Micro-Sprinklers in Strawberry Production Saves Water

Research study conducted in partnership with RDO Water Strawberry-Micro-Sprinkler

Author: RDO Water

In October 2014, a 10-month research study began on the use of micro-sprinklers in strawberry production. RDO Water was a key participant in the study, conducted at Manzanita Berry Farms in Santa Maria, CA, in partnership with University of California Agriculture and Natural Resources Cooperative Extension.

RDO Water released its results and analysis of the study in January of this year. Earlier this month, UC published a story specific to the water-savings discovered in the study, as included below.

The Issue
Water is an important resource for growing plants, and it has become scarce due to epic drought conditions in California. Conserving water through improved irrigation practices is critical for maintaining acreage of a lucrative commodity such as strawberry. Strawberry growers typically provide supplemental irrigation through overhead aluminum sprinklers to mitigate the dry conditions of the region. However, they can be inefficient systems, because they require a significant amount of water, and because there is plastic mulch on the beds, which limits the water that enters the soil and increases runoff potential. Micro-sprinklers, commonly used in orchard systems, could offer an efficient alternative to conventional aluminum sprinklers.

What Has ANR Done?
A study was conducted at Manzanita Berry Farms in Santa Maria during the 2014–2015 production season to evaluate the potential of micro-sprinklers in strawberry production. The study compared conventional aluminum sprinklers with micro-sprinklers on about one hundred and twenty 330-foot-long strawberry beds. Data were collected on the amount of water distributed, electrical conductivity of soil that determines salt condition, strawberry yield, and the incidence and severity of powdery mildew and botrytis fruit rot. While there were no conclusive findings about diseases, there were significant water savings without a negative impact on fruit yield. Detailed information about the study design and findings can be found at: http://ucanr.edu/blogs/blogcorepostdetail.cfm?postnum=19699.

The Payoff
Significant water savings without additional maintenance costs.
This study demonstrated 32% water savings in just 3 weeks of using the micro-sprinkler system. This new information can inform future growing practices for this important California crop, valued at $2.2 billion. An initial estimate by a vendor suggests that equipment and handling costs of the micro-sprinklers are more or less similar to those of the aluminum sprinklers. If adopted, strawberry growers could conserve resources without incurring additional maintenance costs or experiencing any changes to strawberry yield.

 

To learn more about micro-sprinklers, contact Danilu Ramirez at dramirez@rdowater or a local  RDO Water store. The full list of RDO Water’s eight locations in Arizona and California can be found at http://rdowater.com/contact.

 

Full article shared from UC Delivers, with credit to Dr. Surendra Dara.

RDO Water Releases Micro-Sprinkler Study Results

The benefits of micro-sprinkler irrigation for strawberry growers
Author: Danilu Ramirez, CCA, PCA, RDO Water RDO-Water-Micro-Sprinkler

Beginning in October of 2014, RDO Water participated in a 10-month research study with the University of California Agriculture and Natural Resources Cooperative Extension to evaluate the potential of micro-sprinklers in strawberry production. The study was conducted at Manzanita Berry Farms in Santa Maria, CA.

Study Overview
To begin the study, a block of strawberry was divided into two parts:
• East half set up with grower-standard solid-set aluminum pipe sprinkler irrigation design for establishment
• West half set up with a micro-sprinkler irrigation design throughout the season

Each block was planted on Nov 6, 2014. Prior to planting, drip tape was installed in the beds and was the main method of irrigation throughout the duration of the study, the 2014-15 growing season.

Research was conducted periodically throughout the growing season. Upon conclusion of the study, results were compiled and shared by Surendra Dara, PhD, DAIT, Strawberry and Vegetable Crops Advisor and Affiliated IPM Advisor for UC Cooperative Extension. Read the complete report in his blog post.

Below is a summary of key takeaways and primary benefits of the micro-sprinkler irrigated field in four primary areas:
Water Savings; Energy and Labor Efficiency; Disease and Pest Control; Pesticide Reduction

Additional Note: Both fields produced an overall healthy crop comparable in total marketable yield.

Water Savings
Study Summary: Micro-sprinklers reduced total water usage and applied it more efficiently.

Reduced water usage during establishment
• Approximately 32% of water savings in just three weeks compared to solid-set aluminum pipe
• Micro-sprinklers delivered 81,600 gallons of water per acre during establishment vs 120,000 gallons of water per acre for aluminum pipe
• Micro-sprinklers saved nearly 40,000 gallons of water per acre during establishment

Efficient water application
• Micro-sprinklers apply water in a smaller droplet size that doesn’t bounce off plastic mulch
• More water goes directly to the plant
• Less run-off
o *Added benefit of reduced nitrate loading risk, potential to reduce Waterboard requirements

Energy and Labor Efficiency
Study Summary: Micro-sprinklers demonstrated significant energy and labor savings.

Efficient by design
*Micro-sprinkler irrigation systems don’t require constantly moving cumbersome aluminum pipe
• No pipe for crews to navigate during harvest, weeding, etc.; low-profile micros do not get in the way
• No pipe to move when tractors are in the field spraying, cultivating, etc.

Energy savings
• Low pressure system: Only 30 psi needed to deliver water through the system
• Typically better Distribution Uniformity compared to aluminum pipe

Efficient crop production
*Micro-sprinklers produced less unmarketable fruit
• Plant energy goes into producing good fruit
• Saved money, time and energy from harvesting unprofitable product
• Better conditions for crews, faster moving through the field, less time spent cleaning plants

Additional Notes: Marketable berry yield data was collected two to three times per week, from February 7 through June 12. The micro-sprinklers produced nearly 1,500 fewer unmarketable berries per plot while keeping up with total yield compared to the standard aluminum pipe sprinkler block.

Disease and Pest Control
Study Summary: A common misconception is that micro-sprinklers promote disease; on the contrary, they suppress it. They also create an ideal environment to control pests like spider mites, and foster good beneficial insect populations.

Disease Control
*Powdery mildew severity was tested twice, in April and again in June
• Both tests showed significantly less mildew in micro-sprinklers

*Botrytis fruit rot was tested once per month in March, April, May and June.
• Micro-sprinklers showed less severe Botrytis fruit rot initially
• A significant difference was seen three days after harvest samples were collected
• In Micros: Easy to visually see much less rotten fruit being culled and thrown into the furrows

Pest Control
*Micro-sprinklers create a humid environment
• Spider mite webbing cannot form in high humidity
• Mites cannot thrive due to lack of dusty conditions, micros fine mist keeps dust off leaves
• Water stress prevention helps suppress populations of two spotted spider mites and boosts overall plant health
• Fosters good beneficial insect growth – less money is spent on releasing and establishing Persimilis as they thrive in humid conditions
• High humidity is needed to ensure Persimilis egg hatch

Pesticide Reduction
Study Summary: Micro-sprinklers offer more efficient and safe pesticide control, as well as the option for pesticide-free control.

Humidity Control
*As mentioned earlier, micro-sprinklers create a humid environment, not conducive to spider mite growth, allowing pest control via water vs. traditional pesticides
• High humidity environment is created by running micros at frequent short intervals per field conditions
• Use of humidity is environmentally sustainable and does not contribute to pesticide resistance as do conventional miticide sprays
• Humidity can be used as an organic method of spider mite control or as an aid in a conventional system
• As humidity strengthens persimilis counts, they also work to control spider mite hot spots

Pesticide Application
*Direct application of several types of pesticides via chemigation through the system
• More efficient, safe application
• Eliminates need for helicopter sprays; rainy winters, when furrows are too muddy for tractors to spray, micros can be used as a foliar applicator
• Per labels, fungicides, pesticides and fertilizers can be applied via micros as a foliar spray

Overall Study Summary
Micro-sprinklers have a long list of benefits that have been proven to be statistically significant through RDO Water’s trial work with the UC Extension. Water and energy savings during establishment are of high importance as the drought continues to affect California growers. Using a low pressure energy efficient system that saves more than 30 percent water and concurrently helps reduce pesticide use while promoting beneficial insect populations might sound too good to be true but it’s a reality. Labor savings, disease suppression, and less unmarketable fruit include even more benefits. Micro sprinklers are influencing strawberry growing practices now and will continue to make an impact in the years to come.

About The Author
Danilu Ramirez, CCA, PCA is a Water Quality Consultant for RDO Water, based in Santa Maria, CA. Contact her at 805.345.5418 or dramirez@rdowater.com.