USA: Sustainable Agricultural Practices at Dole Fresh Vegetables

To employ the most eco-friendly practices, Dole strives to control its fertilizer use and pesticide consumption in the production of fresh vegetables.

Fertilizer Use Control

Dole Fresh Vegetables (DFV) has implemented several initiatives to help limit the use of fertilizers in its Californian berry operations.

First and foremost, every three weeks DFV takes tissue samples of its crops for in-depth analyses. The results reveal existing levels of nitrogen (N), phosphorus (P), potassium (K) and micronutrients, which enable farmers to apply appropriate quantities of nutrients and avoid over-use.

Additionally, DFV carries out a three-step soil solution analysis that gauges the penetration levels of applied fertilizers.

Step 1: Prepping and Installing the Tubes

Prepping the soil solution tubes, which have ceramic tips for water entry, and then installing the tubes at various depths to determine penetration levels of applied fertilizer.

Step 2: Obtaining Soil Samples

A vacuum is pulled to simulate water and nutrient intake by the plants’ roots. A day or two later, the solution is extracted from the tubes for analysis.

Step 3: Results

The results provide growers with an accounting of where the fertilizers end up. We also use soil moisture sensors at various depths to help evaluate irrigation practices.

Integrated Pest Management (IPM)

Dole implements a detailed scouting program that integrates cultural and biological control measures to manage pests in the fields. These alternative methods are subject to rigorous evaluation to ensure that they offer a responsible and sustainable solution to the problem. Conventional crop protection products are used as a last resort and in the smallest possible quantities that will rid the area of pests. The scouting program follows three steps to ensure maximum pest management.

Step 1: Weekly Field Examinations

A worker examines the leaves for evidence of insect presence. These field scouts are performed on a weekly basis in order to discover  both beneficial and destructive insects among the crops.

Step 2: Scouting Report

Scouting reports divide the fields into 5-10 acre blocks. For each block, the report includes the average number of beneficial and destructive insects.

Step 3: Release of Predator Mites

Based on data in the scouting reports, predator mites are released into the fields as a way to biologically control destructive pests. For example, the two-spotted mite, a destructive insect, is controlled by the persimilis, a predator insect.

The “home base” of the ICM Program is at DFV’s scouting program facility in Watsonville, CA, where predator mites are raised.

Additional Methods for Pest Control

To safely control the lygus population in the fields, DFV employs bug vacuums instead of insecticides. Not only are lygus adults are difficult to control with insecticides, but using such chemicals will kill the beneficial mites, therefore eliminating the biological measures taken for pest management.

DFV also uses electrostatic sprayers, which target the leaves more effectively than traditional sprayers and allow us to reduce pesticide use up to 50%.