Question of the Week: Corn Earworm

Last week the question was:  Which caterpillar is feeding on this soybean leaf?

IMG_20160803_094417147

This is a corn earworm.  The distinguishing features include 4 pairs of abdominal prolegs, black spots, and fine hairs all over the body.  Identification can be tricky, though, because corn earworms look exactly like tobacco budworms.  The only way to tell the difference is by looking at their mouthparts under a microscope.  The adults are much easier to tell apart.  take a look at Clemson Entomologist Jeremy Greene’s latest Cotton and Soybean Insect Newsletter for more information.  There’s a great graphic on the 4th page showing how to identify caterpillars.

 

Here is this week’s question:  Why is the larger grasshopper giving a piggyback ride to the smaller one?

IMG_20160726_080343461.jpg

Posted in Question of the Week | Tagged , , , , | Leave a comment

Asian Soybean Rust Found in SC

FROM:  John Mueller, Extension Soybean Pathologist, Edisto Research and Education Center

RUST WAS FOUND LAST WEEK ON SOYBEAN IN SOUTH CAROLINA IN A FIELD IN COLLETON COUNTY

Last week rust was found in a field in Colleton County.  We have agents actively surveying in several other counties in the Savannah Valley.  Here are this week’s results:

Joe Varn, Barnwell/Bamberg Ag agent returned to the “rust” field in Colleton County on Tuesday August 23rd and collected another 100 leaves.  He found rust on only 2 leaves and again there were only 1 or 2 pustules present on the leaves.

Joe also checked a second field yesterday in Colleton County.  He collected and examined 50 leaves but found no rust.

Andrew Warner, Allendale/Hampton Ag Agent collected leaves from two fields last week.  He collected 25 leaves from a field at R-3 growth stage in Hampton County but found no rust.  He also collected 25 leaves from a field at R-4 growth stage in Allendale and found no rust.

Andrew checked 40 leaves from a second field in Allendale yesterday that is at R3 growth stage but found no rust.

Jonathan Croft, Orangeburg County Ag Agent checked three fields last week.  He checked 100 leaves from a field at growth stage R4 in Orangeburg County but found no rust.  He collected 100 leaves from a field at R5 growth stage in Dorchester County and found no rust.  He also collected 100 leaves from a field at R5 near Bowman and found no rust.

So, of the seven fields we have been checking on an almost weekly basis we have found only 1 field with rust and the level of rust in that field is very low.  At this time, rust has not been found in the Pee Dee region.  This week’s weather for the most part is not conducive to spore germination or disease spread.  Rust develops best when we have morning dews that last up to 9:30 or 10:00 or even later and/or we have overcast days and rain.

If you would like an update on the occurrence of soybean rust across the United States check out http://sbr.ipmpipe.org .

Posted in Disease, Soybeans | Tagged , , , , , | Leave a comment

Question of the Week: Whiteflies

Last week the question was:  What is this on the underside of this cotton leaf?

IMG_20160809_091216557

These are whiteflies.  Whiteflies are similar to aphids in that they are piercing/sucking insects and feed on the sap within plants.  They excrete honeydew as they feed, also like aphids.  If populations are high, feeding damage can cause wilting and stunting of the plants.  Whiteflies are rarely a problem in cotton because natural enemies do a good job of controlling them.  For more info, take a look at pages 102 and 113 of the SC Pest Management Handbook.

 

Here is this week’s question:  Which caterpillar is feeding on this soybean leaf?

IMG_20160803_094417147.jpg

Posted in Question of the Week | Tagged , , , , | Leave a comment

Pee Dee Region Upgraded to Incipient Drought Status

Rain has not come quite as regularly in the Pee Dee as it had been earlier in the summer.  As a result, the SC Drought Response Committee has decided to upgrade the drought status to “incipient” for Kershaw, Chesterfield, Marlboro, Darlington, Lee, Florence, Dillon, Marion, Williamsburg, Georgetown and Horry Counties.

IMG_20160817_123756313.jpg

Cotton wilting from our recent dry spell.

The Pee Dee region has had a much easier summer than other parts of the state, but it seems we are not escaping the dog days of summer completely.  In the last two weeks we’ve seen a number of cotton and soybean fields showing signs of water stress.  Cotton has started shedding squares and smaller bolls in response to the hot, dry weather.

The Pee Dee joins most of the state in the incipient stage of drought and there are now 7 counties in the moderate stage (the second stage).

FullSizeRender

You can read the Drought Status Press Release in it’s entirety here:  DroughtStatusPressRelease_Aug1716

There is some rain in the forecast over the weekend.  Let’s hope we get enough to perk up our fields for a while.

Posted in Uncategorized | Tagged , , , , , | Leave a comment

Cotton Marketing News – 8/12/16

FullSizeRender.jpg

Image | Posted on by | Tagged , | Leave a comment

Question of the Week – Stinkbugs

Last week the question was:  What caused the wart-like growth on the inner wall of this cotton boll?

IMG_20160803_103709918

This is classic stinkbug damage.  When we see this, we frequently see discolored lint also.  It’s nearly impossible to tell whether you have stinkbug damage unless you tear apart some bolls and look inside, so proper scouting is key.  For information on scouting and thresholds, check out page 112 of the SC Pest Management Handbook.

 

Here is another cotton related question for this week:  What is this on the underside of this cotton leaf?

IMG_20160809_091216557.jpg

Posted in Question of the Week | Tagged , , , , | 1 Comment

Peanut Update – 105 DAP

The following update was prepared by Clemson peanut specialist Dan Anco.

For peanuts that were planted May 1, we are coming up on the 105 DAP mark. We’ve been getting some decent rain recently that should help with pod fill for peanuts that we dry earlier. Hopefully we get what we need there and then get enough dry weather when it comes time for digging and combining.

Seeing Spots:  This is a good time to take a close look at how much leaf spot we might have in different parts of the field. The best way to do this is to bend the plants back to be able to see all the way down to the bottom of the canopy. Often times late leaf spot gets started down in the bottom and works its way up from there.

Late leaf spot.jpg

Late leaf spot.

Late leaf spot typically shows up dark brown, with the best indication that it is late leaf spot being the presence of tiny raised bumps (spores) within the spot on the underside of the leaf. A hand lens helps make it easier to see. Chemical burn can show up differently, and one of the ways it shows up is a spot with a lighter gray/brown center. Chemical burn spots do not have raised spores.

Chemical burn on left and late leaf spot on right.jpg

Chemical burn on the left, late leaf spot on the right.

 

 

Always a good idea to look at all the varieties, even Bailey. If we start seeing disease buildup, this time of year when the canopy is bigger it may be good to think about using a product with systemic activity (most premium products have systemic activity, check the Production Guide for more details). This helps when complete surface coverage might be difficult in thick canopies. If maturity and weather cooperate, the 105 DAP spray may be the last one for Virginia types. Runner types typically will have at least one more. When possible, it can be a good idea to include Bravo (chlorothalonil) in the last spray of the season. This can help reduce fungicide-resistant populations from surviving over into the next year.  Here are some more leaf spot photos:  Leaf spot pictures

Foliar Feeding:  When seeing signs of feeding on peanut leaves, a lot can look similar. Because of this, it is always best to be able to get a positive identification on an insect pest before we spend time and money putting out an insecticide that may or may not be best for each individual situation. That being said, sometimes we can get a hint at what might be going on by taking a look at the damage on a leaf. If we see feeding damage at random places on the leaf, that doesn’t tell us much. However, if the feeding damage looks like it is symmetrical (damage looks like the same shape to the left and right of the main mid-vein of each leaflet, see attached pictures), that is an indication that the feeding took place at night when the leaves are folded.

20160812_085215.jpg

Symmetrical damage on either side of the leaf from night time feeding damage of the granulate cutworm.

The granulate cutworm likes to feed at night (when the leaves are folded) and hide in soil or under fallen leaves and plant litter on the ground during the day. This doesn’t mean granulate cutworm is always to blame when we see symmetrical damage, but it does give us a possible clue about where we also need to be looking. Again, always best to get a positive ID on what is causing the damage before selecting a product to use. See the Production Guide for product recommendations. Typical feeding defoliation thresholds are about 20 – 25% defoliation.

Posted in Peanuts | Tagged , , , , , , , | Leave a comment

Cancellation of Flubendiamide (Belt) Upheld

The EPA’s Environmental Appeal Board (EAB) upheld the EPA’s decision to cancel the registration of the insecticide flubendiamide – Bayer’s Belt.  Belt was previously labeled on soybeans, peanuts, corn, cotton, and several vegetable crops for the control of caterpillars.

The EAB did not uphold EPA’s existing stocks determination and will allow distributors and retailers to distribute and sell any remaining flubendiamide inventories, and allow growers to continue use of the product according to label directions for use.

Here is a link to the EPA’s website with information regarding the cancellation of flubendiamide.

Posted in Pesticides | Tagged , , , , , , , , , , , , , | Leave a comment

Question of the Week: Blossom End Rot

Last week the question was:  Whats wrong with this tomato?

IMG_20160621_101255556

Blossom end rot occurs when there is a localized calcium deficiency in the fruit.  Blossom end rot does not necessarily mean there is a calcium deficiency in the soil.  Instead, it usually means the plant is not receiving regular watering, making the plant unable to transport calcium to the fruit.  The best way to reduce blossom end rot is to make sure your plants are getting regular and adequate water.

 

Here is this week’s question:  What caused the wart-like growth on the inner wall of this cotton boll?

IMG_20160803_103709918.jpg

Posted in Question of the Week | Tagged , , , , | Leave a comment

Southern Rust Finally Shows Up

Southern rust was found this week in Dillon County.  Though this would normally be a concerning disease, it has come so late that few growers will have to worry much about it.

IMG_20160802_085826496.jpg

Southern rust pustules.

The vast majority of our corn is either at black layer or will be there in a matter of a few days.  Southern rust is of no concern to these fields.  The youngest fields that are still at the halfway point  on the milk line (we have very few) are the ones we need to worry about.  In one of his previous disease updates, Clemson grain specialist David Gunter recommended an application of something cheap like tebuconazole if you were at 50% milk line when Southern rust showed up.  If you’re at 75% milk line or more, it probably isn’t worth spraying.  The rust isn’t very severe out there right now and you’re getting very close to black layer.

IMG_20160628_142628882_HDR.jpg

Dryland corn from 2016 season.  Vast improvement over 2015.

We have had a pretty easy season in most of the Pee Dee and we have a great crop out there right now.  The hot, dry weather we saw last week dried down some fields quickly and allowed for a few acres to be harvested.  A few people have asked about aflatoxin recently.  We shouldn’t expect to see nearly as much as we did last year since the season hasn’t been nearly as stressful.  A few ears have been found with some Aspergillus present, but nothing serious.

Posted in Corn, Uncategorized | Tagged , , , , , , | Leave a comment