This archive contains datasets from a group of studies testing the hypotheses that leaf litter curling is influenced by plant species, hybridization and genotype, and has extended consequences for associated organisms and soil processes. A novel litter curling index (LCI) was used to characterize the curling of newly senesced leaves. There are four distinct datasets represented here. 1) A dataset of LCI from 11 plant species (tall annual forb = Helianthus annuus L.; evergreen shrubs = Arctostaphylos pungens Kunth, Quercus turbinella Greene, Rhus ovata S. Watson; deciduous shrubs = Rhus trilobata Nutt., Ribes cereum Douglas, Acer glabrum Torr.; deciduous trees = Elaeagnus angustifolia L., Quercus gambelii Nutt., Populus tremuloides Michx., Populus fremontii S. Watson) mostly growing in natural habitats of Northern Arizona, USA. 2) A dataset containing LCI from two Populus species (P. fremontii James, P. angustifolia S. Watson) and their F1 hyrbids in a common garden in Ogden, UT, USA  (including replicated genotypes of P. angustifolia but not the other tree types). 3) The third dataset examined the relationship between average LCI for a tree and the abundance of agilenid webs under Populus trees growing in a common garden; the LCI values are averages per tree from data collected for dataset 2, and previously published spider web data. 4) The last dataset contains litter and soil moisture values from a litter/soil drying experiment that tested the effect of litter curling on soil moisture dynamics. See the README file for more details on the different datasets.

The new method, termed LCI for litter curling index, is derived by dividing the surface area of a scanned image of a dried curled leaf (LC) by the surface area of a fully flattened image (LF) of the same individual piece of litter (LC/LF). The ratio of curled to flattened litter surface area is then subtracted from 1 (i.e., 1 – (LC/LF)) to create an LCI value that theoretically ranges from 0 to nearly 1, where increasing LCI scores equate to increasing deviation from flatness (i.e., more curled). LCI was measured on a total of 1,757 individual freshly senesced leaves from 176 individual plants, representing 12 species and one hybrid taxon. Spider webs were measured as in Wojtowicz et al. (2014; DOI 10.1007/s00442-014-2998-3). The litter curling experiment was done using leaf litter placed on the surface of pots, watering the pots, then measuring soil and litter moisture over the course of several weeks. The four litter treatments in the drying experiment were naturally flat Populus fremontii, experimental control P. fremontii (naturally flat leaf with a paper clip), experimentally curled P. fremontii (experimentally curled and held with a paper clip), and naturally curled P. angustifolia.

All you need is microsoft excel or an equivalent spreadsheet program.