| RecYear | | Physical quantity | Year of sample collection |
| RecMonth | | Physical quantity | Month of sample collection |
| RecDay | | Physical quantity | Day of sample collection |
| Plot | | Physical quantity | Plot designation in 2017, after irrigation lines were shifted |
| Current | | Nominal | Treatment in 2017, after irrigation lines were shifted |
| Historic | | Nominal | Previous treatment (1991-2016) |
| Position | | Nominal | Landscape position in the upland or lowland |
| Replicate | | Nominal | Irrigation line: (A) started in 1991, (B) started in 1993 |
| Replicate_ed | | Nominal | Irrigation lines as in "Replicate", but divided into uplands and lowlands to yield spatial "blocks" |
| timept | | Physical quantity | Timepoint of data collection (1-6) |
| daysburied | | Physical quantity | Number of days bags were buried |
| yearburied | | Physical quantity | Number of years bags were buried |
| ovendry_wt | | Physical quantity | Mass of remaining litter in grams |
| ovendry_wt_adj | | Physical quantity | Mass of remaining litter in grams, adjusted for soil contamination using the equations in the main text and in Norris et al. 2001 |
| prop_bag_litter | | Physical quantity | Proportion of bag weight that is litter, not soil, calculated using the equations in the main text and in Norris et al. 2001 |
| mass_remain | | Physical quantity | Proportion of litter remaining (using adjusted oven dry weight) |
| carbon | | Physical quantity | Carbon concentration of remaining litter (%) |
| nitrogen | | Physical quantity | Nitrogen concentration of litter (%) |
| nitrogen_adj | | Physical quantity | Nitrogen concentration of litter (%), adjusted for soil contamination using the equations in the main text and in Norris et al. 2001 |
| cnratio | | Physical quantity | Carbon concentration / nitrogen concentration (adjusted) |
| N_mass_remain | | Physical quantity | Percent of N from original bags remaining, calculated using the N concentrations of initial litter and remaining litter |
| comments | | Nominal | Notes about collected bags, especially if there was a visible layer of fungi on the litter. |
