GROWING TOMATOES WITH LESS TILLAGE
Jeff Mitchell University of California, Davis
Since 1999, we have evaluated conservation tillage (CT) and cover cropping (CC) practices for tomato production in an 8 acre field in Five Points, CA. The objective of this work have been to compare standard till (ST) with and without (NO) winter cover crops and conservation tillage with and without cover crops in terms of economics, productivity, soil properties and dust emissions through a tomato – cotton rotation. The study field is divided in half to allow both crops to be grown in each year. A summary of the first five years of this work is presented here.
stalk management operation and are “re- readied” using furrow sweeps at the time of transplanting and during in-season cultivations. In the CT cover crop systems,
Chopping triticale/rye/vetch cover crop using Buffalo Rolling Stalk Chopper in Five Points, CA conservation tillage study, 2005.
The standard tillage systems have been managed as is customarily done in the West Side San Joaquin Valley region. Beds are disked and reformed following harvest of each crop. Prior to tomatoes, the beds are also shaped with a power incorporator. The standard till cover crop system uses a triticale/rye/vetch “green manure” approach with the cover crop disked in each spring before establishing the summer crops.
The CT systems use about 50% of the overall tillage, or soil disturbance operations as the ST systems. Tomatoes are “no-till” transplanted and cotton is no-till seeded into beds that haven’t been worked or moved since the beginning of the study, - except for a shallow cotton root undercutting following harvest for Pink Bollworm management compliance. Tomato beds have been quite “rough” following the one-pass fall cotton
Transplanting processing tomatoes into cover crop and cotton residue (left) and cotton residue (right) in Five Points, CA conservation tillage study, 2004.