Long-Term Ecological Research (LTER)/KBS004: Kellogg Biological Station Main Cropping System Experiment

Cropping systems were established in spring 1988: 1) standard chemical input corn/soybean rotation conventionally tilled; 2) standard chemical input corn/soybean rotation no-tilled; 3) low chemical input corn/ soybean/wheat rotation ridge tilled; 4) zero chemical input corn/soybean/wheat rotation ridge-tilled; 5) Populus clones on short-rotation (4 year) harvest cycle; 6) continuous alfalfa; 7) early successional community on historically tilled soil; 8) early successional community on never-tilled soil.

Systems 1-7 are installed in 0.9 ha plots in each of six replicate 5-ha blocks; system 8 is replicated in four 0.06-ha plots 200 m off-site on the same soil series. For each cropping system (and for a number of microplot treatments nested within the main treatment plots) the following baseline variates are being measured (some are described in greater detail in other data set descriptions): 1) plant characteristics, including species distributions and abundances, net aboveground productivity by functional group (crop vs. weeds, selected weed species), economic yields, tissue C and N contents, seed bank composition, root biomass at physiological maturity; 2) soil chemical and physical characteristics, including soil moisture, pH, inorganic N and P pools, total C, N, and P pools, bulk density; 3) soil biological characteristics, including microbial biomass C and N, N mineralization rates (buried bags), fungal/bacterial ratios, invertebrate populations, fungistasis; and 4) insect and pathogen dynamics, including distributions and abundances of major insect pests and predators and of Fusarium pathogens.