OPEN ALL® FIELD TRIAL AT
UNIVERSITY OF CALIFORNIA SOUTH COAST R.E.C.

Kirk D. Larson, Department of Promology
University of California, Davis/South Coast REC, Irvine

OPEN ALL® is a soil amendment containing sulfuric acid and other materials. It is marketed as a soil conditioner for: 1) improving soil structure and aeration; 2) normalizing saline or alkaline soils; 3) neutralizing soil pH; and 4) increasing nutrient availability to the plant. In 1993, the distributors of OPEN ALL® funded a field trial at the U.C. South Coast Research and Extension Center to test the effectiveness of this product for enhancing strawberry production under Southern California conditions.

OPEN ALL® was applied as per label directions (20:1 H20:OPEN ALL®, with one gallon of OPEN ALL® per 1,000 sq. ft.) on 3 September, 1993. The material was applied to four plots, each measuring 15' x 5.7', in a single 4-row strawberry bed (68" center) at the U.C. South Coast R.E.C. Four identical plots in the same bed were left untreated (control). After applying OPEN ALL®, approximately eight acres-inches of water were applied as per label instructions to the entire bed using micro-sprinklers. Fertilizer and drip irrigation tubing were placed in the beds in mid-October, and 40 plants of the strawberry cultivar 'Chandler" were planted in each plot on 1 November, 1993. Plants were spaced 16" apart in the row for an equivalent of 23,061 plants per acre.

 Fruit harvest began 8 February. Yield data were collected from 8 February through 28 June, 1994, for a total of 24 harvests. Fruit were harvested weekly or twice weekly, and yield, mean fruit size, fruit appearance, and fruit firmness were determined for each plot for each harvest. Fruit yield size, appearance and firmness were determined for the entire harvest season, as well as for the respective monthly intervals. Yield data are presented below:

These results indicate that OPEN ALL® can increase yields of 'Chandler' strawberry under Southern California conditions. However, the higher yields obtained with OPEN ALL® must be weighed against the cost of the material, and the cost of eight acre-inches or irrigation water. Additional studies, using earlier planting dates, various soil types, and other acidic or acid-forming soil amendments, are needed to more fully assess the effectiveness of OPEN ALL®.