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  • Mulch Improves Water Conservation in Vegetable Production

    Sweet onions are shown growing in Tifton, Georgia, with two types of mulch: organic (wheat straw mulch) on the left and inorganic (plastic mulch film) on the right.

    By Juan Carlos Díaz-Pérez

    For centuries, horticulturists have modified the crop microenvironment to extend the production season and enhance crop growth, yield and quality. Some of the techniques to achieve environmental modification include the use of mulches, high tunnels, greenhouses, etc.

    Mulches are widely used in both conventional and organic vegetable production. According to Wikipedia, “a mulch is a layer of material applied to the surface of soil with the goal of conserving soil moisture, improving fertility and health of the soil, and reducing weed growth.”

    Mulch may be organic (straw, leaves, cover crop residue, newspaper, wood chips, etc.) or inorganic, such as plastic film. Mulch effects on crops may vary depending on different factors.

    Factors affecting organic mulches include source of organic material (plant or animal), size of the particle, thickness of the mulch (amount applied) and age of the material. Factors affecting plastic mulch films include color, thickness, composition and permeability.

    In a vegetable crop field, soil water may be: 1) evaporated from the soil, 2) evaporated from the surface of the leaves of the crop, in a process called transpiration, 3) lost from surface runoff or 4) lost by percolation. In this article, we will focus on ways to improve soil water conservation.

    SOIL WATER EVAPORATION

    Both organic mulches and plastic mulch films act as barriers to water evaporation from the soil. These two types of mulches differ, however, in how they diminish soil water evaporation.

    In bare soil, water tends to evaporate from the soil. Soil water evaporation is proportional to the evaporative demand. Evaporation increases with increasing air and soil temperatures and decreasing relative humidity.  The rate of soil water evaporation also decreases as the soil water content decreases.

    According to the Food and Agriculture Organization of the United Nations, organic mulches may reduce soil water evaporation from 40 to 90 percent relative to bare soil. A thickness of 2 to 4 inches is effective in reducing evaporation. Soil evaporation tends to decrease with decreasing particle size of organic residues.


    Plastic mulch films are, in general, more effective in reducing soil water evaporation compared to organic mulches. Plastic mulch films differ in permeability to gases due to differences in film composition. For example, virtually impermeable film and totally impermeable film provide greater fumigant retention compared to low-density and high-density polyethylene film. With respect to soil evaporation, however, all plastic mulch films seem to be effective in conserving soil moisture.

    Physical damage or deterioration decrease the effectiveness of a plastic film to reduce soil water evaporation. Biodegradable mulches may be more prone to rapid deterioration compared to plastic mulch films.

    RAINFALL PENETRATION INTO SOIL

    Water-use efficiency increases when the crop uses rainfall water. Although organic mulches reduce soil evaporation, they allow for water penetration to the soil after a rainfall event. In fact, by reducing water flow through the soil surface and improving soil structure, organic mulches improve the water penetration to the soil and reduce soil runoff compared to bare soil.

    In contrast to organic mulches, plastic mulch films are impermeable to liquid water. Thus, they do not allow rainfall water penetration into the soil covered by the film. Rainwater that reaches the plastic film flows to the soil area between the beds and may result in soil runoff and soil erosion.

    In conclusion, both organic mulches and plastic mulch films are useful tools that help growers conserve soil moisture and increase irrigation efficiency.

  • Plethora of Plant Diseases Following Rainy Season for Alabama Producers

    University of Georgia photo shows effect of downy mildew disease.

    A wet 2020 has had Alabama vegetable and specialty crop producers fending off plant diseases. Even before the state encountered a couple of hurricanes, including Sally in mid-September and Zeta in late October, it had already received its share of rainfall. 

    Not surprisingly, the excess moisture led to numerous plant diseases, according to Ed Sikora, professor and Extension plant pathologist in the Department of Entomology and Plant Pathology at Auburn University.

    Sikora Comments

    “We saw quite a bit of gummy stem blight on watermelons. We also saw downy (mildew) and anthracnose on things like cucumbers as well as pumpkins,” Sikora said.

    “I think most of the established growers realize that when it’s wet conditions like we had this summer, that they’re going to see more disease problems. Or they see the disease problems and realize it’s so wet, and sometimes they can’t get out to spray. Sometimes it’s too wet to spray after a storm and they can’t into the fields.”

    It can be challenging for farmers to get back in the field to apply much-needed fungicides to manage any potential plant diseases following a storm.

    Be Prepared

    Sikora encourages producers to monitor upcoming weather conditions and apply fungicide sprays. Do this before a storm hits or before conditions become favorable for disease development.

    “Don’t wait until the third of the canopy is gone due to disease before you start spraying because it’s usually a lost cause by then. Growers need to anticipate the weather conditions and what diseases they’ve historically had in their fields,” Sikora said.

    “Newer growers, though, are sideswiped by these diseases because they just haven’t seen them. They get a year like this year where they’ve had adequate moisture and they’re happy. Suddenly some of these plant diseases take off on them. They don’t know what it is before they even think about spraying for them.”

  • Storing Pecans May Not Be Best Option for Growers

    Photo by Clint Thompson/Shows pecans being cleaned after harvest.

    A popular option that Georgia pecan producers are utilizing to combat low prices is to put them in storage in hopes of improved prices in the future.

    However, University of Georgia Cooperative Extension pecan specialist Lenny Wells cautions growers who take this approach.

    “That’s most of what I hear taking place. I haven’t heard a lot (of pecans) over the last (couple of weeks) being sold at the offers they were getting. There was a little here and there but not much. The issue that I see with that is I see no sign of things getting better, even holding it,” Wells said. “If they hold it there’s a risk of having this problem continue on into next year when we’re likely to have as much as we have now.”

    Decreased Prices

    South Georgia farmer Randy Hudson said prices are anywhere from 30% to 50% less than what they’ve seen the last three years. Prices are the lowest they’ve been in the last 20 years, while expenses remain high.

    The depressed market also comes amid a bumper crop across the Southeast. Instead of giving in to low prices, buyers are taking the wait-and-see approach.

    “Putting them into cold storage and holding them has always been the thing growers will do when prices have bottomed out like this, but back when that worked, we didn’t have to worry about Mexico’s production. We didn’t have to worry about South Africa’s crop coming off in May and June,” Wells said. “There’s a very narrow window there that you’re just hoping that the demand for pecans goes up during that time.

    “I don’t know when to expect the price to get any better.”

  • NIHC Receives USDA Market Access Program Funding for International Research and Promotion of Hemp

    NIHC Becomes First Hemp Organization Officially Recognized by USDA Foreign Agricultural Service as Market Access Program (MAP) Partner

    File photo shows hemp field.

    WASHINGTON – The National Industrial Hemp Council announced it received $200,000 in U.S. Department of Agricultural (USDA) Market Access Program (MAP) funding to support export market development of industrial hemp.  

    “We are grateful for USDA confidence and the recognition of NIHC as the industry leader in industrial hemp trade and marketing,” said Kevin Latner, NIHC’s Senior Vice President for Trade and Marketing who will be responsible for implementing the program.  “Today’s announcement makes NIHC a trusted partner to USDA for hemp fiber, feed, food and CBD companies looking to break down trade barriers in markets overseas.”

    MAP funds are administered through USDA’s Foreign Agricultural Service (FAS). Through the MAP program, FAS partners with U.S. agricultural trade associations, cooperatives, state regional trade groups and small businesses to share the costs of overseas marketing and promotional activities that help build commercial export markets for U.S. agricultural products and commodities. These funds can be used for facilitating trade missions and meeting with industry stakeholders and government regulators overseas. 

    NIHC programs will focus on Europe and China and include market research, trade policy and trade facilitation. The global industrial hemp and products market was estimated at $11.1 billion in retail sales in 2019.  With an annual growth rate of 52%, driven by continued strength in textiles, food and industrial uses and hemp-derived cannabidiol (CBD), the global market is forecast to be worth $89 billion by 2025.   

    Hemp for industrial use, textile and CBD market is expected to quickly expand and be the primary driver of global industry growth. By 2021, the global trade of hemp is forecast $8.1 billion across all markets, representing a three-year compound annual growth rate (CAGR) of 83%. Europe, China, and Canada are currently the primary sources of industrial hemp. With the passage of the 2018 Farm Bill, the U.S. has become the world’s third largest producer of industrial hemp.  

    Europe has rapidly developed a robust hemp and CBD market.  Europe is also a strong producer of industrial use hemp products with $424 million in industrial product sales. China has led global markets in textiles with almost 80% of the $1.7 billion hemp textile market in 2019.   

    In addition, National Industrial Hemp Council members will now have unprecedented access to United States trade negotiators; foreign government counterparts; and a network of international hemp industry association counterparts. Foreign governments understand that NIHC is now supported by the U.S. government and represents U.S. industry interests. 

    Market Access Program funds can be used by NIHC throughout the world to support market access and trade policy work, international trade promotion including supporting business-to-business facilitation and consumer and brand marketing.

    MAP funds for 2021 will be administered to NIHC through the Food Export Association of the Midwest USA.   

    “We’re extremely confident and trust that NIHC will represent the best interests of U.S. industrial hemp abroad. We’re excited to be working with them as part of the USDA cooperator community,” said Tim Hamilton, Executive Director of Food Export Association of the Midwest USA.

    About the National Industrial Hemp Council: The National Industrial Hemp Council provides high-quality networking and resources for its members, from farm to consumer. Its leadership is composed of leading international, federal, state, private industry, and government professionals throughout the sector. The organization is dedicated to furthering market development, assisting members in entering the industry, and educating consumers on industrial hemp and its applications. For more information please go to www.hempindustrial.com.

  • USDA Restricts PACA Violators in California, Florida and Texas

    November 13, 2020 – General News

    PRESS RELEASE: WASHINGTON, Nov. 13, 2020 – The U.S. Department of Agriculture (USDA) has imposed sanctions on three produce businesses for failing to meet contractual obligations to the sellers of produce they purchased and failing to pay reparation awards issued under the Perishable Agricultural Commodities Act (PACA).

    These sanctions include suspending the businesses’ PACA licenses and barring the principal operators of the businesses from engaging in PACA-licensed business or other activities without approval from USDA.

    The following businesses and individuals are currently restricted from operating in the produce industry:

    JRP Group, d/b/a Prime Produce BB #:365482, operating out of Los Angeles, Calif., for failing to pay an $11,984 award in favor of a California seller. As of the issuance date of the reparation order, Kay Persaud, Joshua C. Roach and Rajendra S. Persaud were listed as the officers, directors and/or major stockholders of the business.

    Natura Fresh LLC BB #:348926, operating out of Miami, Fla., for failing to pay an $3,168 award in favor of a Florida seller. As of the issuance date of the reparation order, Julia Espinal was listed as a member of the business.

    Talygap Produce Inc. BB #:328936, operating out of McAllen, Texas, for failing to pay a $3,510 award in favor of a Texas seller. As of the issuance date of the reparation order, Gustavo Adolfo Ponce Reyes was listed as the officer, director and major stockholder of the business.

    PACA provides an administrative forum to handle disputes involving produce transactions; this may result in USDA’s issuance of a reparation order that requires damages to be paid by those not meeting their contractual obligations in buying and selling fresh and frozen fruits and vegetables. USDA is required to suspend the license or impose sanctions on an unlicensed business that fails to pay PACA reparations awarded against it as well as impose restrictions against those principals determined to be responsibly connected to the business when the order is issued. Those individuals, including sole proprietors, partners, members, managers, officers, directors or major stockholders, may not be employed by or affiliated with any PACA licensee without USDA approval.

    By issuing these penalties, USDA continues to enforce the prompt and full payment for produce while protecting the rights of sellers and buyers in the marketplace.

    For more information, contact John Koller, Chief, Dispute Resolution Branch, at (202) 720-2890, by fax at (202) 690-2815, or PACAdispute@usda.gov.

  • UGA Researcher Part of Grant Studying Efficacy of Essential Oils in Organic Fruit Production

    File photo shows blueberries.

    Organic agricultural production is increasing in Georgia. Jonathan Oliver, University of Georgia (UGA) assistant professor and small fruits pathologist, wants to help producers be more efficient by researching ways to protect organic blueberries from diseases.

    According to UGA Extension, the U.S. Department of Agriculture National Institute of Food and Agriculture awarded a $2 million grant to the team of 15 scientists from 5 universities and the USDA Agricultural Research Study, including Oliver at UGA. While the group of researchers will focus on various fruits, including peaches, mangos and avocados, Oliver’s focus will be centered on blueberry production, the highest value fruit crop in Georgia. All will be seeing if essential oils can help suppress certain pathogens and pests.

    Oliver Comments

    Oliver

    “The essential oils organic grant is actually looking at a lot of different crops in the southeast and whether essential oils could have a role in a disease management program. There is data showing that essential oils can have antifungal properties and things like that if used in the laboratory or the greenhouse. But field studies are lacking,” Oliver said. “Since Georgia is one of the top producers of blueberries in the country and definitely in the Southeast, my role on this grant as the blueberry pathologist at UGA is to look at whether these products can be effective in the field and help our organic growers here that are growing blueberries.”

    Oliver will apply the essential oils in the field in a similar manner that producers apply other products. He’ll also be looking at diseases that affect blueberries after harvest. Will this treatment have a post-harvest impact if applied prior to harvest?

    “Cultural practices are really important in both conventional and organic, but in organic, they’re especially important. As far as chemical management in organic systems, you’re really limited on the types of products you can apply. No synthetic pesticides can be used. Typically, the synthetic pesticides are the ones that are going to be most effective. Usually, organic pesticides need to be applied more frequently to obtain control, if you can obtain control,” Oliver said. “We really need a lot more tools for our organic growers to help them manage diseases.”

    Grant Background

    The four-year project will support researchers who specialize in fruit crop management and physiology, plant pathology, entomology, post-harvest biology and organic production.

    In the research, scientists will:

    • Begin to test plant disease efficacy claims of essential oil products marketed for organic producers.
    • Evaluate organically certified plant essential oils on targeted pathogens such algal stem blotch, brown rot, scabs, gray mold and powdery mildew.
    • Determine the efficiency of essential oils on fruit shelf life through postharvest testing.
    • While arthropod pests are not the primary focus of this research, researchers also will test the efficacy of essential oils against insects including scales, thrips and mites.

    Organic food sales topped $50 billion in the United States in 2018. According to the Organic Trade Association, fruits, vegetables and specialty crops comprised of 36.3% of the total organic sales, which is up 5.6% from the previous year.

  • Hurricane Eta Soaks Already Saturated South Florida

    Graphic from National Weather Service/Shows Eta’s path for the next couple of days.

    An already saturated South Florida was inundated with rainfall from Hurricane Eta this week. The result were fruit that were either lost or will suffer from expected disease pressure, according to Gene McAvoy, University of Florida Regional Vegetable Extension Agent IV Emeritus.

    “We did have quite a lot of rain. We didn’t really need it. I’m sure we’ll see more disease as a result,” McAvoy said. “Some of the guys that had beans and corn direct seeded stuff, they’re going to experience some stand loss, some damping off. Sugarcane planting was delayed.

    “I’m sure we’ll see some increased calls in terms of cracked fruit in tomatoes and some scarring from wind scarring; disease. There’s a lot of bacteria around. I don’t know how much of that will show up on the fruit, it’s too early to tell yet.”

    Plant Disease

    Plant disease is not uncommon following excessive rainfall. It could really be an issue, though for plants in fields that have been completely saturated and having trouble drying out.

    “I’m sure we’re going to see things like melons; I’m hearing more gummy stem blight and gummy stem loves water; more phytophthora, bacteria. I’ve been out in some pepper fields; specialty peppers, non-resistant varieties, there’s a lot of leaf drop and defoliation going on,” McAvoy said.

    Weather Challenge

    Weather remains a year-round challenge for Florida vegetable growers. The region has experienced two months of excessive rainfall, following a relatively dry summer. McAvoy estimated that in the Fort Lauderdale area, it had received 26 inches over the past month. It’s twice as much as what his area has seen, and they’ve seen quite a bit.

    “We actually had a relatively dry summer. Until about the first week of September it was pretty dry. Then it really got wet,” said McAvoy, who is located in between Immokalee and LaBelle. “My personal property has been basically under water. I have a pasture, but it’s ankle deep across 39 or 40 acres.”

  • Alabama Pecan Producer Still Picking up Pieces Following Hurricane Sally

    Picture from Adam Bertolla/Shows massive pecan tree uprooted by Hurricane Sally.

    Hurricanes wreaked havoc on agricultural production this summer and fall. Unfortunately, pecan producers were not immune to nature’s fury.

    Just ask Alabama farmer Adam Bertolla. He lost ¾ of this year’s crop as a result of Hurricane Sally in mid-September. He also lost 250 trees or a third of his pecan operation.

    “It killed me, because I lost over a third of my trees and these trees are over 90-year-old trees. People say, ‘You going to replant.’ I say, ‘Hell no, I’m not going to replant,’” said Bertolla, referring to Hurricane Sally that made landfall in Alabama on Sept. 16. “No. 1, there’s going to be some more storms come; No. 2, I’m too old, even though I’m in my early 50s. There’s just not any use in doing it. That’s what hurt me the worst is losing my trees.”

    What’s Left for This Year?

    “You talk about a 90-year-old tree, he’s a man now. Then you’ve got all of that stuff to clean up. We cleaned up the orchard without running over no more than we could. It looks like a guestimate of what I saved was probably a little less than a fourth. We probably lost three-fourths of my crop due to that much rain. In one orchard, they floated off and went down the river. They’ll float.”

    Bertolla estimates that he lost 250 trees. It can’t be understated how massive a loss it is considering the age of these trees and the yields they can potentially produce every year.

    “That’s a third of what I’m never going to have again. The other trees can’t make up for it,” Bertolla said. “My grandpa was a pretty young man when he planted those trees. It just makes you sick when see all of that. We’ve had storms and we’ve lost 50 and 100 here and yonder through the years but the (orchard) is really open now. There’s a lot of big gaps out there.”

    Eye of the Storm

    Bertolla’s pecan trees are located about 30 miles north of Gulf Shores, Alabama, which was in Sally’s direct path when she finally made landfall as a Category 2 Hurricane. The slow-moving storm that featured winds over 100 mph and torrential flooding overpowered massive pecan trees. It was a sight to see and left destruction that Bertolla was still picking up the pieces from this week.

    “If you’ve never seen a big pecan tree uprooted it’s something to see how big the roots are and how it was trying to do everything it could to hold onto the dirt but it just couldn’t. It was just too saturated that it couldn’t hold on any longer,” he added.

  • Florida Urban Tree Canopy Gives Oxygen, Shade – Saves $4 Billion a Year

    UF/IFAS photo/Urban forestry in Tampa Bay, Florida.

    November 12, 2020

    By: Brad Buck, 352-875-2641 (cell); bradbuck@ufl.edu

    Trees give us shade to cool off and oxygen to breathe – and they provide Florida cities with $4 billion in benefits a year, collectively, UF/IFAS researchers say.

    These include savings in air pollution removal, stormwater runoff and carbon sequestration and storage, said Andrew Koeser, UF/IFAS associate professor of environmental horticulture.

    To reach their findings, UF/IFAS researchers surveyed tree canopies in Florida’s metropolitan and micropolitan areas, defined as distinct economic regions having one or more core cities. Florida has 29 such regions, spread out over 51 of its 67 counties. Scientists define tree canopy cover as the percent of a land area covered by leaves and branches when viewed from above.

    “Florida is known for its natural resources and beauty, and its urban forests are the most direct connection to nature most of the state’s residents have,” Koeser said. “As such, this work is an important first step in monitoring and valuing some of the many things trees do to enhance our lives.”

    Koeser and several UF/IFAS colleagues put their assessment into a new UF/IFAS Extension document, in which they outline the many ways urban canopy gives back quantifiable benefits.

    To calculate these benefits, UF/IFAS researchers used software known as the iTree Canopy Model from the U.S. Forest Service. The iTree is a common model that governments worldwide use to put a value on their urban trees, said Koeser, a faculty member at the UF/IFAS Gulf Coast Research and Education Center in Balm (Hillsborough County), Florida.

    This report is part of a statewide urban canopy assessment funded by the Florida Forest Service and the UF/IFAS Center for Land Use Efficiency (CLUE), and this is the first time anyone has applied the iTree model to get a statewide assessment of the benefits of urban trees.

    In the past, UF/IFAS faculty have written similar documents for individual cities like Tampa, Orlando, Fort Lauderdale and one for Miami-Dade County.

    “These numbers are broad estimates meant to give folks an idea of the magnitude of the benefits,” Koeser said. “It is an attempt to quantify urban green infrastructure in a way that is comparable to roads, fire truck fleets and other things that cost money and produce benefits.”

  • Remember to Plant Fruit Trees During Dormancy

    developing
    File photo shows peach tree in bloom.

    Soon it will be time for homeowners and commercial growers to plant their fruit trees in Alabama.

    Edgar Vinson, assistant research professor and Extension specialist in the Department of Horticulture at Auburn University, reminds producers, whether they’re planting peach trees or apple trees, the time to do so is during the late fall or winter when the plants are dormant.

    “You can plant an actively growing tree but it really puts a lot of stress on it. The idea is you want to keep as much moisture in the plant. If you’ve got a plant that’s got leaves, it’s transpiring and losing water. The roots aren’t really developed to the point that it’s extracting enough water and nutrients to keep up with the water that’s being lost,” Vinson said.

    Soil Factor

    Vinson

    One of the most important factors to consider, whether you’re planting peach trees, apple trees, blueberries or figs, is the soil. Soil testing is crucial and needs to be done well in advance.

    “You definitely want to be mindful of your soil. Soil tests are really important. You want to know how much nutrients are in the soil,” Vinson said. “If there’s any deficiencies, you want to be able to correct those especially with a perennial crop like fruit tree crops.

    “It’s very difficult to course correct once you get those in the ground. Having a soil test is important. If there’s anything that has to be changed, like if the pH is off, it’s really good to know so you can apply lime.”