• Clean grain handling equipment (augers, combines, wagons, scoops, trucks). Kernels and fine material stuck in equipment provide a breeding ground for insects.
• Clean inside the bin and if possible, beneath the floor. Having removed a few floors, I know it’s an unpleasant task. However, under the floor plates can be several inches of fine grain dust, rodent droppings, insect parts, and fungal spores. If an annual cleaning is impractical, make a schedule and try to clean a bin every few years.
  
• Clean around the bin. Clean up grain spills and remove weeds from a ten-foot border around the bin. Spilled grain and tall vegetation provides food and shelter for both insects and rodents.
  
• Seal all cracks and crevices, entry points for insects. Cover or screen fans when not in use. Keep doors closed, and make sure they seal when shut.

Sanitation may be enough to avoid an insect infestation in Michigan bins. Much of our wheat will be stored only for a short time, heading to local mills or to the East Coast by fall. If wheat is stored for a longer period, we have the advantage of fall and winter temperatures to keep the grain mass cool, reducing insect activity. With an excellent sanitation program, well-maintained bins, and a short storage period, insecticides on wheat can be avoided altogether.

Bin sprays
If your farm has a history of insect problems in grain, or if it is difficult to clean bins and equipment, an insecticide may be useful. Bin treatments are used in and around empty structures after cleaning, but before adding grain. They kill insects still in the area and create a barrier to infestation. Treat bin floors and walls up to six feet, the foundation, and ground directly around the bin, as well as equipment. Concentrate on cracks, crevices, and other hard-to-clean areas that harbor grain dust and insects. The following is a list of products registered as bin treatments. Read the product label carefully before using any of these insecticides, as formulations can vary and labels may change from year to year. Some products are registered only for bins containing certain grains.

• Tempo (cyfluthrin - a pyrethroid). Registered for all indoor warehouses, bins, grain-handling equipment, trucks, rail cars and areas around bins. Tempo is not registered for direct application to grain itself.
  
• Storcide II (chlorpyrifos-methyl + deltamethrin): This product replaced Storcide and Reldan.
  
• Malathion - numerous formulations (an older OP). Registered for use in structures that will contain barley, corn, oats, rye and sorghum. Do not use in bins that will contain soybeans. Refer to individual product labels, as some may not be registered for use on stored grain and others are being phased out.
  
• Diatomaceous earth. Many products are available, such as Insecto, Protect-It, and PermaGuard. DE is a chemically inert dust that abrades the insect cuticle, or outer skeleton, causing the insect to lose water, dry out and die.
  

If you follow these recommendations, you will likely not need to use an insecticide on the grain itself or during storage in Michigan. Compared to southern states, we can cool grain faster after harvest, reducing insect and fungal activity.

Treatments directly to grain
If you anticipate storing the wheat for a long period, you may decide to apply insecticide to the grain itself. There are two different types of insecticide applications on wheat. If the bin and the wheat entering the bin is clean, and it is not layered over old grain, a “top dress” or surface treatment may be all that is needed. A surface or barrier treatment is applied on the last grain going into the bin or directly on the grain surface once the grain is in the bin. A surface treatment must not be disturbed after application, since this ruins the barrier. Surface treatments protect against insects entering from the top of the bin; for example, Indianmeal moth, but will not control insects already present lower down in the grain mass (for example, if you put new grain over infested old grain).

Protectants are insecticides directly applied to the grain stream as it enters the bin. These treatments are designed to control infestations throughout the entire bin. In Michigan, protectants are generally not necessary if grain will be used or sold within six months, and if the bin is properly cleaned, sealed, and sprayed with a sanitary spray (see above) prior to fill.

Products labeled as protectants and/or surface treatments for wheat include:

• Storcide II (chlorpyrifos methyl + deltamethrin). For use on barley, oats, and wheat.
  
• Malathion. Again, many trade names and formulations, registered for different sites and uses. Refer to individual product labels, as some may not be registered for use on stored grain, and others are being phased out. Be aware that grain that has been treated with malathion may not be acceptable to some millers.
  
• Diatomaceous earth. Registered for barley, corn, oats, rye, soybean, sorghum, sunflower, wheat. Note that different formulations are registered for different crops, therefore check the labels. Diatomaceous earth is abrasive and may cause equipment wear. Newer formulations of Diatomaceous earth require a lower application rate, and may be easier to use than older formulations.
  
• Pyrethrins. Sold under several trade names. Registered as a surface treatment for barley, corn, oats, sorghum, sunflower, and wheat. It is not registered for soybean.
  
• Diacon (methoprene). Registered as a surface treatment for barley, corn, oats, sorghum, and wheat, it is not registered for soybean. Methoprene is an insect growth regulator which disrupts insect development. It thus controls larvae, but not adult insects.
  
• Dipel, Top-Side, etc. (Bt). Registered as a surface treatment for barley, corn, oats, rye, sorghum, soybeans, sunflowers and wheat. Bt kills Indianmeal moth larvae. Some formulations are acceptable on organic wheat. Bt will not control adult moths, weevils and grain beetles.
  

Additional insecticide notes: Actellic (pirimiphos-methyl), which can be used as a protectant on corn, is not labeled for wheat. Sales of Reldan, which was available as a bin spray and protectant, ended December 2005. Existing stocks should be gone. Grain treated with Reldan has until 2009-10 to move through channels of trade. 

As the wheat season is winding down, I thought I’d share a few last disease-related findings as we approach harvest. It seems that Michigan has escaped an epidemic of head scab again this year, and the Penn State Model accurately predicted (mostly low) risk levels. Most areas of the state have reported relatively low occurrence of symptoms in the field. Hopefully, this will translate into low to no levels of DON (vomitoxin) in harvested grain, although visible symptoms aren’t always a clear indicator of levels of DON at harvest.

Leaf rust occurred late in the season, at levels high enough to likely affect yield in susceptible varieties. Stem rust has been found at very low levels on some wheat in the Tuscola area variety trials plots near Richville (see photo). Purpling of stems and purple blotches on glumes have appeared on the variety Hopewell in many parts of the state and on a few other varieties to a lesser extent, but is very noticeable on Hopewell. The condition, called melanism, can be confused with stagonospora glume blotch. There is some glume blotch around, making it confusing to distinguish between the two. Pycnidia (tiny, pimple-like fruiting bodies containing spores) can often be found embedded in the lesions on the glumes caused by Stagonospora. You may also find superficial black sooty mold on the glumes that can be easily wiped away from the surface. Melanism shows up as superficial purple to brown patches of pigment on the glumes, and does not create lesions. Melanism can be caused by a variety of environmental stresses, such as high humidity, excess rain, or high levels of UV radiation. The stresses cause increased production of a pigment called anthocyanin. It does not affect yield.

Stem rust on wheat in the Tuscola area.

On Wednesday, July 2, near Charlotte, Michigan, located in the central part of the state, there was a terrible hail storm that devastated soybean and corn fields. These pictures show a field of plants with no foliage on them. Throughout my 28 years with MSU Extension, I have never seen damage this severe from hail. At the MSU W. K. Kellogg Biological Station we were hit by hail, however, nothing in comparison to these fields near Charlotte.

Growing degree day base 50 totals for areas around the southwest include from May 1

Our average heat accumulation is around 23 base 50 GDD’s per day at this point in the season. There is a fair amount of variability in heat accumulation levels across the region depending upon any given location’s proximity to Lake Michigan. In general, inland areas are about 1.5 days ahead of the 30 year average base 50 GDD accumulation levels.  

Crop report
Commercial corn continues to look good. The earliest planted fields are approaching Vt (tassel emergence), with lots of fields about 1.0 to 1.5 weeks behind that mark. The plants have grown very well with abundant sunshine, ample thunderstorm rainfall and cooler evening temperatures. Stands look much better this year compared to last in terms of Asiatic garden beetle white grub feeding, but there are still some areas of stand loss and un-evenness in a few rotated fields. I have not seen western corn rootworm beetles yet, but Japanese beetles and Asiatic garden beetles have been emerging for about two weeks now. Sporadic hail clipped corn fields across the region during various stages of growth over the last two weeks. With the exception of the Charlotte area, most damage has been very localized and should be fairly well tolerated by the crop. Areas that have been subjected to repeated flooding rainfall show washouts, drown outs and areas of poor growth where the water has stood in fields for any length of time.

 As we have moved beyond the nitrogen sidedress window on commercial corn fields, there may be some concerns about adequate remaining nitrogen following potential losses by leaching and de-nitrification on fields where nitrogen was applied early in the season.

The story in the seed corn industry continues to spread out crop maturity based on planting date. The early planted fields are approaching de-tasseling either over the weekend or early next week. We also have some fields that are just getting big enough for sidedress nitrogen applications to go on. Fungicide applications for the control of leaf rust and other leaf diseases have begun. As we approach silking, producers should monitor the activity of silk clipping insects like Japanese beetles and western corn rootworm beetles, which are likely to emerge soon. 

The early planted soybeans are at R1 to early R2, and they have been growing very well in sandy soils. As you move to areas where heavier soils pre-dominate or where flooding has happened quite regularly this spring, the stands become much more uneven in growth and appearance. Some high organic matter soils have exhibited manganese deficiency symptoms. Most post emergence herbicide applications have been made, and the weed control appears to be working well in most situations. You can see pokeweed in many fields, along with volunteer corn, but most other weeds have been controlled. Japanese beetles have begun to feed in soybeans, so leaf de-foliation will be on the increase. Soybean aphid numbers remain non-existent or very low in fields I have checked. Soybean leaf diseases are also very low at this time. There are some signs of septoria (brown spot) on the lower leaf tissues, particularly more evident where conditions were drier early last week. We may be more at risk for white mold in soybeans this year with the wet conditions that have been seen at early flowering. We can begin to see evidence of soybean cyst nematodes in areas where their populations have been historically very high, but the resistant varieties have allowed most of the areas of these fields to be quite productive.

Those alfalfa producers that were able to harvest their first cutting early have been seeing the best opportunities to harvest high quality hay this season. Despite the short windows of opportunity, producers were able to get a good chunk of the second cutting harvested, and the quality was very good from what I have seen. Many producers were probably moving hay out of the fields when storms began on July 2. Potato leafhopper numbers are greatly on the increase in the southwest, so be prepared to treat re-growth alfalfa to protect the small plants. Fields in Van Buren and Cass counties, where cutting was about to begin, were showing signs of hopper burn late last week.

The wheat crop is rapidly approaching harvest. Lodging from the heavy storms varies greatly upon location, and the severity of the winds, rain and hail in those areas.

There will be some reduction in overall yields due to head scab, but yield levels still look pretty good in the southwest region. Producers in St. Joseph County are trying to get wheat harvested as early as possible to allow for planting of second crop snap beans and pickling cucumbers.  

Oats are beginning to turn. Yield potential continues to look good.

Hail tattered corn near Charlotte, MI.	Soybean plants defoliated by hail.

Storm thrashed wheat.	Wheat lodged from storm.

Clouds start filling the skies of Michigan as shortwave troughs, a cut off low in Canada and a large trough beginning to move into the area starting tomorrow. Early Friday morning (July 11) should be fairly active in the Lower Peninsula with some estimates of over an inch of precipitation. Lower amounts of precipitation will occur across the state on Friday moving into Saturday, with a larger trough coming through the region on Saturday afternoon. The system will quickly move out and make way for sunny conditions beginning early next week.

Temperatures Thursday should range from the upper 60s in the north to the lower 80s in the south. Friday and Saturday are both similar temperature wise with highs in the upper 70s to upper 80s. The passage of the trough will cool things down though, with highs on Sunday ranging from the mid-60s to near 80°F. Monday sees things warming up again across the state as the sun comes out with highs in the upper 60s to low 80s. This temperature range seems to hold steady until the middle of next week.

The National Weather Service 6‑10 day outlook covering July 15 through July 19 calls for normal temperatures and precipitation across the state, eastern parts of the Upper Peninsula look to be above normal for temperature and rainfall. The outlook for the 8-14 day period (July 17 – July 23) calls for above normal temperatures and above normal precipitation. The long term outlook shows that conditions for the rest of the month should be near normal, with a gradual shift back to a more seasonable range in conditions.