According to the Southeastern U.S. 2021 Vegetable Crop Handbook, crop rotation is key in preventing the buildup of soil-borne pathogens. Specialists from universities across the Southeast implore producers to consider an effective rotation sequence that consists of crops from different families that are poor or non-hosts of these pathogens.
The longer the rotation the better the results will be. A 3-to-5-year rotation is recommended.
However, growers must weigh the practicality of rotating their crops on the availability of land, the markets, what alternate crops that are able to grow in the area, the pathogens and the purpose of the rotation.
Clemson Extension agents provide updates in the The South Carolina Grower this week about the status of various crops being produced throughout the state.
Weekly Field Update
Statewide
Dr. Matt Cutulle reports, “Burndown herbicide efficacy can be reduced in colder weather, especially systemic products such as glyphosate (Reduced translocation in the cold means herbicide does not move through the plant as much). A contact herbicide like Gamoxone is not significantly impacted by cold weather, thus it might be a good option to use on medium to small weeds. If you have to use glyphosate make sure that the formulation is loaded with a non-ionic surfactant (NIS) and then add 2.5% Ammonium Sulfate (AMS). If the glyphosate formulation is not loaded with NIS, added an NIS product (should contain at last 90% active ingredient) such as Induce at 0.25% (quarter of 1%) in the tank mix.”
Coastal
Zack Snipes reports, “Now is the perfect time to gear up for the upcoming season with preventative maintenance on sprayers and tractors. Proper spray coverage is absolutely essential when spraying expensive pesticides and nutrients. Why would you buy a jug of pesticide for $800 and not have it properly applied? I was at a farm last week working on a spray trial and we took a few hours to clean out screens, filters, and orifices in the sprayer. The sprayer I was working on had 5 out of 10 nozzles completely clogged and corroded. We would only get half or less coverage since the nozzles were so clogged. Once we cleaned everything, we needed to recalibrate our sprayer since we were actually putting out product through all of the nozzles. Take the time and get things ready for the year.”
Proper spray coverage on a nice looking crop of strawberries. Photo from Zack Snipes.
Midlands
Justin Ballew reports, “Last week stayed pretty cool (high temps in the 50s), wet and cloudy. Crops aren’t growing very fast right now. We still have a few greens being harvested, but we’ve slowed down from the New Years rush. Most of the strawberries I’ve looked at are still around the 2-to-3 crown stage. We’re seeing some aphids here and there, but those are rarely anything to be concerned about. Instead, keep checking for mites. Spider mites are active when daytime temperatures are over 50 degrees, so even though it’s chilly to us, they’re active for most of the winter. Fields planted adjacent to tomatoes back in the fall need to be scouted especially well.”
Great stand of rye between the rows of this strawberry field. This will help tremendously with weed suppression. Photo from Justin Ballew.
Pee Dee
Bruce McLean reports, “Be sure to get out and scout your strawberries. Starting to see a fair amount of Phomopsis in the fields. Captan will give some control, but Rally is a better option. Also, starting to see some Botrytis showing up on ripening fruit… that fruit that has been able to escape frost events and develop. Removal of infected fruit and dead leaves will help reduce pathogen when it comes time to flower and fruit. Across the northern portion of the Pee Dee the strawberry crop is pretty varied in development and appearance. Some plantings are well behind others. This is primarily due to the frequent and heavy rains since planting. Any plants that may have been set (even the least bit) low, experienced loose soil to be washed down around the crown, burying the crown too deep. With the crown being buried, the plants were either stunted or killed. Stunted plants can recover, but likely will not develop and yield properly come spring. Now is the time to begin winter pruning of blueberries, blackberries and muscadines… as well as many fruit trees. Proper winter pruning will go a long way towards improving yield, plant health, overall plant architecture and size management. Ideally, winter pruning for perennial fruiting plants should be performed between early January through early March.”
Botrytis already showing up on strawberries. Photo from Bruce McLean.
Tony Melton reports, “Wet, wet, wet. Badly need to start bedding for stale-bed-culture. Putting off bedding sweet potatoes until March. I have seen a lot of spider mites on strawberries and started to spray to get them under control. However, too wet to get tractor in fields, so many farmers are using backpack mist sprayers to get job done.”
Photo submitted by Stanley Culpepper/UGA: Shows a blend of yellow and purple nutsedge.
Weed management in vegetable crops across the Southeast remains a diverse and complicated practice that all producers need to be reminded of.
“There are so many components that a vegetable grower has to consider, especially when it comes to weed control. Some production systems you can use tillage. Some you can’t. Some you have plasticulture in a fumigant system. Some that you don’t,” University of Georgia Cooperative Extension weed specialist Stanley Culpepper said.
“Then when you start thinking about herbicides, we’ve been very fortunate over the last 10 years, getting our growers a lot of cool herbicide tools as a component to their management program, but when you’re a vegetable producer and going to have a crop and be in and out in 60, 80, 90 days, you’ve got to think about herbicide carry-over. I can or I can’t use herbicide ‘A’ because of what it could potentially do to the next crop, which means you’ve got to know what the next crop is going to be. You know vegetable guys as good as I do, a lot of times, they just don’t know.”
Producers have to implement the right herbicide and do so at the right rate. They have to use the right irrigation program. The tank also has to be perfectly clean.
“The complexity goes on and on for a vegetable farmer. A lot of decisions have to be made in a 12-month cycle because we could be producing three crops in a lot of our farms,” Culpepper said.
Weed Problems
Certain weed species are also problematic at different times of the year. Weeds that are normally a concern for producers in the spring are not the same as those that are plaguing producers right now. Different weeds require different management strategies.
“Lets start in the spring. In a fumigated plasticulture production system, nutsedge remains the baddest boy that there is. That’s the only weed that can penetrate through the mulch. Nutsedge is still a huge dominant player. In addition to nutsedge, what has really taken its foothold on a lot of my guys has been purslane species and a lot of ours is actually pink purslane; a bunch of different grasses that have always been here and then our amaranth species (not palmer amaranth),” Culpepper said.
“If you look at this time of year, wild raddish is the baddest boy that there is.”
Weed Management
Weed management remains key to successful vegetable production, whether you are talking about now or in the spring. Before plants are ever put in the ground, weed control needs to be a top consideration for producers. Weeds challenge and can overwhelm crops for water, sunlight and nutrients.
Culpepper said in most situations, the weeds are better competitors than the crop.
“Before you ever start a conversation, you say, ‘Look, vegetable weed control is really challenging. There can’t be any weed emerge at planting.’ It’s very likely that if we’re going to implement a herbicide program we’ve got to start it before we ever plant,” Culpepper said.
“In transplanted onion production, obviously, very important to Georgia, we have an excellent herbicide program that will be successful probably 95-plus% of the time, which is really, really good. If you wanted to grow seeded onion production in the state of Georgia, I don’t think you’ll have a chance because you can’t manage the weeds. Or if you do, you’ll spend a tremendous amount of money.
“There’s the same crop per se grown two different ways; one is very unlikely to be successful and the other is very likely to be successful with regards to weed management.”
“If you wanted to seed cabbage, because of wild raddish, you’re in trouble. But if you want to transplant cabbage, I have a herbicide you can put out before you transplant, and I’ll take the wild raddish out.
“There’s two examples, exact same crop, of how you want to process or implement your program will determine how successful you’ll be.”
UGA CAES Photo/A survey conducted by UGA researchers examined whether respondents had any concern about the growing of hemp and the creation of hemp products in their area.
By Allison Fortner for CAES News
Hemp is a promising new industry for profitability, but growers of this newly legal crop will face a mix of public opinions according to University of Georgia research into challenges those in the hemp business may face in the southeastern United States.
A recently published article in the Journal of Agricultural and Applied Economics identified the concerns nearby residents may have with local hemp production and processing. The study was led by UGA College of Agricultural and Environmental Sciences faculty Benjamin Campbell and Julie Campbell in collaboration with Adam Rabinowitz at Auburn University.
“We got involved in doing hemp economics two years ago when it was passed with the legislature,” said Benjamin Campbell, associate professor and UGA Cooperative Extension specialist in the Department of Agricultural and Applied Economics. “We started asking if there would there be a negative perception or externalities associated with these hemp processors coming [into communities].”
With the passage of the 2018 Farm Bill, hemp was legalized as a crop in all states. Though hemp is not a novel crop, the legislation opened opportunities for markets in new areas and resulted in a fast push to produce and process the plant. The research team initially examined budgeting and markets surrounding hemp but found there was a lack of research in hemp production perception. They sought to identify potential problems that could arise in communities where the crop is grown and processed into various goods.
“We kept seeing people concerned about light pollution and the smell in popular press-type reports,” said Julie Campbell, an assistant research scientist in the Department of Horticulture.
The group put together a list of questions that was distributed via an online survey to southeastern U.S. residents. The responses were representative of the population, with consideration to household income, race, education level, age and gender.
Demographic Considerations
The survey examined whether respondents had any concern about the growing of hemp and the creation of hemp products in their area.
Researchers found that Republicans are 4.8% more concerned about hemp production and 4.9% more concerned about processing than Democrats. Therefore, the political landscape should be considered when hemp firms are garnering local community support.
The research also revealed that education level does not necessarily dictate the amount of concern. Respondents with a high school education or less and those with graduate degrees expressed more concern about local hemp production and processing than those with a bachelor’s degree.
“There’s not one consumer. There’s a whole various subset of consumers that believe different things,” Ben Campbell said. “Surveys allow us to understand these different groups and assess what their perceptions are. This helps us inform these groups so they can understand what’s going on with the new technologies.”
Differences Between Hemp and Marijuana
Though hemp and marijuana are identical in appearance, the determining difference between the two is the level of tetrahydrocannabinol (THC) present in the cannabis plant. THC is the chemical responsible for most of marijuana’s psychological effects, but its levels are strictly regulated in commercial hemp crops. Ben Campbell said a resulting concern is consumer belief that hemp is the same as marijuana, though smoking a hemp plant does not result in a high.
The survey collected information about consumer knowledge level and found that 44% of respondents thought that hemp and marijuana were the same, while 44% knew hemp and marijuana were different. The remaining 12% had never heard of hemp.
“For years there have been entire drug campaigns saying, ‘Marijuana is horrible.’ People associate hemp and marijuana as being the same thing. Now all of the sudden we’re saying, ‘Hemp is good.’ It’s kind of hard to have people turn on a dime,” Julie Campbell said.
While the plants have different chemical compositions, their matching appearance leads to concerns of illegal activity.
“You have people breaking into fields in other states and stealing hemp plants because they think it’s marijuana. That’s one of the externalities I was looking at — illegal activity,” Ben Campbell said.
The survey examined the perceived concerns of respondents and found that the potential for illegal activity and overall safety were the highest-rated concerns for both local growth and processing.
Therefore, engagement with communities to dispel myths about hemp and to educate about its benefits is crucial. These efforts should also address issues of local concern to help neighborhoods feel more comfortable with the hemp firms in their areas.
“I think it brings up a point that you need to have producers and processors interacting with their neighbors to show them what they’re doing and alleviate any concerns so that they are informed. If not, you’re going to have people believing that you’re hurting them or harming them when that may not be the case. That’s the biggest overall takeaway,” Ben Campbell said.
Future Research
Julie Campbell said this research provides a perspective on what hemp firms will need to consider before investing money and establishing themselves in a community, especially considering the government hearings businesses must go through for community input. However, she said communication and education on this matter will be up to both industry and academia.
“People growing hemp, people growing medicinal marijuana – it’s coming,” she said. “We have to be able to do research on this so that we’re not left behind. People are looking to the university for guidance on this.”
The questions and results from this study will inform future consumer surveys. Recently, Ben Campbell received a Federal State Market Improvement Grant from the U.S. Department of Agriculture (USDA), in collaboration with Auburn University, the University of Delaware, and the University of Kentucky, to conduct monthly consumer surveys over the next three years, allowing for further hemp research, among other public perception and marketing surveys.
Ben Campbell’s research and Extension efforts are devoted to better understanding the consumer marketplace for horticultural products, notably green industry products. He has more than 15 years of experience in conducting market and production economics research throughout the U.S. and Canada. His work has focused on market intelligence, market identification and the economics of production for varying horticultural commodities.
Julie Campbell’s recent research focuses on a number of issues facing the green industry, including consumer perceptions, marketing, disease mitigation and best management practices. Her research helps link consumers, retailers and producers, often intertwining multiple disciplines.
For more information on the UGA Department of Agricultural and Applied Economics Department, visit agecon.uga.edu. For more information on the UGA Department of Horticulture, visit hort.uga.edu.
The flurry of last-minute regulations from the Trump administration includes a final rule concerning domestic hemp production. The Department of Agriculture published the final rule notice in the Federal Register Tuesday. The U.S. Hemp Growers Association says the final rule appears to address many of the concerns the organization expressed during a comment period.
Changes include allowing a producer a maximum of one negligent violation in a growing season, but the threshold for finding such negligence is moved from .5% to 1%. Alternative disposal for non-compliant plants will be outlined in a separate remediation techniques paper from the USDA Agricultural Marketing Service. Disposal and remediation measures will be expanded.
Because there are not enough Drug Enforcement Administration registered laboratories to test all hemp in 2020 and 2021, non-DEA registered labs will be recognized for testing until Jan. 1, 2022. Sample collection is expanded to 30 days before harvest instead of the former 15 days.
(From the National Association of Farm Broadcasters)
Hemp plant diseases are present in University of Florida (UF)/IFAS research trials. But their impact has been minimal so far, says Johan Desaeger, Assistant Professor of Entomology and Nematology at the UF Gulf Coast Research and Education Center.
“So far, honestly, we haven’t seen too much in our trials here. We’ve seen some fungal diseases some leaf spot. We’ve seen some mites; we’ve seen some worms but nothing that I would say was really causing damage to the crop. Another thing we’ve seen is nematodes. They do get nematodes, but again, we haven’t seen so far any clear evidence of damage caused by the nematodes,” he said. “They feed on the crop. We know that. They’re a host for root-knot.
“Hemp, these plants, they put on so much roots that I feel they can kind of overcome the damage.”
Hemp research is still in its infancy stages, not only at UF, but at universities across the Southeast. Desaeger believes as more hemp is produced across the state, diseases will become more prevalent.
“I think they will show up eventually. I think we just haven’t seen much because we just started growing it. It often takes a few seasons and few years for these diseases and pests to come in when you start a new crop. The more we start growing hemp, I’m sure the more issues that are going to be reported,” Desaeger said. “I (also) think we’ll start learning a lot more when we have growers start to plant it in their fields. Most of the stuff we’ve done is on station, research trials, not really out there in the real world if you know what I mean.”
A cold and rainy winter has been challenging so far for Alabama vegetable producers. Joe Kemble, Alabama Extension vegetable specialist, cautions growers that though it may be chillier, that does not eliminate certain diseases that can be problematic.
“I will say on the vegetable side, things are a bit slow. Weather’s been not exactly ideal. The rainfall we’ve been having, I would be concerned about things like Anthracnose, leaf blights; things that cause leaf blights on greens,” Kemble said. “I’d say be diligent and keep an eye out because the weather, unfortunately, yeah it’s cold but the afternoons warming up and still in these 45, 50, 60-degree days, that is warm enough for some of these diseases to keep moving around.
“The cold weather does not eliminate that problem, unfortunately.”
Yellowmargined Leaf Beetle
Farmers also need to be wary of potential insect problems even during cold weather conditions, specifically with the yellowmargined leaf beetle. Unlike some insects that prefer summer, or warm conditions, the yellowmargined leaf beetle likes cooler weather and will impact brassica crops.
“It’s fairly new to our area the last few years. They’re incredibly hard to kill. If you’re growing cabbage, they can hide very well in the heads,” Kemble said.
“It’s really hard to get sprays sometimes on them. You’d be harvesting and start finding all of these holes in leaves and things. Unfortunately, the yellow margined leaf beetle is pretty good at what it does in terms of holes and things like that.”
The Georgia Department of Agriculture will host the Georgia Virtual Produce Safety Alliance Training on Jan. 26 and Jan. 27 from 8 a.m. to noon. The two-day workshop covers the standardized curriculum designed by the Produce Safety Alliance, which meets the regulatory requirements of the Produce Safety Rule under the Food Safety Modernization Act (FSMA).
Individuals who participate in this course are expected to gain a basic understanding of:
Requirements in the FSMA Produce Safety Rule and how to meet them successfully;
Microorganisms relevant to produce safety and where they may be found on the farm;
How to identify microbial risks, practices that reduce risks, and how to begin implementing produce safety practices on the farm;
and Parts of a farm food safety plan and how to begin writing one. (ers.usda.gov/arms): ers.usda.gov/arms
Stormy Sparks’ message regarding whitefly management remains the same: If you’re done with the crop, get rid of that crop.
Sanitation remains the best defense against whitefly buildup in Southeast vegetable and cotton crops. Even watermelon producers, who don’t have to contend with whiteflies as much as cantaloupe and cucumber farmers, are encouraged to do their part in preventing potential infestations in other fields.
“Watermelons present a unique challenge because we’re dealing with so many more growers,” said Sparks, a University of Georgia Cooperative Extension vegetable specialist.
“If you look at it from strictly a financial standpoint this season, in many cases there’s no emphasis on whitefly management in watermelons. But if we don’t get rid of the crop, we can distribute them on watermelons and then they can build up in those crops that are left standing and move into cotton. That’s basically what happens.”
Sanitation is a key management strategy all farmers can implement when managing whiteflies. Once farmers are done harvesting their spring vegetables, they need to get rid of them.
Watermelons Left in the Field
But in many watermelon fields, watermelons are sometimes left in the field long after the final harvest. This can be largely attributed to “pinhookers” or people who buy the remaining watermelons in a field with the purpose of reselling them. However, this leaves a watermelon field susceptible to whitefly infestations since so much of the crop is left in a field for weeks, if not months.
“You can find fields in the fall that were planted in the spring,” Sparks said.
Whitefly Impact
Whiteflies migrate from winter vegetables to spring vegetables to agronomic crops, like cotton, to fall vegetables and back to winter vegetables. Whiteflies cause feeding injury issues in vegetables and transmit two viruses: cucurbit leaf crumple virus and cucurbit yellow stunting disorder virus.
To be a farmer is to be an optimist. Farmers work long hours, deal with weather events, labor issues, trade issues and global pandemics that are beyond their control. The 2020 Florida blueberry harvest season was a tough one due to increased imports and the coronavirus pandemic. The government did provide some assistance to farmers through the Coronavirus Food Assistance Program, which will help them continue forward into the coming 2021 season.
WINTER WEATHER
Florida blueberry growers have hedged and regrown their bushes for the year. Fall season into winter is a time for flower bud development, which gives the first indication of the crop to come. It is too early to tell what size crop Florida will produce. The Florida industry has been pretty stable in production numbers (~20 million pounds) the last few years due to some decent amount of cooler weather in the late fall and early winter.
During the last warm (no chill) winter, the state struggled to produced 15 million pounds. This winter, climate forecasters are calling for a La Niña weather cycle. La Niña events are predicted to produce warmer temperatures and less rainfall than on average. The Florida blueberry industry has been moving to more evergreen production, which warmer weather tends to favor in terms of crop timing. A warmer winter most likely will not have quite the negative effect on statewide volumes like it has in the past.
November tends to be the slowest month in blueberry production. Most growers take a vacation, work on getting their overhead irrigation ready for cold protection and replant new or existing ground. Things start to ramp back up in December as plant growth regulators are typically applied to stimulate the plants into flowering in January.
In January and February, growers battle cold weather events during pollination. This leads to the setting of their berries that will be harvested in the spring. The spring brings hope of good yields with excellent quality.
MEXICAN COMPETITION
The unknown challenge this spring will be the ever-increasing Mexican blueberry volume during the Florida harvest window.
Mexican blueberry production has increased dramatically over the last decade. This has led to reduced prices and returns to Florida growers. Many Florida blueberry farms have thrown in the towel the past several years. Others have turned from commercial to u-pick operations.
The American public is growing more aware of the increase in foreign food supply. As U.S. consumers become more aware of this, the #DemandAmericanGrown campaign will continue to gain traction. We as agricultural producers need to continue (or start if you have not already begun) to educate our fellow Americans on the importance of American agriculture.
What happens if our country were to become dependent on a foreign supply for food? We would be at the mercy of those who produce that food. This seems absurd to many Americans, as food is relatively abundant for most of our population. However, one only needs to look at socialist countries such as Cuba, Venezuela and others to see the effects of a short food supply.
America was built on its great agricultural history. If we want to continue to be a great country, we need to be committed to local agriculture. It is a matter of national security.
Ryan Atwood is co-owner of H&A Farms in Mt. Dora, Florida
