM chemistry. Our results indicate that preferential ingestion of leaf body tissue by earthworms and the subsequent shifts in sources of plant biopolymers in soil influenced POM chemistry in mid successional forests. These results indicate that invasive earthworm activity in North American for- ests contributes to a shift in the aromatic and aliphatic composition of POM and thus potentially influences carbon stabilization in soil. Keywords Cutin  Invasive earthworms  Lignin  Litter quality  Forest succession  Particulate organic matter  Suberin  Soil organic matter S. E. Crow  T. R. Filley  D. Gamblin  G. Conyers Department of Earth and Atmospheric Sciences, Purdue University, West Lafayette, IN, USA S. E. Crow (&) 14 CHRONO Centre for Climate, the Environment, and Chronology, Queen’s University Belfast, 42 Fitzwilliam St., Belfast BT9 6AX, UK e-mail: s.crow@qub.ac.uk M. McCormick Smithsonian Environmental Research Center, Edgewater, MD, USA K. Szla ´vecz Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, MD, USA D. E. Stott USDA-ARS National Soil Erosion Research Laboratory, West Lafayette, IN 47907-2077, USA 123 Biogeochemistry (2009) 92:61–82 DOI 10.1007/s10533-008-9260-1