Crop rotation information for  "Data on the effects of crop rotational diversity and nitrogen fertilisation on cereal yields" https://doi.org/10.5878/8af1-0q60. 
Cropping sequence of all crop rotations per site (see Supplementary Table 1 for site name and information) whereby '-' indicates a shift in time (usually a year) when the next crop is grown, '+' indicates multiple crop species grown together in the same field and '/' indicates that the two crops either side are grown in alternate years. Mean yield and standard errors refer to the long-term raw yield mean of each indicator crop per rotation and per external N input level for the period to which the yield data refer (see Supplementary Table 1 data years). Yields are based on 100 % dry weight. Mean yields were calculated regardless of management (except N input), therefore could include yields from different tillage. The number of observations relates to yield observations in our dataset for each indicator crop per rotation and per external N input level. Note that some rotations will have observations for more than one indicator crop. Also listed are the CRD metrics, species diversity (SD; based on the inverse Simpson's diversity index) and functional richness (FR; the number of functional groups included in the rotation) and a list of the specific functional groups present in the rotation (whereby, C = cereal, B = broadleaf, Ley = ley and LEG = legume). Crop abbreviations are as follows: A = alfalfa, Be = beans, B = barley (phenology not known), C = canola, CP = chickpea, F= fallow, FB = fava bean, L = ley, Lg = legume (specific species changed over the years), M = maize, Mi = millet, O = oats, OSR = oilseed rape, Pe = pea, Po = potato, R = rye, RC = red clover, S = soy, Saff = safflower, SB = spring barley, SF = sunflower, Sg = sorghum, SuB = sugarbeet, SW = spring wheat, Swe = swede, Ti = timothy, US = the following crop was undersown with the previous crop, V = vetch, W = wheat (phenology not known), WB = winter barley, WR = winter rye, WT = winter triticale, WW = winter wheat.

Please see the file Crop_rotational_information.tsv for the table with crop rotation information.