The most dangerous threat to the peach industry in the Southeast is Oak Root Rot, a soil-borne fungus that can wipe out peach trees, according to Edgar Vinson, Alabama Extension Professor of Horticulture.
Oak Root Rot or Armillaria Root Rot, causes stunted leaves, yellow defoliation, chlorotic leaves, death of branches and, ultimately, death of the tree.
Unfortunately for peach producers, there’s not many management options available to offset the death sentence for peach trees that are planted in a field with this disease.
“As far as we know, once it’s in the soil it’s there probably for good,” Vinson said. “Once the tree starts to succumb to it, there’s no remedy for it. There’s some things to delay it, if you have a tree that’s planted in the soil that has Oak Root Rot. If you’re planting into soil that has Oak Root Rot, there’s really no remedy for it. It will eventually take over the tree and take the tree out.”
One Option
Farmers can implement a root collar excavation. This is a management tactic that producers utilize to remove soil from the crown of the tree to prevent the fungus from growing on the crown. This only delays the inevitable. Eventually the tree will succumb to the disease, but this practice extends the life of the tree so the grower can get more harvests out of it.
The best option would be to plant a resistant root stock. However, one is not broadly available yet.
“Most peaches don’t come from the nursery on their own roots. They’re budded onto a rootstock that’s tolerant to a particular soil condition or diseases. You have a desirable peach variety that’s grafted onto a resistant rootstock. That’s typically how we receive our peaches, apples and a number of other crops,” Vinson said.
Oak Root Rot symptoms usually appear between 5 to 7 years after planting.
“It’s a disease that’s recognized all over the Southeast. We’re currently working on ways to mitigate the damage,” Vinson said.
There is currently little to no science-based information on the efficacy and safety of most essential oils in pest management of fruit crops like blueberries, so a multistate team is working together to learn more.
By Josh Paine for UGA CAES News
Organic fruit and vegetable growers want to meet the recent uptick in national consumer demand, but they need additional tools to battle pests and diseases that often accompany organic crop growth.
One such tool may be the use of essential oils. That’s why the U.S. Department of Agriculture National Institute of Food and Agriculture awarded a nearly $2 million grant to a team of scientists for an Organic Agriculture Research and Extension Initiative project to study the degree to which essential oils can help suppress certain pathogens and pests.
Jonathan Oliver, assistant professor in the University of Georgia College of Agricultural and Environmental Sciences at the UGA Tifton campus, is part of the team of 15 scientists who will work on this project nationwide. Researchers from the University of Florida, Clemson University, the University of California, Riverside, the University of Hawai’i at Manoa and the USDA Agricultural Research Service will collaborate on the project.
In his role as a small fruit pathologist in the Department of Plant Pathology, Oliver will investigate the use of essential oils in organic blueberry production, the state’s top fruit crop.
“Blueberries are the highest value fruit crop in Georgia, and organic blueberry production represents a growing proportion of our total acreage,” said Oliver. “Nonetheless, organic production of blueberries in Georgia faces many challenges, because our hot, humid climate is ideal for many disease issues including fruit rots and leaf spots. Our growers need better tools to help them manage these disease problems.”
Funding for the four-year research program will support scientists with expertise in fruit crop management and physiology, plant pathology, entomology, postharvest biology and organic production.
To carry out the project, scientists will:
Evaluate the plant safety and horticultural impact of essential oils in managing diseases in fruits including blueberries, peaches, mangos and avocados.
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 as algal stem blotch, brown rot, scabs, gray mold and powdery mildew.
Determine the efficiency of essential oils on fruit shelf life through postharvest testing.
Test the efficacy of essential oils against insects including scales, thrips and mites, although arthropod pests are not the primary focus of this research.
After they gather their new data, participating scientists will communicate the results of their research to organic fruit farmers and those who grow conventional crops, so that those producers can rapidly adopt any new practices. Scientists will also evaluate the effectiveness of the project through continuous feedback from stakeholders.
“Through this research project, we hope to provide Georgia growers with the information they need to make decisions regarding the use of essential oils as a part of their organic fruit disease management program,” said Oliver. “Since Georgia is the largest producer of blueberries in the Southeastern U.S. and one of the top producers in the nation, providing Georgia growers with information and tools for safe and effective organic disease management has the potential to have a broad impact in Georgia and on the Southeastern organic blueberry production industry as a whole.”
Organic food sales topped $50 billion in the U.S. in 2018. Statistics from the Organic Trade Association tell part of the story of this growing market: fruits, vegetables and other specialty crops combined to make up 36.3% of total organic sales, up 5.6% from the previous year.
The pecan crop in the Southeast remains ahead of its normal production schedule, though cooler temperatures in recent weeks have slowed the crop’s progress, says Andrew Sawyer, University of Georgia Cooperative Extension area pecan agent for Southeast District.
“I think the cool (weather) has actually slowed us down a little bit,” Sawyer said. “The crop was already 10 (days) to two weeks ahead anyway. We’ll still be ahead in the long run.”
Farmers have already begun harvesting pawnee varieties. In normal production years, pawnees are usually the first varieties harvested, and then there is a gap before the rest of varieties are mature enough for harvest. However, others are already showing signs of being ready to be picked, Sawyer said.
“Desirables are cracking pretty strong which is probably on the early side for them, too. They’re looking good. Everything’s about to really get ramping up,” Sawyer said.
All in all, this year’s pecan crop is projected to be one of the largest crops in recent memory, especially since Hurricane Michael impacted the region in 2018, disrupting production.
“Definitely the biggest in a long time. It is going to be a big crop,” Sawyer said. “Expect some lower prices for sure.”
Fire ant control is essential for Alabama vegetable growers hoping to protect their crop this fall. Alabama Cooperative Extension warns producers that fire ants are known to be pests of numerous vegetable crops, including okra and potatoes.
Ayanava Majumdar, Alabama Extension Professor, said fire ants can especially be harmful to vegetables because they’ll congregate on plants that have a heavy load of aphids. They will tend to protect aphids and other honeydew producers on vegetables. Fire ants can also damage the crops themselves and contaminate the produce.
“I think the issue is they get on plants that get a heavy load of aphids. They follow aphids. If plants have aphids you often have the ants protecting the aphids,” Majumdar said.
Few Management Options
Alabama Cooperative Extension offers producers a few management options. Control fire ant mounds around or outside the vegetable production area to prevent them from moving into the garden or field. Also, manage excessive plant residue on the soil. This will help increase detection of foraging ants, provides ants fewer places to hide and make it easier to scatter bait insecticides on open ground.
The best time to apply broadcast baits is now through Oct. 15. Mound treatments may be done year-round on warm, sunny days above 65 degrees F when the fire ants are active. Majumdar attests that the ants are active now.
“They’re pretty active in my peanut fields. They’re pretty active in and around my vegetable fields and my garden. They’re very active,” Majumdar said.
“We are so excited to announce Bay and Lake Pharmacy as our first pharmacy partner,” stated Jammie Treadwell, co-owner of Treadwell Farms. “They truly care about the community and the people who live here. By carrying our Treadwell Farms hemp CBD extract product line, they will make a lasting impact on those who are looking for a more natural option for their body’s wellbeing.”
Treadwell Farms officially launched the first of its CBD product line in May 2020, in tandem with the announcement of receiving one of the first hemp cultivation licenses in Florida. After receiving its food permit in February 2020, the company was able to process the first of its high potency, artisanal CBD line – 1200mg bottles of Essential Blend Hemp CBD Extract Oil and Citrus Spice Hemp CBD Extract Oil. Both are infused with organic MCT oil and Sunflower Lecithin. The Citrus Spice Extract also contains organic Orange, Cinnamon, Turmeric and Ginger.
“We are excited to be working with a locally-owned CBD company who’s embodies high quality and production of its products,” said Gordon Punt, registered pharmacist for Bay Pharmacy. “Treadwell Farms high potency CBD, combined with essential oils, provide a unique product to offer our patients. Supporting local businesses is important to us, especially supporting our local farmers. We’re looking forward to a successful future – together – with Treadwell Farms.”
All the Treadwell Farms CBD Hemp Extract tincture droppers come with .25mL, .50mL, .75mL, and 1mL measurements to help manage dosage intake. “We approach our products with purposeful intent – especially for the clients of our trusted partners like Bay and Lake Pharmacy,” said Jammie Treadwell, co-owner of Treadwell Farms. “Each bottle contains 1200mg of CBD, and that’s a beautiful thing because it means you’re receiving high potency, high-quality CBD oil every time. It’s also by design because it makes dosing easy – 10mg per quarter dropper.”
All Treadwell Farms products are produced in the company’s processing facility in Umatilla, Fla. The company’s ultimate plan is to be a cultivator of the hemp industry for the region by advising local farmers through the planting, harvesting, and processing of the plants, and then ultimately extracting the cannabinoids (CANNA-BIN-OIDS), including CBD, from Florida-grown hemp plants for packaging and sale.
For more information about Treadwell Farms, visit www.TreadwellFarms.com. Follow the Treadwell Farms blog, which provides insightful information about CBD and the hemp plant – amongst other details throughout the year. Follow on Facebook and Instagram at Treadwell Farms.
The nation’s essential agricultural industry has worked relentlessly through the COVID-19 pandemic to ensure food is put on the tables of American families. Agricultural employers recognize that the health and safety of their employees are imperative to the success of their operations. These employers also recognize consumer demand for fresh, safe and nutritious produce. For years, agricultural employers have adhered to strict policies assuring the health, hygiene and safety of their employees. Now, these employers have implemented even more protocols in response to the COVID-19 pandemic.
During the 46th annual Agricultural Labor Relations Forum presented by the Florida Specialty Crop Foundation, Michael Marsh, president and CEO of the National Council of Agricultural Employers (NCAE), spoke about essential protections for agricultural workers during the COVID-19 pandemic.
Marsh says growers have been doing a great job following the Centers for Disease Control (CDC) guidelines for agricultural workers by promoting safety on and off the farm.
Across the agriculture sector, employers have instituted best practices including social distancing, enhanced hygiene and sanitation stations and procedures, special COVID-19 employee training, the use of personal protective equipment (PPE) and limitation of non-essential visits and travel.
In addition to following CDC guidelines, industry members are also calling for the federal government to take additional steps and devote new resources to help growers protect their employees.
Alternative housing structures to facilitate greater social distancing, accessible and timely COVID-19 testing resources, and prioritizing PPE and future vaccine distribution for the food and fiber supply chain are among the list of items that the agriculture industry would like to see addressed.
Since hotels aren’t always available in rural communities, housing with more rooms and more beds would allow for additional social distancing among employers.
The NCAE published a frequently asked questions document for H-2A employers regarding COVID-19 issues. See the document.
Ashley Robinson, AgNet Media communications intern, wrote this article.
According to the UGA Extension blog, Pam Knox, University of Georgia Cooperative Extension Agricultural Climatologist, said the impacts for the Southeast from soon-to-be Hurricane Delta remain the same, with the biggest effects in Alabama, western Georgia and western end of the Florida Panhandle.
A stronger storm means that storm surge along the coast is likely to be higher than it would be if the storm were weaker. By the time it makes landfall Friday night, it should be moving pretty good, which will reduce the amount of rainfall at any one location. You can get updated information from the National Hurricane Center.
Delta developed six weeks earlier than the only other time we have had a storm Delta back in 2005, another very active year.
The greatest risk of whiteflies to fall vegetable production are the viruses they can transmit, according to Meade McDonald, Syngenta Insecticide Product Lead. That’s why growers need to utilize every weapon in the arsenal this year to combat a threat that is reaching its highest infestations since 2017.
“Using multiple modes of action and using as many tools that are available to the grower in his toolbox is really important to prevent tolerance and resistance from manifesting to these pests,” McDonald said.
Virus Vectors
Whiteflies can transmit the cucurbit leaf crumple virus and cucurbit yellow stunting disorder virus. According to University of Georgia crop loss estimates for fall 2017, these viruses caused between 30% and 50% of crop loss in squash and cucumbers and nearly 80% of crop loss in snap beans.
“This is a difficult to manage pest. Growers need as many tools as possible to control this pest. Controlling whiteflies is what I would call, it requires a programmed approach. There’s no one single crop protection product that a grower can use and deploy and have successful whitefly control. It’s going to take multiple modes of actions, multiple sprays,” McDonald said.
“I think growers in the Southeast are using a soil-applied insecticide; whether it be a neonic or a diamide, it is a great way to start the season strong and keep populations low. That has to be followed by timely in-season foliar applications of products like IGRs or a foliar diamide. Minecto Pro is one of our new products. It’s a great alternative to soil applied neonics.”
McDonald said a soil application is best followed by multiple foliar applications on 7 to 10-day intervals. That is what it is going to take to keep populations low and prevent viral transmission.
Environment Conducive to Whiteflies
Southeast growers can produce a spring and fall crop thanks to an environment that’s conducive to growing crops year-round. However, that makes certain cucurbits like squash especially vulnerable to whitefly pressure.
When temperatures don’t get cold enough to kill off the wild hosts, as was the case this past winter; then whitefly infestations are primed to be high and out of control earlier than normal.
“When you think about fall vegetable production in the Southeastern United States, when growers go in and plant fall vegetable crops, they’ve really got to be concerned about whiteflies. They’ve got to be ready to anticipate and be proactive,” McDonald said.
“The environment, simply in the Southeastern United States for the pest to manifest and for populations to build is just simply ideal. You’ve got ideal host crops almost year-round for whitefly populations not only to survive but thrive. We know these late summer, early fall temperatures enable that life cycle to speed up and populations can really be explosive this time of year, especially.”
Clemson Extension agents provided updates in The South Carolina Grower this week about the status of various crops being produced throughout the state.
Weekly Field Update 10-5-20
Coastal
Zack Snipes reports, “The cooler weather and lots of rain have brought out the diseases. I saw some watermelon diseases last week including gummy stem blight. We need to protect our foliage just a few more weeks to finish off those melons so keep at the spray programs if you can. Whiteflies continue to hammer us in all crops this fall. Strawberry planting is just about upon us. Rains and wet ground have slowed some farms from laying plastic. Remember that pre-plant fertility and herbicides are critical to spring success. Spartan and Devrinol are the only two pre-plant herbicide options this late in the season. Other products require a 30-day wait period. Let me know if you want me to come check your strawberry plugs before you plant them.”
Gummy stem blight on watermelon foliage. Photo from Zack Snipes.
Rob Last reports, “Fall crops are looking good in this area with good development in brassicas and beets. Insect and disease activity remain moderate, however, with cooler weathers and rainfall, scouting will be critical to success for these crops. Adult moths are very active at present, so be on the lookout for eggs and caterpillars. Plastic is down and awaiting strawberry planting in the next week.”
Growers are ready for strawberry planting. Photo from Rob Last.
Midlands
Justin Ballew reports, “The weather has been pretty fall-like and enjoyable over the last week. The cooler temperatures and high amounts of recent moisture have diseases like powdery mildew, downy mildew and anthracnose increasing. Caterpillar activity has increased in the last week as well. Be sure to rotate modes of action when spraying for caterpillars. Strawberry growers are ready to plant and will probably start within the next week.”
Powdery mildew has been picking up on fall cucurbit crops. Photo from Justin Ballew.
Sarah Scott reports, “Daytime temperatures have been mild with cooler night temps. Early last week, areas saw anywhere from trace amounts to 2 inches of rain. Low spots in fields may remain wet and this could lead to potential problems. Peppers are looking good as well as eggplant and late squash. Brassica crops are having some issues with aphids causing leaf curling. Pecans are beginning to fall as well. Scab seems to be particularly bad this year, most likely because of wet weather during critical spray times for fungal management in late June and July.
Pecan scab has been rough this season. Photo from Sarah Scott.
Pee Dee
Tony Melton reports, “Greens are growing fast with cool temperatures; however, beans, peas, pickles and sweet potatoes have slowed down with these temperatures. Most sweet potatoes need to find a home. We are using a lot of potassium phosphide to keep down root rot especially on greens. Most growers also use it as a dip for strawberries transplants or put through drip system as soon as they plant. Getting ready to plant strawberries as soon as the transplants get here.”
Upstate
Kerrie Roach reports, “Clear skies since Tuesday with cool fall temperatures at night and warm days has consumers looking for all things fall. Growers with pumpkins, gourds, mums, corns stalks, and/or anything fall-related have been busy keeping up with demand. Agritourism demand/opportunities have picked up significantly in the last few weeks. Apples are in peak season with Stayman being one of the current varieties available.”
Andy Rollins reports, “Upstate peaches are finished up for the year, but muscadines are still being harvested, although slowing some and strawberry planting is in full swing. I was called to examine poorly growing peach trees at an upstate farm. The majority of trees were dying from the most devastating disease of peach ‘Oak Root Rot.’ There was gumming at the base and I was fully expecting a greater peach tree borer problem but closer examination and cutting of the below ground bark revealed the Oak Root Rot fungus growing at the base of the trees. When pushing your older peach trees up be sure to examine the main roots for the sign of this disease which is the white to yellowish fungal growth deep inside of the bark below the soil level. There are a few other fungi that can have a similar symptom but they tend to grow just on dead tissue and don’t grow as deep into the wood of the tree. There are some things you can do about it, but proper identification comes first.”
Gumming and yellowish white fungal growth at the base of a peach tree from oak root rot. Photo from Andy Rollins.Poor tree growth as the result of oak root rot. Photo from Andy Rollins.
The Georgia Department of Agriculture Produce Safety Team is offering a virtual two-day Produce Safety Alliance Grower Training via Zoom on Oct. 21 and Oct. 22 from 8 a.m.-noon.
Any produce grower who grows, packs, harvests and/or holds covered produce, makes more than $25,000 in annual produce sales (on average, based on the past three years of sales), and does not qualify for a Produce Safety Rule exemption is required to attend this training under new federal regulations.
This PSA Grower Training course satisfies the FSMA Produce Safety Rule requirement outlined in §112.22(c), which requires ‘At least one supervisor or responsible party for your farm must have successfully completed food safety training at least equivalent to that received under standardized curriculum recognized as adequate by the Food and Drug Administration.’
