Green Plants and Brown Pods?

The picture below was take by Dr. Mike Weiss, showing a curious condition we are seeing in some areas.   It has been brought about by the weather conditions we have seen this season.  It is best to be aware of it and plan your harvest schedule accordingly.    I also attached an article from Purdue giving some additional information.    Please have a safe and productive harvest!   Let us know if we can yield check any of your fields.

rob 10-10-13

 

Green stem syndrome present in some Indiana soybean fields

?????????????????By Amanda Gee | Posted on 9/30/2013

WEST LAFAYETTE, Ind. – Some Indiana soybean fields are showing symptoms of green stem syndrome, a Purdue Extension soybean specialist says.

Green stem syndrome occurs when soybean pods and seeds mature – turning harvest color and drying out – while the stems remain green. Late-season stresses that interrupt seed-fill, such as weather, the environment, viral diseases or insect infestations, usually cause the problem.

“It’s been noticed around the state, spots here and there where later-in-the-season weather stressed the plants,” Shaun Casteel said. “The dry weather and heat caused plants to abort pods. The plants’ demand for pod development and seed fill wasn’t there anymore, so the plants started maintaining the stem as the plant matured.”

Casteel said farmers should go into fields that seem to be browning and see if both the pods and stems are maturing.

“This year with some of those green stem-type fields, producers need to take a look at the pods themselves and the grain to see if they are dry enough for harvest,” he said.

Soybeans should be harvested at or slightly above 13 percent moisture to maximize yield, but green stems are tough to harvest.

Casteel said producers with fields exhibiting green stem syndrome have two options.

The first is to harvest the beans at optimal grain moisture to capture water weight. Doing so likely will slow harvest and increase fuel costs because of the green stems.

“For harvest, be prepared to have to ‘chew’ through fields with green-stem syndrome with the combine, especially with older equipment,” Casteel said.

Another option is to wait and harvest the plants when the stems turn brown. This option is easier on equipment but likely will reduce yield due to lost water weight. Delaying harvest for a few weeks also could allow the pods more time to dry out and possibly shatter.

“Producers need to be aware that this phenomenon is occurring so they can make informed decisions about optimizing harvest and reducing losses in yield and profit,” Casteel said.

Source: http://www.purdue.edu/newsroom/releases/2013/Q4/green-stem-syndrome-present-in-some-indiana-soybean-fields.html

— Rob Shields, Agronomist

Stink bugs damaging my corn?

According to the following article from Ohio State, we can see injury in corn. See the pictures they provided in the article below so you can see what the damage looks like. The authors also mention that sweet corn is more prone to stink bug damage. Read the article below for further information and let us know if you think you spot some in one of your fields.

Corn Ears Showing Stink Bug Injury

Andy Michel, Ron Hammond, Celeste Welty, Peter Thomison, Ohio State University  |   September 23, 2013
Stink bugs on corn.

Stink bugs on corn.

Stink bug damage in soybeans is well documented in Ohio. However farmers may be surprised to learn that stink bug injury can also be seen in corn. Usually the damage in field corn is localized to “scarring on kernels” or causing a “mottled” appearance near the tip of the ear but severe injury has been observed (see photo). Sweet corn is particularly susceptible to stink bugs, with similar damage symptoms.’

Stink bug damage on corn.

Stink bug damage on corn.

Last week we saw stink bug injury at the Northwest Branch near Hoytville and the Waterman Farm in Columbus. At Waterman, the damage was associated with brown marmorated stink bugs, but green stink bugs were more common at NW Branch. Damage was evident on husks where stink bugs appeared to be feeding (see photo). In the southern states, stink bugs cause significant losses in field corn. When stink bugs pierce through the husk and feed on the ear during early development, the cob will not develop on that side, but continue growing on the back side giving the ear a characteristic banana shaped appearance.

The shuck will also stop developing, exposing the grain to bird and insect damage. Injury also includes shrunken and/or missing kernels. Heavy stink bug populations can reduce not only yields but also the quality of the grain. While we have not seen any economic losses from stink bugs in field corn, growers should be aware of their presence and the damage they can cause.

Source: http://corn.osu.edu/newsletters/2013/2013-31/corn-ears-showing-stink-bug-injury.

– Rob Shields, Agronomist

– Rob Shields, Agronomist

A new soybean disease enters Wisconsin: Soybean Vein Necrosis Disease (SVND)

Soybean Vein Necrosis Disease

Soybean Vein Necrosis Disease (source: http://agdev.anr.udel.edu/weeklycropupdate/?p=3762)

Soybean diseases are always hard to diagnose. I use the color picture guides as a reference but if I cannot positively identify them I usually send down a sample to the UW Plant Disease Diagnostic clinic for a positive identification. Remember a virus, like the soybean vein necrosis virus, cannot be controlled with a fungicide. The best way to prevent a soybean virus is to keep the thrips away from your crop. Thrips infect the soybean plants when they feed upon them, similar to how mosquitoes transmit the west Nile virus. No matter what disease you suspect you may encounter out in your soybean fields, the best defense is a having a strong, well-fed plant with as few stressors acting upon it as possible.

I found the following article by Damon Smith (Extension Field Crops Pathologist, Department of Plant Pathology, University of Wisconsin-Madison) in the recent edition of the Wisconsin Crop Manager to be very insightful.

In 2012 soybean vein necrosis disease (SVND) was described for the first time in Wisconsin. This is a relatively new disease of soybean, which is caused by Soybean vein necrosis virus (SVNV). SVNV was first described in 2008 in the Mid-south soybean production region. Since then, SVND has been found in much of the major soybean production region of the U.S. including the North Central region.

SVNV is a Tospovirus similar to Tomato spotted wilt virus. It is the first Tospovirus known to infect soybean. Tospoviruses are known to be very destructive on other plant crops, therefore, there is a lot of interest in determining the importance of SVNV in soybean production systems. Very little is actually understood about the epidemiology and also the management of SVND. Researchers around the country are working on various aspects of the system and several state and regional soybean commodity boards have funded research on SVND.

Recently Zhou and Tzanetakis (2013) described some of the first studies on the epidemiology of SVNV. Their findings suggest that SVNV is like other Tospoviruses in that it is primarily transmitted by thrips vectors. Soybean thrips are a commonly occurring insect in the Mid-south and were used in their studies to demonstrate that the virus can be transmitted via thrips vectors. In Wisconsin, soybean thrips are not as common. However, other species of thrips can be found in soybean fields depending on the time of the season. Through funding granted by the Wisconsin Soybean Marketing board, our laboratory is currently monitoring thrips populations in soybean fields around the state. We are evaluating thrips species and populations over time through trapping methods. We are also surveying these fields for SVND severity and documenting any variety resistance in soybean cultivars commonly grown in Wisconsin. Finally, we have separate trials were we are evaluating yield loss due to SVNV. Our research will complement research in other states and the results will be used to develop and disseminate management recommendations for SVND in the North Central Region over the next several years.

(Source: http://ipcm.wisc.edu/blog/2013/09/soybean-vein-necrosis-disease-in-wisconsin-with-video/)

– Rob Shields, Agronomist

Pockets of soybean aphids found…

Soybean aphids found north of Galesville today.

Soybean aphids found north of Galesville today.

We were out scouting some soybean fields north of Galesville today and found some pockets of aphid pressure. Please remember to be checking your fields on a regular basis.

On a related note, here is a pop quiz for the day: Is the insect pictured below a friend or foe?

Lady beetle Larvae

Click to enlarge photo.

The answer? Friend! This little guy is actually the larval stage of the lady beetle. The lady beetle eats soybean aphids. Remember with the insects the stages are egg, larvae, pupa, and adult.

– Rob Shields, Agronomist

Insect activity found today…

Near Galesville today I found my first Western Bean Cutworm Egg Mass. The moth counts are very low this year. We put out 5 pheromone traps and have found very few this season. I also found a fair number of Corn Rootworm beetles feeding on the fresh silks today. Please keep a watchful eye on your corn fields during the critical pollination phase. The published threshold is “when silk clipping is occurring on 25% or more of the plants during pollen shed.” Also, if this field will be corn next year, it is best to plan your management strategy to combat this pest now due to the fact that they will be laying eggs now to attack next year’s corn crop. Please let us know if you have questions on any of these issues. Thank you.

– Rob Shields, Agronomist

Western bean cutworm egg masses.

Western bean cutworm egg masses.

Corn rootworm beetle feeding.

Corn rootworm beetle feeding.

Corn rootworm beetle feeding.

Corn rootworm beetle feeding.

Crop Update

Corn

Our black light traps are showing low to very low levels of western bean cutworm moths, European corn borer, and corn earworm, especially compared to the levels we were finding this time last year. We have found a few corn leaf aphids on some of the heavier ground in our area so be sure to be monitoring your fields for this pest as the summer progresses. Much of the corn in our area is at the tail end of pollination and is looking good. Low levels of rust can be found in most all of the fields in our area. Anthracnose leaf spot is common in fields that are corn after corn. We have only found a few fields with trace amounts of Northern corn leaf blight to date, but with wet weather on the forecast it is likely to spread.

Soybean

Japanese beetle, green clover worm, aphids have been the main insects we have been finding these past few weeks, but no fields have reached economic thresholds yet. Be vigilant in scouting for aphids as the extended forecast of cool weather will be very conducive to aphid reproduction. University thresholds are 250 aphids pre-plant which may sound like a lot, but when the population can double every few days it does not take very long for a field to become infected. Septoria brown spot is slowly building in the lower canopy of many of the soybean fields in our area. Consider a foliar fungicide if you have moderate or heavy disease pressure at this time. The key time for fungicide on soybeans is the R1 (beginning flower) to R3 (beginning pod) stage. Many of our fields are in the R3 stage to R4 (full pod).

Potato

Late blight continues to be a problem and is slowly but surely spreading with each week, bringing one or two more fields found to have been infected. So continue to apply fungicide on your scheduled interval being sure to add premium late blight material especially on the weeks of cool wet weather like we have been having. We are currently in the midst of second generation Colorado potato beetles with adults already laying eggs and larvae hatching. Some of the petiole numbers are starting to crash as the crop begins to pour energy into the tubers. We have been checking tubers for shape and size last week and this week to see if an MH30 application is needed to correct the shape of the tubers.

– Otto Oemig, Agronomist

Soybean aphids are showing up in certain areas…

Soybeans aphids from today, July 30.

Soybeans aphids from today, July 30. Click to enlarge.

Soybean Aphids found in Waushara county today. Please check your soybean fields every 3 to 5 days to make sure you don’t have a population that is building. Let us know if you need any help looking for this pest.

– Rob Shields, Agronomist

Armyworms ATTACK area corn fields

Please keep a close eye on your corn fields, especially those with a lot of trash or weeds. These photos taken by Wayne Roemer, an Agronomist out of our Plover location, show the extreme damage they cause. Wayne took these photos 8 miles south of Waupaca. Sally Turpin, an Agronomist out of our Mauston location, also found a heavily damaged field just north of Mauston. This pest moves rapidly and can leave only the stalk and mid rib on the corn plant. It is important to spray before the damage gets this bad. Please let us know if you need any help checking your fields.

– Rob Shields, Agronomist

Armyworms in Waushara county.

Armyworms in Waushara county.

Armyworms in Waushara county.

Armyworms in Waushara county.

Armyworm damage north of Mauston.

Armyworm damage north of Mauston.

 

Japanese Beetles Attack!

A lot of our field and vegetable crops are now being attacked by Japanese Beetles, see photos. They consume the leaves of many crops, such as corn, soybeans, snap beans, tomatoes, melons, etc. Please check your fields now or contact one of our Allied Cooperative agronomists to assist you.

 – Rob Shields, Agronomist

Japanese beetle 1

Soybean Aphid Alert!

Soybean aphid (photo courtesy of Wikimedia)

Attention! Soybean Aphid Alert! Soybean aphids have started to hit our area. We found out some fields are at threshold. I just visited with a grower whose fields are in Southern Adams county and Northern Columbia county and he has soybeans fields that need to get sprayed. Be sure to use a minimum of 15 gallons of water and a lot of pressure to get good coverage. I have had very good results using Leverage 360 insecticide in the past at the 2.8 oz rate. If you are spraying the field consider tank mixing in a foliar micronutrient package, such as Max in ZMB, and/or a foliar fungicide such as Stratego YLD at 4 oz. Please contact one of our agronomists to find the best recipe for your acres. Thanks and be safe out there!

– Rob Shields, Agronomist

UPDATE (5:36pm): In talking with our team up in Galesville this afternoon it sounds like the Soybean aphids are very bad up on the Trempealeau Prairie, just west and a little north of our Galesville location. They are ordering in more Leverage to combat this pest. Please check your fields on a regular basis. Typically the threshold is at 250 aphids per plant.