Field Update – 7/27/20

Coastal

Zack Snipes reports, “It has been a hot week in the Lowcountry. Most spring and summer crops have finished up. Ground is being prepared and planted for fall crops. I have received a few texts from growers that have yellow dots on their zucchini plants, which is downy mildew. Even in this heat downy can still be an issue. I have also had some reports of green-colored squash in fields which is an indication of a viral pathogen. The crop handbook has recommendations for cultivars that are resistant to these viruses that cause this discoloring. Fall is notoriously bad for cucurbit viruses so plan accordingly.  I have also seen some flea beetle damage on crops as of late.”

IMG_6219

Downy mildew looks a little different on zucchini and pumpkin than it does on cukes. Photo from Zack Snipes.

IMG_1234

Flea beetle feeding damage on blackberry foliage. Photo from Zack Snipes.

Midlands

Justin Ballew reports, “It’s been hot in the midlands and we’ve gotten to the point where there isn’t much relief at night. We had some scattered rain throughout the week, but overall we’re still quite dry. Lots of land is still being prepped for fall crops. We’ve had some fall brassicas and cucurbits planted already and they’re looking good so far. Last week I got to watch a pecan grower in Lexington thin some pecan trees. Without thinning, he would have seen a massive yield this year, which would result in a significantly diminished yield next year. Pecan growers aim for nuts on just 70% of the terminal buds.”

20200723_101151

Fall squash seedlings just beginning to emerge. Photo from Justin Ballew

Thinning pecans with a mechanical shaker. You can see the nuts fall as the tree vibrates.

Pee Dee

Tony Melton reports, “Pickles are still being harvested and planted. We still have hundreds of thousands of bushels in contract to be planted and harvested.  Peas for processing are being rapidly harvested and replanted, some seed is short.  Sweet potatoes are starting to swell and size.  Processing peppers are being harvested but we have a shortage of labor and multi-millions of lbs. left to harvest.  Processing tomatoes will be finished harvest this coming week.  Spring planted fresh market butterbeans and peas are mostly harvested but seed is short to plant the fall crop. Still have some flooded fields and drowned crop.”

Upstate

Kerrie Roach reports, “Spotty rain across the county again last week has led to continued issues for growers without irrigation. Fall planting for vegetables is in full force. Peaches are looking good, and apples are coming along. Most growers will be putting on a fungicide cover spray this week before significant rains are forecasted.”

k1.jpg

Reverted apple rootstock (believed to be M7) volunteer tree with aborted fruitlet. Photo from Kerrie Roach.

Andy Rollins reports, “Bacterial speck and bacterial spot of tomato are major problems in plum tomato varieties in the upstate right now.  They were not able to control this disease even with a vigorous spray program using mancozeb + copper on several farms.  In nearby plantings of large fruit varieties, the disease is present but not a problem.  Samples have been sent to researchers at Auburn University where the have confirmed the presence of copper resistant isolates from other farms.  Call on your extension agent for assistance with identifying and controlling this problem.”

IMG_1736

Bacterial speck on a tomato leaf from the upstate. Photo from Andy Rollins.

Field Update – 7/20/20

Statewide

Dr. Matt Cutulle reports, “It is always good to control goosegrass even if it is past the critical period for competition with the crop. Lack of late-season control made hand-harvesting tomatoes difficult in the field pictured below. Also, there will be a huge deposit of goosegrass seeds into the soil seed bank for next year unless the seeds are destroyed after the harvest.”

c1

Late season goosegrass growth can make harvest difficult and contribute lots of seed to the seed bank, which will have to be dealt with in future crops. Photo from Dr. Matt Cutulle.

Coastal

Zack Snipes reports, “We experienced a nice hot week of weather in the Lowcountry.  Most crops are finishing up with the heat and recent rains.  On later season tomato I have seen bacterial leaf spot on the fruit which makes fruit unmarketable.  I am seeing this on the second cluster of fruit set and not on the first or third clusters.  Hemp seems to be off to the races and looking pretty good so far.  There are within every hemp field occasional wilted, stunted, and yellowed plants.  These plants always have a weak root system and most of the time have girdling and interveinal discoloration.  Peppers and eggplants are loving this heat and are producing in high volumes.”

IMG_1183

Bacterial leaf spot showing up on the second set of fruit on the tomato plant. Photo from Zack Snipes. 

IMG_1172

Wilting of hemp is very common and often sporadic throughout fields. Photo from Zack Snipes

Midlands

Justin Ballew reports, “Last week was hot and mostly dry, though we did have some scattered thunderstorms come through over the weekend. Field prep for fall crops continues. We’ve had some fall tomatoes, peppers, and brassicas transplanted already and more to come this week. Everything is growing pretty fast right now and we’re still picking spring crops. Keep an eye out for spider mites, as they love the hot, dry weather we’ve had lately.”

20200714_103102.jpg

Fall tomatoes transplanted in Lexington this past week. Photo from Justin Ballew

Sarah Scott reports, “We are still ahead of schedule on peach varieties being harvested.  Early August Prince and August Prince are being picked now which is over a week earlier than usual. The fruit quality is still good with slightly smaller than ideal fruit.  With the extreme heat and lack of rain in the past week, summer crops like tomatoes and cucumbers are looking rough. Bell peppers are doing well.”

20200709_155631

An Edgefield County grower assessing his Early August Prince orchard. Photo from Sarah Scott.

Pee Dee

Bruce McLean reports, “Sweet potatoes are looking good. Establishment seems to be very good for the most part. Long green cucumbers, yellow squash, zucchini, cantaloupe, peas, okra, and sweet corn are harvesting well. Condition is good to very good. Sweet corn will be wrapping up shortly. Blueberries are pretty much finished, with only a few remaining fruit on Powderblue. Fruit condtion is fair to good. Muscadines are coming along nicely and appear to have an excellent crop. Fresh muscadines should be beginning harvest soon, with wine/juice grapes still a few weeks from harvest. Be on the lookout for Grape root borer moths. They are starting to emerge. They were being caught in traps placed in vineyards in Marion and Horry counties.

b1

Grape root borer moths being caught in a bucket-style trap. Photo from Bruce McLean.

b2.jpg

No, this is not a paper wasp. It is a grape root borer moth. Photo from Bruce McLean.

Tony Melton reports, “Harvested first crop of processing peppers. Continuing to pick and plant pickles. Processing greens are over for the spring crop. Harvesting the first crop of processing and seed peas and planting fall crop.  Getting processing tomatoes out of the field as quickly as the plant can take them.  Things are drying out, hope we don’t go into drought with the heat.”

Upstate

Kerrie Roach reports, “Spotty rain and high temperatures have left many small growers scrambling for irrigation options throughout the Upstate. Peaches and nectarines are still being harvested. Blueberries are just about finished, and farmers’ market produce is starting to wind down with the heat. Apples should begin next week with early varieties like ‘Ginger Gold’  and ‘Golden Supreme’.”

Andy Rollins reports, “Plenty of early blight, bacterial spot/speck on tomatoes this season, but some of the more troublesome problems have been various tomato virus problems. When diagnosing virus problems it is important to get lab verification because herbicide injury can look very similar when just going by visual symptoms. If you suspect herbicide drift from a neighboring farm. Look for damage to other broadleaf plants in the area in between the suspected source and the damaged plants. Follow the wind direction.  You should have more severe damage on the leading edge. Also, herbicide residual from a previous crop like sunflowers can also give you herbicide damage that you did to yourself. Read and follow all pesticide label directions. There are plant back restrictions on some herbicides so be careful. If this is the case the damage should be fairly consistent/uniform throughout the area that was planted in the other crop.

Unlike both of these other situations, virus problems may come from your seed source, the greenhouse where plants were grown, or from weeds in the field. Pokeweed is commonly a source, as are many other broadleaf weeds. Thrips, aphids, and whiteflies are all known to vector viruses into plants. Symptoms are what you see below with “shoestring” looking leaves, leaves with distorted veins, and mosaic yellow and green coloration. There are many viruses that infect plants. Each of them can show different symptoms and also they can each look different on other plants as well. It’s even possible for a healthy-looking plant with no symptoms to be infected with several viruses.”

IMG_1603.jpg

“Shoestring” type leaf distortion may be a symptom of a virus or herbicide damage. Get confirmation from the plant disease lab. Photo from Andy Rollins.