High Tunnel Exclusion Systems for Improved Pest Management

High Tunnel Exclusion Systems for Improved Pest Management

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Author: Jose Perez, UF/IFAS Small Farms Extension Coordinator

Majumdar_AyanavasmallDr. Ayanava Majumdar is an Extension Entomologist for the Alabama Cooperative Extension System at Auburn University. His work focuses on finding practical solutions for managing insect pests that affect peanut and vegetable crops. “Dr. A,” as he is commonly known, has developed a very strong relationship with growers across Alabama. In recent years, he has gotten a lot of requests from high tunnel growers who are growing vegetables using sustainable agricultural practices. He is an expert in the field of alternative pest management tactics with emphasis on trap crops, pest exclusion, and organic insecticides.

“Protected agriculture has grown in the state for various reasons, especially due to the increasing consumer demand for local foods. Consumers are more aware and want to know who grew the food they consume,” Dr. A said.  Growers are using high tunnels to extend the season during lean times and supply local food to consumers year-round. High tunnels help farmers take advantage of two specific periods. During winters, these structures allow farmers to plant crops earlier than normal and during hot and humid summers, when pests and diseases thrive, they are able to produce crops by regulating temperatures and the amount of rain entering the system.

Protected structures, however, are not exempt from pest problems. “Pest management in high tunnels can be challenging because the diseases and insects take advantage of the growing conditions inside the tunnels,” Dr A said. For example, problems with spider mites and leaffooted bugs have exploded. “These pests really love the heat and the close proximity of plants inside a tunnel. They are very good at exploring their environment and causing rapid crop loss.” he said.

The High Tunnel Exclusion System

Dr. A is pioneering the use of high tunnel pest exclusion systems (HTPE) as a permanent or long-term solution to pest problems. High tunnels are not usually completely closed systems, as the sidewalls and sometimes the ends are open or movable for ventilation purposes. The HTPE technique basically consists of placing a 30-50% shadecloth on these sidewalls under the roll up plastic and at the ends to exclude large insects while allowing beneficial insects to pass through and provide adequate ventilation. This means that the shadecloth material covers about 25% to 33% of the whole structure. The shadecloth is relatively inexpensive and its cost compares well with some expensive organic insecticides. It’s very important to install the shadecloth correctly and seal tightly, otherwise it will not be effective.

ht2Farmers See the Benefits

Dr. A. said that he has seen dramatic reductions in numbers of leaffooted bugs, armyworm moths and other important insect pests as a result of installing an exclusion system. This technique will not exclude all the insects, but the pest pressure overall decreases. “We are currently researching this system in six farms located across the state and this technique has dramatically improved the quality of their crops”, Dr. A said. “We are learning with farmers and have seen that farmers can easily recover the costs within the first season, especially with high value crops such as lettuce or tomatoes,” he said. Dr. A is a believer that his farmer partners are key to validate and spread the technology with other farmers. “After seeing this system work, farmers won’t go back to open high tunnels,” he said. On the other hand, “if farmers don’t like it, they can easily take off the shade cloth and use it elsewhere.”  Dr. A’s research findings are available in the form of videos and publications on the Alabama Vegetable IPM website.

IMG_5115smallOrganic and Alternative Systems

Dr. A is looking at providing solutions for organic and alternative systems. “Customers are asking what the farmers are spraying. The growers have to be more responsible since they are talking to very aware customers.” As a result, he has seen small farmers spending a lot of money using insecticides approved for organic production.  The exclusion technology will help, but it’s not a silver bullet. Dr. A is currently studying the release of beneficial insects in these systems. “Pest prevention is the goal in organic systems. Once the pest is there, there are very few tools you can use,” he said.

Learn from Dr. A

Dr. A. will be a speaker at the Panhandle Fruit and Vegetable Conference on October 11 in Marianna, FL. He will teach two different Integrated Pest Management (IPM) workshops. The first one will be focused on open field conventional vegetable production. The second workshop will focus on organic alternative IPM systems using the Pest Exclusion system. During the event, he will be providing free copies of the High Tunnel Crop Production Manual for New and Beginning Farmers and the Alternative Vegetable IPM Slide Chart and insect scouting guides. Don’t miss the talks!

Pandhandle SFC2To register and find out more information about the conference visit: https://pfvc.eventbrite.com. Early bird registration is $40 and ends September 5. Your registration includes breakfast, lunch, refreshments, educational materials and transportation to farm tour locations. The event is sponsored by UF/IFAS Extension and support in part by a Florida Department of Agriculture Specialty Crop Block Grant.


Satsumas Return to North Florida

Satsumas Return to North Florida


Author: Jose Perez, UF/IFAS Small Farms Extension Coordinator

Tour a Satsuma Grove on October 11

There was a time when citrus production was booming in North Florida. In the 1920’s, Jackson County, Florida, was known as the Satsuma capital of the World. Satsuma is a citrus variety with excellent eating quality that is cold heady and matures early. Back then, there were about 3,000 acres of satsumas growing in the region, and the town of Marianna organized yearly satsuma festivals. That all changed in 1935 when hard freezes devastated the industry by killing the trees. The satsumas did not come back, and producers turned to other crops for income.


Mack Glass

Satsumas were missing from the North Florida landscape until farmer-pioneer Mack Glass became interested in this crop as a way to diversify his farm. Federal payments for agronomic crops started to slide in the 1990’s and the time was right to look for alternative crops. In 1999, Mack attended an agricultural summit where the take-away message was, you either become a mega farm or you pursue niche production. “I decided to pursue a niche product,” said Mack, who decided to plant 6 acres of satsuma mandarins in the year 2002 with the help of UF/IFAS faculty. Along with two other farmer friends, they formed the Cherokee Citrus Cooperative. Mack estimates that there are now about 30 acres of satsumas growing in the region.

Innovative Freeze Protection

Freezing temperatures destroyed the industry in the 1930’s and according to Mack, it continues to be the major threat to the industry. However, one of the main factors that convinced him to give satsumas a try was a micro-irrigation technology that could help the trees withstand the hard freezes in North Florida. The freeze protection system works because heat is released when water turns into ice. The ice protects the tree and allow them to survive.

In January 2003, a year after he had planted the satsuma trees, his grove passed its biggest test to date. The temperature was 15 degrees, but thanks to the micro-emitters, he only lost one tree. “Some years we haven’t used the frost protection irrigation at all, like last year. On the other hand, there was a year where we had to use it three days straight,” he said.


Mack’s satsuma grove

Interest in Growing Satsumas Is Increasing

There are a few more growers planting satsumas in the region, which is encouraging said Mack. “The more growers we have, the better.” Mack is not shy about sharing his experiences with others and encouraging them to plant satsumas.” I think the acreage of satsumas will continue to grow in the future, he said. Besides the threat of freezes, problems with labor availability is an important factor that makes many growers think twice about planting satsumas.

Citrus greening has not been a concern in this part of the state, and Mack reported that no disease had been detected. The low winter temperatures in the region help break the lifecycle of the Asian citrus psyllid, the vector that transmits citrus greening.

Satsumas for Lunch

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Mack visiting Santa Rosa County schools

There was no market for satsumas, but Mack and his fellow farmers have worked hard to put satsumas in the region’s school lunch menus. “I introduced Mr. Glass to Santa Rosa County’s Sodexo manager and they are now serving his satsumas for the county’s schools,” said Christina Walmer, a Food Systems Coordinator for the Farm to School, Farm to Community FNP-UF/IFAS Program. “We did whatever was needed to serve this market. We got insurance, food safety certification, and worked with Fresh From Florida to make this happen, we are fortunate” said Mack.  “Even when satsumas are part of the school lunches for only November and December, they have become the favorite item for many children” Mack often goes to schools and shares with students the history of satsumas and how this locally grown fruit is coming back. Some fruit is also sold through organizational fundraising events.

Mack was one of the first producers in Jackson County to become GAP (good agricultural practice) trained in food safety. Mack has now built a USDA approved citrus packing facility, and is hoping to join forces with more growers in the future.

Visit Mack’s Satsuma Grove on October 11

The Panhandle Fruit & Vegetable Conference is scheduled for October 11, 2016 in Marianna, FL. The event will give participants the chance to tour Mack’s grove through an afternoon farm tour. By that date, everyone will be able to see fruit beginning to turn color. Mack will lead a tour of his grove showing various aspects of his operation, including how the freeze protection works.  The conference will also offer a Protected Agriculture tour, practical workshops, conference sessions, and a trade show. A highlight of the event will be farmer and author Richard Wiswall as the Conference Keynote Speaker.

For more information and registration visit: https://pfvc.eventbrite.com. Early bird registration is $40 before September 6. Your registration includes breakfast, lunch, refreshments, educational materials and transportation to farm tour locations. The event is sponsored by UF/IFAS Extension with support in part by a Florida Department of Agriculture Specialty Crop Block Grant. We look forward to seeing you there!