Selecting cover crops for hillside experiments in Bolivia.
The mid-elevation hillsides of the Cochabamba region of Bolivia between 2,500 and 4,000 m asl are characterized by a multitude of microclimates for crop production. Poor productivity of food crops in the Cochabamba region has been associated principally with declining soil fertility. The time for natural fallow has declined steadily as more land for crop production is required. The use of legume cover crops, therefore, to improve the restoration of soil fertility during the brief natural fallow period offers considerable possibilities for improvement. Potential legume cover crops were identified that can germinate, flower, and set seed within the possible growing season constrained by temperature, photoperiod, and rainfall patterns. A photothermal model was calibrated for each of twelve cover crops. Simulations were run using the climate records for three hillside sites near Cochabamba. Six of the more temperate cover crops investigated could mature and provide seed from any sowing date at 2,600 m, and from most sowings at 3,220 m, but few were adapted to 3,490 m. Potential cover crops, not currently grown locally, and adapted for this cropping system, were identified and recommended for further field trials.
Wheeler, T.R., Qi, A., Keatinge, J.D.H., Ellis, R.H. and Summerfield, R.J. 1999. Selecting cover crops for hillside experiments in Bolivia. Mountain Research and Development, 19(4): 318-324.