You are here: Home / About / The Century Experiment

The Century Experiment

by admin last modified Sep 28, 2015 04:47 PM

The Century Experiment is located on the main plots at the Russell Ranch Sustainable Agriculture Facility. The Century Experiment measures the long-term impacts of crop rotation, farming systems and inputs of water and nitrogen on agricultural sustainability. The cropping systems in the long-term experiment include rainfed and irrigated systems, organic and conventional systems, and different forms and quantity of nitrogen inputs. The study began in 1993 with a uniform sudangrass crop to evaluate inherent soil differences and the original cropping systems were first planted in Russell Ranch Century Experiment Design - as of May 20151994.

Current experimental design

The cropping systems at the Century Experiment are designed to fall along a gradient of increasing irrigation and fertilization intensity. Currently, the Century Experiment contains ten systems that are two-year rotations and include corn/tomato, wheat/tomato, wheat/fallow and wheat/legume rotations. Additionally, a perennial native grass system and a 6-year alfalfa-corn-tomato rotation were initiated in 2012. There are six one-acre plots per system, three plots for each of the two phases. Each plot also contains 40 micro-plots which allow scientists to test hypotheses on a short-term basis. These micro-plots are outside of the yield measuring area, which is used for long-term data collection.



Changes in cropping systems

The cropping systems of the long-term project are being evaluated to be more flexible and responsive to current trends, while maintaining the integrity of the long-term experiment. Long-term experiments are dynamic and need to respond to changing farming practices, as well as address evolving scientific priorities. Additional new projects being discussed include: integrated nutrient management systems, animal forage systems, woody perennials (orchards and vineyards), reduced tillage rotations and restoration ecology.

Original Experimental Design 


 Changes in cropping systems since 1993:

  • In 1999, a new transitional system (indicated by **) was added which converted conventional plots to an organic corn/tomato rotation (see Elizabeth Martini's paper here)
  • In 2003, SAFS moved to the Century Experiment. The Legume-Corn-Tomato system was altered to receive cover crop each winter (instead of every other winter).
  • From 2003-2007, all one-acre plots of the tomato/corn systems were split in half and reduced tillage treatments were compared to standard tillage treatments (see tillage results here)
  • In 2007, Irrigated Wheat/Legume was discontinued (indicated by †)
  • Wheat replaced corn from 2010-2012 (indicated by a * in the current cropping system table)
  • In 2012, two systems, a six-year rotation (alfalfa-tomato-corn) and perennial native grasses, were added to the Century Experiment 



Event Details

In This Section

Links in this section


One Shields Drive
UC Davis
Davis, CA

(530) 752-3915