Question of the Week: Braconid Wasp

Last week the question was:  What are the white things on this strawberry leaf?

IMG_20170516_105429121

These are braconid wasp pupae.  Braconid wasps are beneficial insects that we love to see in our fields and gardens, though they are mostly so small that they go unnoticed.  Braconids are parasitic wasps that parasitize a wide range of insects.  There are a huge number of species that specialize in parasitizing aphids, caterpillars, beetle grubs, etc.  Here is a publication with more info.

 

Here is this week’s question:  What is wrong with the three cucumbers on the right?

IMG_20170523_154737158.jpg

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

Peanut Update – Start of Bloom

The following update was prepared by Clemson Peanut Specialist Dan Anco.

Some of the peanuts planted in April are starting to show their first blooms. In addition to signaling the start of the development of eventual peanut seed, bloom is also a reminder of when to apply calcium to the developing peanut crop. Large seeded runners (examples being TUFRunner 511, TUFRunner 297, and even 06G, FL-07 and 09B) and all runners grown for seed should receive 1000 to 1500 lb land plaster per acre. All Virginia types typically respond well to 1500 to 2000 lb land plaster per acre. See page 15 and 19 in the Peanut Production Guide for additional details. Foliar calcium applications are not recommended.

20170529_094809s.jpg

Photo taken May 29 from 06G that were planted April 27; 80% of that field was still at the V-4 to V-5 vegetative growth stage and was not yet blooming.

Most of the thrips damage at Blackville seems to have hit its peak and is now on the way out, with healthy new growth replacing older injured leaves. Thrips damage at our Florence test has increased a little since last week, with common insecticide treatments holding up fairly well. Most of the state can use more rain, which will help the canopies as they fill out and close the rows.

20170524_104059s

Thrips injury.

Tomato spotted wilt symptoms are just starting to show on a small number of leaves, but most TSWV infections have yet to reveal themselves. Below are two pictures showing ring-like symptoms. Seeing TSWV symptoms on peanuts lets us know if it’s there, but there isn’t much we can do once the peanuts are in the ground to further manage TSWV.

TSWVs2.jpg

TSWVs.jpg

Fungal diseases, on the other hand, routinely require management actions throughout the growing season. For peanuts planted in mid-late April, the traditional 45 DAP start of the fungicide program is coming up. For moderate to low late leaf spot disease fields, this is generally 24 fl oz/A chlorothalonil (Bravo) or 24 fl oz/A Bravo + 7.2 fl oz/A tebuconazole (Folicur). If we are planting a highly susceptible variety like TUFRunner 511 or Georgia 13M, or if this is a field with typically higher amounts of late leaf spot disease (or if rotation intervals are shorter than at least two years out of peanut), we may consider more premium fungicides at 45 DAP, such as:

16 fl oz/A Bravo + 5.5 fl oz/A Alto

16 fl oz/A Bravo + 8-10 fl oz/A Topsin

32 fl oz/A Mazinga

4.3 fl oz/A Proline.

As a reminder from the county production meetings, Mazinga has no soil disease activity (not effective against white mold). Traditionally, the latest we should start leaf spot management has been 45 DAP, and the latest we should start soil disease management has been 60 DAP. We’re looking at a few things this year to see how much evidence there might be if we need to place more emphasis on earlier management, but for now the timeframes are the familiar ones. That being said, unless we are anticipating high soil disease risk, a 45 DAP fungicide application targeting only foliar leaf spots should probably be okay. If something like Mazinga that has no soil activity would be used at a later application (60 DAP for example), it would no doubt need a mixing partner in the tank, such as 16 fl oz/A Convoy, 4 oz/A Quash, or at a minimum, 7.2 fl oz/A tebuconazole.

Check with your buying point if you are considering products with propiconazole (e.g., Tilt Bravo, Stratego, Artisan). As with last year, peanuts treated with propiconazole may not be accepted for international import into the European Union. Peanuts treated with propiconazole are still okay for the green-peanut domestic market. Overall, the industry has decreased production of propiconazole products.

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

Spring Harvest Update

We’ve had good harvesting weather this week and growers are busy taking advantage of it.  We’ve had a lot of peas, wheat, and oats harvested.  Yields have been variable so far.  ESO peas are averaging around 35-40 bushels with the highest reported yields in the high 60’s.  Wheat is ranging anywhere from the 20’s to upper 70’s.  The cold snap we got in March really hurt in some areas.  Here are some photos of the harvest.

IMG_20170530_145352506.jpg

Harvesting ESO peas in Dillon.  Around 3000 acres were planted in the Pee Dee this year.

IMG_20170530_144803589.jpg

IMG_20170530_155058175.jpg

The freeze in March hurt the ESO peas some as well.  We saw some fields that had a lot of plants burned back to the ground right before bloom.  Powdery mildew came in late in some areas and may have had some affect also.  Overall, growers are still pleased with yields.

IMG_20170531_134237961.jpg

Wheat being harvested in Dillon.

IMG_20170531_131052396.jpg

View from the cab.

IMG_20170531_130310373.jpgIMG_20170531_132524690.jpg

Some folks aren’t messing around getting their soybeans planted.  Earlier this week I saw a field with a combine on one end and a planter coming right behind it a few rows over.

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

Corn Tasseling

Some of our older fields are tasseling now and the very oldest are even starting to drop pollen.  We’re pretty much on pace with where we were this time last year.  The weather has been fair this year, so most of our corn looks pretty decent so far.

IMG_20170531_154111993.jpg

IMG_20170531_154302922.jpg

These tassels have already started to shed pollen.

The high temperature is forecast to be right around 90 for the next several days.  This should be good for pollination.  We start to see problems when we get over 95 during pollination.  Pollen production and viability decreases and silks can be late to come out, especially if its dry too.  If the temperature stays about where it is and we don’t dry out too much, pollination should be decent.

IMG_20170531_150526231.jpg

Silks ready to collect pollen.

Now is the time to really start scouting for disease.  Northern corn leaf blight (NCLB) and Southern rust are the two biggest diseases we need to look out for.  NCLB survives the winter on crop residue, so we could see it out there right now.  Fields that have had corn two years in a row are good places to find NCLB.  Southern rust typically blows up from the south and tends to be a later season disease.  Last year it came in so late that it didn’t have enough time to cause us any significant damage.  Lets hope its the same way this year.

IMG_20150609_104329_645.jpg

Northern corn leaf blight lesions.

IMG_20160802_085826496.jpg

Southern rust pustules.

If disease pressure is low, we try to hold off as long as possible before making a preventative fungicide application.  That way we only have to do it once and, ideally, it will carry us through to the end of the season.  If disease pressure gets high, that may not be an option.  Get out there and scout and be aware of whats going on in each field.  Fungicide recommendations for corn can be found here starting on page 75:  UGA Corn Pest Management

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

Cotton Marketing News – 5/30/17

FullSizeRender.jpg

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

Question of the Week: Southern Stem Blight

Last week the question was:  What is this disease growing at the base of this tomato plant?

SSB

This is a fungal disease called Southern stem blight (Sclerotium rolfsii).  This is the same pathogen that causes white mold in peanuts.  It is a soil borne fungus that survives the off season as sclerotia in the soil.  It infects tomatoes by growing on the stem right at soil line, causing the stem to decay.  Affected plants wilt and die as a result.  For more info, take a look at this page.

 

Here is this week’s question:  What are the white things on this strawberry leaf?

IMG_20170516_105429121.jpg

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

Lots of Thrips Damage in Cotton

In the last couple issues of Clemson Entomologist Jeremy Greene’s Cotton/Soybean Insect Newsletter, Dr. Greene mentions the Thrips Infestation Predictor (TIP) tool.  This tool predicts the thrips pressure of cotton based on planting date.  The chart below is from the TIP website (http://climate.ncsu.edu/cottonthripsrisk/) with Dillon, SC selected for the location.

FullSizeRender.jpg

The chart is predicting that cotton planted in early May will see the highest thrips pressure this season.  We have a lot of cotton planted in early May and from the looks of it, this chart predicted the thrips pressure accurately.  A lot of that early May planted cotton is showing thrips damage, some of it pretty severe.

IMG_20170524_150937.jpg

Cotton seedlings damaged by thrips.

Some fields could benefit from a foliar insecticide treatment, but before making any decisions to do so, take a look at the section on thrips in the SC Pest Management Handbook (pg. 109-110).  According to the handbook, the best time to make an application is before the second true leaf has unfolded.  We do have a lot of cotton that fits that description.  Once cotton reaches the four-leaf stage, there’s not much benefit to making an application.  The plants are big enough that they can tolerate some feeding pressure.

Get out there and scout and be aware of whats going on in each field.  If you’d like help scouting or to you’d like to receive Jeremy Greene’s Cotton/Soybean Insect Newsletters, please contact your local Clemson Extension agent.

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

Winter Crops Ready to Harvest

We’re in our third straight day of rainy weather now.  While its holding us up from getting in the fields, the forecast shows the weather drying up towards the end of the week.  As soon as the fields dry up some, we expect to see a lot of combines running.

IMG_20170523_145432280.jpg

Wheat field ready to harvest.

IMG_20170523_145647615.jpg

Mature wheat kernels.

There have already been a few acres of peas and oats harvested and some rapeseed desiccated.  Yield reports have varied and we expect our averages to be down across the board, considering we had Hurricane Matthew right at planting time and then a hard freeze this spring.

IMG_20150602_105831_020.jpg

Desiccated rapeseed.

Check back later for more photos and updates from the harvest.

Posted in Canola/Rapeseed, Wheat | Tagged , , , , , | Leave a comment

Peanut Update – Vigor

The following update was prepared by Clemson Peanut Specialist Dan Anco.

There have been some instances of j-rooting and poor vigor this year. Dual has a tendency to get the blame for j-rooting, but often times it is a result of poor seedling vigor. When combined with suboptimal growing conditions, seed with lower vigor have a more difficult time rising to the challenge of good growth. Drought periods the southeast experienced during the 2016 growing season set the stage for less than ideal seed production, and seed lots with lower vigor are one of its symptoms. Even seed that came from irrigated fields can be affected, particularly if excessive water loss through evapotranspiration reduced the effective amount of water that was made available to the crop.

20170509_103517s.jpg

J-rooted peanut.  Photo from Dan Anco.

What can we do? Vigor can be a little more elusive to get a feel for before planting than say something like germination. One thing we can try is to obtain the standard germination rate of each individual seed lot and compare that with the cold germination rate for that lot. If there is a wide difference between the two, then this might hint at a lower relative vigor for the lot. More work needs to be done to provide guidance and specifically determine how big of a difference becomes important, and until then this may seem a bit like a guessing game. In the absence of explicit vigor estimates of each lot, another thing we can try if planting conditions allow is to plant slightly shallower (e.g., 1.5 in versus 2 in) in years following stressful years if our seed was sourced from regions affected by drought. Planting into moisture is still more important than starting the seed closer to the surface. These are certainly compromises, and they are no substitution for healthy seed. While most peanut planting in the state is well underway, in future plantings, saving a bit a seed from each lot could be used to check germ and vigor if you have stand issues. As an added reminder, when possible seed stores best in a cool environment protected from the sun or heat for extended periods of time.

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

Cotton Marketing News – 5/11/17

2.jpg1.jpg

Posted in Cotton | Tagged , | Leave a comment