Table 1.

Management histories and fertilization applications for the soils from the LTER plots at the KBSa

TreatmentVegetationNitrogen applicationVariants
1Corn, soybean, and wheat rotationAmmonium nitrate at 124 kg of N ha−1 for corn and 84 kg of N ha−1 for wheatFertilized vs nonfertilized
2 (no tilling)Corn, soybean, and wheat rotationAmmonium nitrate at 124 kg of N ha−1 for corn and 84 kg of N ha−1 for wheatFertilized vs nonfertilized
5Perennial PopulustreesNoneNone
7
 FertilizedSuccessional since 1989120 kg ha−1 annuallyTilled vs not tilled
 NonfertilizedSuccessional since 1989NoneTilled vs not tilled
NDFNative deciduous forestNoneNone
  • a Treatments 1 and 2 reflect highly cultivated agricultural soils, while treatment 7 demonstrates a change in plant community to successional grassland following 40 years of intensive cultivation. Variants were drawn from microplots within the larger treatments which were left unfertilized (treatments 1 and 2) or were not tilled (treatment 7). Treatment 5 has a perennial cover crop of Populus trees. Additional information on LTER plots is available at http://www.lter.kbs.msu.edu.