Wednesday, August 24, 2016

Start Managing for Fusarium Head Blight Now Before You Plant the 2016/17 Crop

By Shawn P. Conley and Damon Smith

Most WI winter wheat growers dodged the Fusarium head blight (FHB or scab) bullet in 2016; though many farmers especially those in SW WI became so disgusted with dockage and rejections in both 2014 and 2015 they didn't plant a single acre this year. Therefore as we prepare to put the 2017 wheat crop into the ground here are a few considerations for managing FHB before we drop a single seed.

1.      Crop rotation matters. Data from our long-term rotation studies indicate that wheat following soybean provides the greatest yields. The next best options are wheat following corn silage (6.5% less) then corn for grain (21% less). Wheat following alfalfa or another leguminous crop are also good options, though the N credits following alfalfa may best be served going to corn. Furthermore, background fungal pressure (residue on and in soil) from the FHB fungus will be greater following corn then soybean or another legume, however know that spores that infect your wheat crop can arrive from  outside the field. Please click to see more information on the Top 8 Recommendations for Winter Wheat Establishment in 2016.  
2.      Variety selection matters. Data from our 2015 and 2016 WI Winter Wheat Performance Test shows variable yield and disease performance among the varieties listed. Select those varieties that have both good to excellent FHB (2015) and Stripe Rust (2016) resistance and high yield. When evaluating disease resistance, low numbers for both incidence and severity can be helpful, but the major focus should be placed on  incidence (measure of the number of symptomatic plants in a stand).
3.      Application timing matters. One of the biggest challenges year in and year out is improper fungicide application timing. Our data suggests that on susceptible (Hopewell) or moderately susceptible varieties (Kaskaskia) equal efficacy of the fungicide Prosaro at a rate of 6.5 fl oz/acre can be achieved when applied between Feekes 10.5.1 (anthesis) and 5 days after anthesis. Given the variability of head emergence and anthesis across a landscape it may prove best to wait a few days until the whole field is flowering than to apply too soon.  If the extruded anthers have turned from yellow to white across the whole field then you are likely too late. Remember it roughly takes a wheat head 7 days to completely self-pollinate.
Fusarium head blight incidence ratings for four soft red winter wheat varieties treated with Prosaro SC fungicide at 6.5 fl oz/a at anthesis (Feekes 10.5.1), five days after anthesis, or not treated in Wisconsin in 2015.
Hopewell (Susceptible)
Kaskaskia (Moderately Susceptible)
Pro 200
(Moderately Resistant)
Sunburst (Moderately Resistant)
Prosaro SC @ 6.5 fl oz/a (Feekes 10.5.1)
9.5b
2b
0.5
4
Prosaro SC @ 6.5 fl oz/a (5 days after Feekes 10.5.1)
7.5b
5.25b
2.75
2.75
Non-treated control
31.25a
17.5a
3
1.5
Pr>F
0.01
0.01
ns
ns
LSD
6.44
6.44
ns
ns
4.      Choose the right fungicide class. Make sure you use the appropriate fungicide product and class to manage FHB. The label for products containing strobilurin active ingredients (FRAC group 11) ends prior to flowering. Late application can actually lead to increased mycotoxin levels. Triazole containing products (FRAC group 3) are recommended for FHB control. For a list of products and efficacy ratings, visit the Field Crops Fungicide Information Page
5.      Harvest timing and flash drying. The word on the street is that if FHB appears to be a problem in 2017 elevators will push growers to harvest early (18% moisture or higher) and subsequently dry grain to mitigate mycotoxin levels. While drying grain to 13% or less moisture is a good storage practice, know this process may kill the pathogen but any mycotoxin levels already in the grain will not dissipate. Vomitoxin is a very stable molecule and IS NOT degraded by heat, freezing, or drying.    

Tuesday, July 12, 2016

Small Grains Harvest and Combine Fires

From John Shutske:Professor & Extension Specialist; Biological Systems Engineering

It looks like wheat harvest is rolling in parts of the state.   I saw a post from a friend in New Glarus saying they’d started late yesterday. Just a quick reminder on combine fire prevention and protection --  “Protection,” because SOME machines will burn regardless of how hard you work at it.  So you need to know what to do to minimize the damage.  Over the years I (or my former students) have done a bunch of investigative work on about 12,000 fires (combines, tractors and other specialty harvesters).  We’ve learned a lot….

See:


Here are some specific reminders:

  1.  Keep the engine compartment as clean and clear of debris as possible.  Caked/oily residue means there’s a leak someplace.  Fix it. 
  2. Listen closely for unusual noises and pay attention to warning lights and sensors that could indicate bearing/belt/and other drive component issues.  Fix them. 
  3. Many combine fires are ignited by the electrical system – blown fuses, flickering lighting, etc. are all signs that you might have damage.  
  4. The ABC dry chemical fire extinguisher is probably still the most cost-effective and overall effective type of extinguisher.  The bigger the better (at least 10 pounds).  Mount extinguishers (recommend at least two ten-pounders) where they can be grabbed quickly in the cab AND/OR from the ground.  
  5. If a combine does catch fire, pull it away from any standing crop quickly.  Shut off the engine.  The longer the fire burns, the more difficult it will be to put it out.  If the engine is left running, it will be almost impossible to extinguish (even if the fire department shows up)! 
  6. Grab your extinguisher if time allows and get out.  Call for help.  It is not always possible to put out a vehicle fire with a handheld extinguisher.  A second one is often needed, even on a smaller fire. 
  7. Always consider PERSONAL safety.  A combine fire that gets into a fuel, oil, or other flammable liquid system will burn hot.  Even more so if a tire is involved.   A machine can be replaced.  A life cannot. 
  8. If you’ve used an extinguisher (even for a short burst), it MUST be recharged.  If you’re not sure where to recharge and re-tag your extinguisher, call your fire department.
 

Small Grains Harvest and Combine Fires

From John Shutske:Professor & Extension Specialist; Biological Systems Engineering

It looks like wheat harvest is rolling in parts of the state.   I saw a post from a friend in New Glarus saying they’d started late yesterday. Just a quick reminder on combine fire prevention and protection --  “Protection,” because SOME machines will burn regardless of how hard you work at it.  So you need to know what to do to minimize the damage.  Over the years I (or my former students) have done a bunch of investigative work on about 12,000 fires (combines, tractors and other specialty harvesters).  We’ve learned a lot….

See:


Here are some specific reminders:

  1.  Keep the engine compartment as clean and clear of debris as possible.  Caked/oily residue means there’s a leak someplace.  Fix it. 
  2. Listen closely for unusual noises and pay attention to warning lights and sensors that could indicate bearing/belt/and other drive component issues.  Fix them. 
  3. Many combine fires are ignited by the electrical system – blown fuses, flickering lighting, etc. are all signs that you might have damage.  
  4. The ABC dry chemical fire extinguisher is probably still the most cost-effective and overall effective type of extinguisher.  The bigger the better (at least 10 pounds).  Mount extinguishers (recommend at least two ten-pounders) where they can be grabbed quickly in the cab AND/OR from the ground.  
  5. If a combine does catch fire, pull it away from any standing crop quickly.  Shut off the engine.  The longer the fire burns, the more difficult it will be to put it out.  If the engine is left running, it will be almost impossible to extinguish (even if the fire department shows up)! 
  6. Grab your extinguisher if time allows and get out.  Call for help.  It is not always possible to put out a vehicle fire with a handheld extinguisher.  A second one is often needed, even on a smaller fire. 
  7. Always consider PERSONAL safety.  A combine fire that gets into a fuel, oil, or other flammable liquid system will burn hot.  Even more so if a tire is involved.   A machine can be replaced.  A life cannot. 
  8. If you’ve used an extinguisher (even for a short burst), it MUST be recharged.  If you’re not sure where to recharge and re-tag your extinguisher, call your fire department.
 

Monday, May 16, 2016

Some Risk for Wheat Crop Injury From Saturday's Cold Temps


Saturday mornings cold temperature may lead to crop injury in low lying areas across Southern WI. Based on the development in our wheat plots the highest risk for yield loss would likely come in the southern tier of WI counties. The wheat at our southern locations are either at the Feekes 8 (flag leaf visible) or 9 (flag leaf ligule and collar visible) crop growth stage dependent upon variety. 
 
Image 1. Feekes 9 crop growth stage at Arlington WI on 5/16/16.
Crop injury at these growth stages would occur in the 24 to 28 (duration of up to two hours) degree F temperature range. We did not see this temperature extreme at our Arlington location (Image 2; low temp of 30.5) however I have heard reports of extended cold temperatures in the sub 28 degree F range.   
Image 2. Arlington WI weather data for the last week.

The two types of crop injury I would be concerned about include stem damage and spikelet (head) injury. In Image 3 below you can see the brown discoloration and water soaking to wheat stems caused by freeze injury. This  injury eventually lead to severe lodging among select varieties (Image 4). If you see this type of injury it would be best to take this field as a forage crop ASAP. 

Image 3. Freeze damage to wheat stem.

Image 4. Subtle difference is crop growth stage led to severe lodging due to freeze injury.
The other type of injury would be direct damage to the wheat head. Peel back the boot and expose the wheat head. If healthy individual florets on the spikelet will appear pale green (Image 5). If they begin to appear water-soaked or off colored (brown) then crop injury occurred).  

Image 5. Healthy spikelet and florets.
For more detailed information I have attached a link to a publication entitled Spring Freeze Injury to Kansas Wheat.  For ease I have also removed a table from that publication to stress the importance of growth stage on damage potential  (Table 1).

Table 1.  Wheat Resistance to Freeze Injury (From: Spring Freeze Injury to Kansas Wheat)