How’s It Looking? Clemson Extension Agents Provide Crop Updates

Clemson Extension agents provide updates in The South Carolina Grower this week about the status of various crops being produced throughout the state.

Statewide

Tom Bilbo (Extension Entomologist)

• As our late-summer and fall plantings get under way, keep in mind two cucurbit insect pests that worsen around this time: whiteflies and caterpillars (specifically, melonworms and pickleworms).
• Whiteflies: I’ve been seeing whitefly-induced leaf silvering which is NOT to be confused with either powdery mildew or some of the squash cultivars that naturally have some silver spots. Whitefly silvering tends to be more uniform across the entire leaf surface. Natural cultivar silvering manifests more as isolated angular blotches along the veins. Powdery mildew looks like white powdery spots. See more pictures comparing silvering here.
• Caterpillars: Melonworms and pickleworms can cause a lot of damage quickly if fields are left untreated. The best approach currently is insecticide applications BEFORE caterpillars tunnel into flowers, fruit and stems. Once here, foliar sprays cannot reach them.
• Insecticide selection: Strategic selection of insecticides is important when dealing with multiple pests since there is some overlap in target pests. Table 2-25 in the SE Veg Handbook is a great resource for this. If you have both whiteflies and caterpillars, then Exirel and Rimon are good options. Note that stink bugs, leaffooted bugs and squash bugs are best managed with pyrethroids (e.g. Brigade) or neonicotinoids (e.g. Venom), but overuse of these is detrimental to both pollinators and natural enemies and can make whitefly problems worse.

Coastal Region

Anna Sara Hill

•  Hurricane Debbie slowly crawled up the east coast dumping a lot of rain. By mid-afternoon on Monday the rain had set in across Barnwell, Bamberg, Allendale and Hampton. It didn’t let up until early Wednesday. There were some spotty showers in the region Wednesday and Thursday. By Friday things were drying out.
• Damage assessments will be ongoing this week. In addition to flooding and wind damage, be on the lookout for disease and insects. As soon as it is safe and possible to get into the fields to scout and spray, please do so. If you have questions, concerns or need assistance, please call your local Extension agent. We are happy to help.
• There is flooding along low-lying areas near rivers and swamps. Many fields are waterlogged. Most of the standing water has resided, but areas are still boggy. Use caution when going into fields before they have dried out. They can be damaged by equipment causing ruts and increasing compaction.
• Humidity has been extremely high the past couple of days, causing dense fog in the mornings. 
• Some safety tips for dealing with high temperatures and humidity include staying hydrated by drinking a lot of water, taking frequent breaks in the air conditioning, wearing light-colored and loose-fitting clothing, limiting sun exposure and remembering the sunscreen.
• Be aware of your body’s warning signs and tell someone or get out of the field, if you start feeling bad. Some early warning signs to watch out for are increased sweating, the feeling of a weight on your chest, difficulty breathing, weakness and fatigue, racing heart and dizziness. Take precautions to ensure that you and your employees stay safe.

Zack Snipes

• We are extremely saturated. The lowest rainfall total I have seen is 8 inches. I have heard reports of 20, 14, 12 inches from around the region.
• Luckily, we don’t have too many crops in the ground right now. We lost some hot peppers, pumpkin, cantaloupe, and probably some yield on fall watermelon, but time will tell.
• Everything is extremely saturated. Ditches are full, and we can’t get into the field to work. Might be a while before things dry out as the inland deluge of water will make drying out difficult.
• I am getting pictures from growers with cucurbit fields that are not looking great due to the stress of 20 inches of rain, coupled with downy mildew and gummy stem blight taking their toll in fields where we can’t get in to spray.

Midlands

Rob Last

• In my area of the Midlands, we have observed a lot of steady rain with no damage observed from wind.
• All of our soils are at field capacity and potentially over saturation point. These conditions can lead to hypoxia (a lack of oxygen in the soil). Hypoxia symptoms include chlorosis of the lower leaves starting in the center of the leaves, premature leaf drop and wilting. Hypoxia can be easily confused with nutrient stresses.
• Given the abiotic stress, rain splash and humidity, monitor closely for diseases, both bacterial and fungal. Fungal and bacterial active compounds would be beneficial as soon as we can travel. If you have any questions, please reach out to us.

Sarah Scott

• Last week was definitely wet, however, most areas of Aiken and Edgefield Counties avoided flooding rainfall from Tropical Storm Debby. Parts of the lower end of Aiken County received 8 inches of rain, while areas of Edgefield saw only 1 or 2 inches. Although we did not flood, several days of wet weather made field conditions difficult and delayed growers.
• Growers worked to get protective fungicide sprays out in peach orchards prior to the rain to help slow the spread of disease, such as bacterial spot and brown rot. Both are on the heavier side at this point in the season. If growers suspect fungicide resistance to brown rot, samples can be taken by your local Extension agent and sent for testing.
• Peach harvest will likely continue for a few more weeks as the season is starting to wind down. Some late summer pruning is taking place along with trunk spray applications for borers.

Pee Dee

Christiana Huss

•  Many fields were partially or fully underwater for several days last week, especially in swampy regions along the rivers and closer to the coast. Farmers have been busy digging trenches to drain fields. Over the weekend, much of the flood water receded, but we expect more rain throughout the week. I’ll know more details about Debby’s impact later this week now that I can safely resume field visits.

Brittney King

• The Pee Dee received varying amounts of rain last week as Tropical Storm Debby passed over us. Some areas received up to 10 inches of rain within four days and others around 4 to 6 inches.
• Muscadines are showing fruit split from the excess rain, and I saw a couple of watermelon fields that were partially flooded. Regarding crop loss, thankfully, most growers had empty fields or could get a final harvest before the storm. I have not heard any reports concerning that.
• The main issue I hear from growers is that the soil is too wet to prepare for and plant fall crops. Plants are getting too big to fit through transplanters while we wait for the ground to dry out.
• A few growers said they could get fungicides sprayed before the storm came. For those that didn’t, I recommended getting out there and spraying before we get another rain. Please refer to the Cucurbit Downy Mildew Management article for fungicide recommendations.

Upstate

Andy Rollins

We are having very large stinkbug populations in the Upstate, primarily brown marmorated stinkbugs. They were doing damage to okra on this farm, causing bumps on the fruit and making it less marketable. Multiple insecticides would control this pest. I like combining a pyrethroid with a neonicitinoid like imidacloprid. It has a 0-day PHI when applied foliarly.  

Peaches are still doing well. We are picking Flameprince and finishing up Ohenry. We have had to treat for San Jose scale on several farms. Previous spider mite problems have subsided with applications of Acramite. Growers are now getting ready for borer sprays. Some have leftover stock of Lorsban they will be applying. Other options are available as well.