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 preplant fertility and herbicides are critical to spring success. Spartan and Devrinol  are the only two preplant 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.
Adult diamondback moth that just finished pupating on a collard leaf. 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 has 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.

Weekly Field Update – 9/28/20

Coastal

Zack Snipes reports, “Cooler temperatures have really helped out the direct seeded fall crops.  Carrots, beets, and arugula are looking great around the Lowcountry.  We had about 2 inches of rain so many fields are soggy.  I am still seeing high numbers of whiteflies on just about every crop.  Whitefly feeding will lower yields so make sure to scout the underside of leaves. I expect to see an increase of disease, particularly downy mildew on cucurbits and black rot on brassicas with the cooler temperatures and abundance of moisture.”

Arugula is looking great in this cooler weather. Photo from Zack Snipes.
Whitefiles on the underside of a cucumber leaf which will cause yield drags. Photo from Zack Snipes.

Midlands

Justin Ballew reports, “It’s been cooler this week and we got a little rain from the remnants of Beta. Its been several days since we’ve seen the sun, also. Lots of brassicas are being harvested now and more are being planted. There is a little black rot out there and plenty of caterpillars still. Strawberry plastic has been laid in a number of places and planting is just right around the corner.”

Strawberry plastic being laid in the Midlands. Photo from Justin Ballew.

Pee Dee

Tony Melton reports, “Too wet to plant greens or harvest sweet potatoes & peas.  Peas are falling down reducing yield due to the inability to combine harvest.  Sweet potatoes are beginning to rot due to the wet soils reducing yields and quality.  Farmers are having to mud through fields to harvest pickles.  Downy Mildew, Pythium leak, and belly rot are bad!”

Upstate

Kerrie Roach reports, “With the end of September, most all the local farmers markets are finishing up for the season. Online markets and specialty/holiday markets will continue, but many produce growers have finished production until spring. Apples are continuing to be about 2 weeks ahead of schedule with decent crops across the board. Some growers have experienced high rates of fungal pathogens just because of the high rain incidence.” 

‘Brooks Spot’ preliminarily identified on Granny Smith apples. Photo from Kerrie Roach.

Weekly Field Update – 9/21/20

Coastal

Zack Snipes reports, “Cooler temperatures have finally arrived in the Lowcountry!  We had a good bit of rain in certain areas last week and some fields are soggy.  I saw lots and lots of silverleaf disorder in squash this past week.  Silverleaf disorder is caused by whiteflies.  The nymphs of the whitefly feed on the newly developing tissue which causes the upper epidermis of the leaf to separate thus giving the plant a silver appearance.  I am still seeing heavy whitefly pressure in most crops throughout the Lowcountry so keep up with spray programs and remember to ROTATE chemistries. For more information on the whitefly, click here.

Silverleaf of squash is a symptom of whitefly feeding. Photo from Zack Snipes.
Whitefly feeding damage on collards. Photo from Justin Ballew.

Midlands

Justin Ballew reports, “These cooler temperatures that have arrived following the rain feel great, but they are going to slow crop development some. Folks are already picking fall brassicas, though some may be a little small. Just trying to keep up with demand. There are plenty of caterpillars out there. I’m seeing diamondback moths (of course) as well as cabbage loopers and a few corn earworms. Be sure to rotate your insecticides when spraying for caterpillars. Folks are continuing to prep fields for the rapidly approaching strawberry season.”

Cabbage loopers are showing up. Loopers frequently rear up like a cobra when disturbed. Photo from Justin Ballew

Sarah Scott reports, “Heavy rains, in some areas totaling near 6 inches, fell around Aiken and Edgefield Counties last week. Rain was definitely welcome, however, the downpours led to some erosion issues as well as waterlogged soils in low spots. Brassica crops are benefitting from the cooler temperatures. Peach season has ended and post-season cleanup has begun. Plastic has been laid for fall plantings of strawberries.”

Eggplant is looking good. Photo from Sarah Scott.

Pee Dee

Tony Melton reports, “Rain, rain, rain. It came quickly, so most drained off quickly, if drainage was adequate.  Need to dig sweet potatoes as quickly as possible to keep down the amount of rot.  Greens, pickles, and peas are struggling to survive the rain – some are drowned.  Ponds are back in the fields.  Some strawberry plastic is already down but the rest of the folks are just beginning this week.  Transplants are scarce and most likely will be late getting here this year. 

Upstate

Kerrie Roach reports, “There has been a significant rise in wine grape production interest over the last month or two in the Upstate. Each week seems to bring another caller asking for recommendations. While climates here are relatively good for grape production overall, high humidity and heat make disease control difficult. Pierce’s Disease is one of the deadliest to deal with; prevention requires intense insect vector control and control means the complete removal of the affected plant. Recent studies have brought new cultivars to the forefront which are helping southern growers become more successful in this niche industry.

‘Traminette’ with leaf scorch symptom of Pierce’s Disease. Photo from Kerrie Roach.
‘Traminette’ with a dead leaf petiole still attached to the vine. Another symptom of Pierce’s Disease. Photo from Kerrie Roach.
‘Traminette” with Pierce’s disease showing islands of green tissue surrounded by brown. This specific grower has already disposed of the affected vines, and will be replacing with newer more resistant cultivars. Photo from Kerrie Roach.

Weekly Field Update – 9/8/20

Statewide

Dr. Matt Cutulle reports, “With all the rain we had in August the weed seed bank is starting to pop. Nutsedge pressure can be really tough in September.  For fall cole crop plantings, it is important to initiate the stale seed bed technique (allow weeds to come up and burn them down multiple times before planting). In some cole crops, such as broccoli, Dual Magnum may be used, which provides some pre-emergent suppression of yellow nutsedge (Max 60% probably). Following with an in-row cultivation several weeks after planting will strain the photosynthate reserves of nutsedge, which could be lethal to the nutsedge if we get a  cold snap in late October.”

Coastal

Zack Snipes reports, “I saw whiteflies everywhere last week.  I saw them on just about every crop in the field: squash, zucchini, tomato, peas, eggplant, okra.  We have very good options to manage whiteflies, so consult with your local agent or look up the specific products for the crop you are growing in the Southeast Crop Handbook. Be careful not to use pyrethroids for whiteflies as resistance will develop very quickly.  Longer lasting, more specific options are available that are better options.  I also saw a good many worms last week such as the melonworm in cucurbits and the beet armyworm in other crops.  If you have whiteflies and worms in a crop then the group 28 insecticides (Coragen, Verimark/Exirel, Harvanta) are excellent options to take care of both pests at the same time with good residual.”

Whitefly infestations are severe in some places on the Coast. Photo from Zack Snipes.
Whiteflies on tomato leaves. Photo from Zack Snipes.

Midlands

Justin Ballew reports, “Last week was extremely hot and dry, though we finally got some relief from the heat over the weekend. Crops are progressing well, though we are seeing caterpillar activity increase. We’re seeing diamondback moth and cabbage loopers in brassica crops and armyworms in tomatoes. Be sure to rotate insecticide MOA’s when treating for caterpillars. I’m also seeing a few whiteflies around, but nothing severe yet. Black rot is starting to show up on some brassicas. Strawberry growers are starting to apply their preplant fertilizers in preparation for shaping the beds.”

Black rot getting started on a young collard plant. Photo from Justin Ballew

Pee Dee

Bruce McLean reports, “Muscadine harvest is starting to wind down. Harvest looked good and had very good yields. Brix averaged out at 13.5 to 14.5%, depending upon the cultivar and the vineyard. Now is a good time to evaluate successes and problems from this season and write them down while they’re fresh on your mind. Also, look at the overall amount of foliage on the vines. Is it too much? Not quite enough? Start planning how you need to adjust fertility for next year. A post-harvest potassium fertilizer application has proven to be beneficial to the crop (in on-farm settings), especially in wet years. Overall plant health, spring emergence and vigor, and next year’s yields should be well improved.”

A bin of Carlos muscadines ready to be loaded and delivered for processing. Photo from Bruce McLean.

Tony Melton reports, “Getting dry and need some rain. Busy planting turnips, mustard, and collards. Harvesting processing sweet potatoes as quickly as they can process them (problems in the plant). Picking pickles and yielding much better with dryer conditions. Also, pickling plants having trouble with getting enough labor so very few peppers harvested. Still spraying processing peas for cowpea curculio. Watch out for southern stem blight it is still raging havoc.”

Upstate

Kerrie Roach reports, “The last few peaches are making their way to stands and markets. Things are continuing to look good as the Apple crop progresses in the upstate. Growers to the north in Hendersonville, NC suffered multiple hail events causing a large amount of damage, but SC growers seem to have escaped the worst of it. Vegetable production has slowed significantly with many small growers finishing for the season over the next few weeks. Muscadines are coming into their prime, and look to be highly productive this year.”

Golden Delicious apples that still have a little ways to ripen for optimum sugar content, but work great for baking. Notice the green tint. As they continue to ripen, a yellow cast & even a blush may appear. Photo from Kerrie Roach.

Andy Rollins reports, “These plants were found positive for Phytopthora root rot last week in an early upstate strawberry planting.  Inspection of plants when they arrive can accurately diagnose this problem.  Brown to blackish colored roots are characteristic.  A small portion of this material is taken from 5-10 plants then placed into a pouch that accurately identifies the presence of Phytopthora within a few min.  As in picture, 1 line tells you the test worked properly 2 lines indicates presence of the fungus.  Early treatment with Ridomil and or any of the phosphite (Rampart/Prophyt) is very helpful but must begin quickly if plants are widely infected for the best results.”

Dark colored roots are a characteristic symptom of Phytophthora root rot. Photo from Any Rollins.
An immunostrip test can be used to diagnose phytophthora. Two horizontal red lines on the strip (right side of the bag) means the sample is positive for phytophthora. Photo from Andy Rollins.