The Florida legislature passed the 1999 Florida Watershed Restoration Act that gives the Florida Department of Agriculture and Consumer Services the authority to develop interim measures. They include best management practices or BMPs, cost-share incentives and other technical assistance programs to assist agriculture in protecting our water resources.
By definition, BMPs are a practice or combination of practices, based on research, field-testing and expert review, to be the most effective and practicable on-location means to reduce potential nutrient contamination of surface and ground waters. The BMPs includes economic and technological considerations, growers can implement with a minimum impact on production.
In 2013 University of Florida, Institute of Food and Agricultural Sciences researchers, specialists and Extension agents created 10 BMP watershed teams to address the water quality and quantity issues that the agricultural industry is facing. Educational programs were developed to cover topics including irrigation efficiencies, nutrient application and efficiencies, soil testing, conservation techniques, runoff reduction, etc.
Seminars, field days, workshops and demonstrations have been conducted to assist the 44,000 commercial farmers who produce food, fiber, and livestock on approximately 10 million acres in Florida to better understand and adopt BMPs.
A website (http://bmp.ifas.ufl.edu/) has also been improved to provide meeting schedules, presentations, published works and other information to allow growers to make informed choices.
UF/IFAS research has demonstrated that water and fertilizer management are inextricably linked. Changes to one will almost inevitably affect the efficiency of the other.
The goal of proper water management is to keep both the irrigation water and the fertilizer in the root zone. Fertilizer and the energy to run irrigation systems are significant costs of production and through education growers are learning that besides benefitting the environment the adoption of BMPs can contribute significant savings to their operations while maintaining high yields.
The following are a few stories to illustrate the impact and successes of the BMP watershed teams.
Increasing irrigation efficiency in North Florida
North Florida’s Lower Suwannee River Basin is a major field crop production area, particularly for corn and peanuts. Supplemental watering is required to achieve maximum economic production due to sandy, porous soils.
More than 100,000 acres of agricultural land in the basin have been fitted with overhead irrigation systems to meet water demand and achieve economic optimum production. The Suwannee River Water Management District reports that on average, production agriculture withdraws 180 million gallons of water per day. More than 2,000 center-pivot irrigation systems in the Suwanee River Basin account for most of the consumption by agriculture.
Continuously measuring soil moisture and climate data using current, affordable technology is an excellent method to optimize irrigation management, increasing economic and environmental sustainability. Measuring systems are automated and relatively maintenance free.
However, gaps exist in both technical and agronomic knowledge which reduces on-farm implementation of the technology.
IFAS Extension agent Mace Bauer developed a project that assembled equipment into a package that could be readily adopted by farmers.
Field sensor kits were put together using commercially available components including a fiberglass enclosure mounted on a pole, datalogger, cell phone modem and antenna, 12-volt battery, solar panel, tipping bucket rain gauge and a soil moisture sensor.
Fifteen sites spread over several counties and multiple farmers were equipped with the package at their own expense. The Extension agent familiarized the growers with the user interface and irrigation management basics including soil water holding capacity, evapotranspiration and allowable water depletion.
Farmers willingly adopted and used the technology. One farmer reported eliminating four 1-inch irrigations on 180 acres. This resulted in water savings of 19 million gallons and reduced pumping costs by about $5,000.
Vegetable growers install drip irrigation in Southwest Florida
According to a survey by Gene McAvoy, a multi-county vegetable Extension agent and county Extension director in Southwest Florida, vegetable growers are installing drip irrigation at an increased pace.
Over the past five years, adoption of more efficient low-volume drip irrigation systems by vegetable growers has increased dramatically in Southwest Florida from approximately 35 percent of the total acreage to more than 65 percent of the total acreage, converting from traditional seepage irrigation systems to more efficient drip irrigation systems.
This change to drip has the potential to reduce water consumption by nearly 2 billion gallons per week. Educational programs are being developed to help growers learn how to efficiently manage these drip systems.
Fertilizer banding in potato production
Potatoes grown in the Tri-County Agricultural Area of North Florida have traditionally been fertilized by pre-plant incorporated broadcast applications.
This practice tends to waste fertilizer because nutrients invariable find their way into the water furrows and ends of the fields where potatoes will not be grown.
Over the past few years, IFAS on-farm research has demonstrated the uniformity and value of banding fertilizer into each row of potatoes.
Banding increases the fertilizer use efficiency and allows growers to reduce the amount of fertilizer that is applied to a field for crop use.
Combined with not fertilizing field edges and water furrows, fertilizer applications have been reduced by about 25 percent.
The technology has had overwhelming adoption rates with more than 30 percent—6,000 acres—of the potato acreage converting from broadcast to banding.
This trend is expected to continue over the next few years. The concept of banding instead of broadcasting fertilizer is also spreading to other area vegetable producers, including those growing cabbage and leafy greens.
Dr. Kelly Morgan is an associate professor of soil and water sciences at the Southwest Florida Research and Education Center in Immokalee. He can be reached at email@example.com. Stewart Swanson is a consultant on the BMP Project.
There’s more to come. Watch for the August issue of Citrus + Vegetable Magazine, which will have more BMP success stories.