A steady decline in cotton acreage in the Imperial Valley from 140,000 acres twenty years ago to a little over 4,000 acres in 1992 is cause for concern. We believed that plant mapping could help the Imperial Valley growers improve their production. Our objectives in surveying thirty cotton fields were threefold: 1) demonstrate the validity (or lack thereof) of the UC programs in a location other than the San Joaquin; 2) create a database specifically for the Imperial Valley; 3) pinpoint any management practices that could be changed to make cotton more profitable again.

Height to node ratios from the Imperial Valley followed the same pattern, but were slightly lower than those for the San Joaquin fields. Nodes above white flower values from Imperial followed the same relationship to days after first flower as the San Joaquin fields. Both of these in-season monitoring parameters indicated early season stress played a role in the Imperial Valley.