A couple of week's ago I was in the kitchen pouring my first cup of coffee for the day, when I happened to notice a relatively large and unfamiliar bug crawling across the floor. Being a good "crop scout," I walked over to catch the creature, all the while giving thanks that I was the one who made the discovery, and not my poor wife. Imagine my surprise when I leaned over to capture what I assumed was a lost and confused masked chafer or possibly a small June beetle, only to find myself staring at a brown marmorated stink bug!

So what's the big deal, and why am I writing about this particular insect in a blog about crop production and applied crop research in southern Illinois?? After all, we've been dealing with stink bugs for years in crop production, even though one seldom if ever finds one inside the house. The brown marmorated stink bug isn't the common brown stink bug, or green stink bug you often find in the fields or in the garden. A native of Korea and Taiwan, this pest was first found in this country in Allentown, Pennsylvania back in 1998. In just 15 years it has gone from being a new discovery, to being present in 40 states. It has become a major pest of agricultural and horticultural crops, as well as a nuisance house pest in several eastern states.

The earliest reported findings of this insect in Illinois were just a year or so ago in the northeastern metropolitan corner of the state. I found one this spring on my kitchen floor in southwestern Illinois. Was it already here last fall and overwintered inside the walls of my house? Did it hitchhike south on a truck coming from Chicago this spring? Was it alone and lonely, or part of a larger breeding population that is becoming established in the region? I don't know the answer to these questions, but I strongly suspect that the answer will become obvious sooner rather than later. What will really make this insect noticed by the public is that it "aggregates," that is, it collects in large numbers to feed (like Japanese beetles), and to overwinter inside of houses (like the multi-colored Asian lady beetle). If it becomes established in our region, it has the potential to have a major impact on corn, soybean, fruit, and vegetable production.

Fortunately, there are numerous online resources to help you to identify this pest, differentiate it from other stinkbugs, and hopefully manage it if (more likely "when") it becomes a major problem in our area. As a starting point, check out the following links:

Stop Brown Marmorated Stinkbug.org http://www.stopbmsb.org/

Penn State Extension http://ento.psu.edu/extension/factsheets/brown-marmorated-stink-bug

Rutgers University http://njaes.rutgers.edu/stinkbug/

Following up on yesterday's blog entry, Dr. Carl Bradley has written another Bulletin article on Fusarium head blight (FHB) of wheat. FHB, also commonly referred to as "scab" is the most serious wheat disease that we potentially deal with each year. Not only can it seriously reduce yield and test weight, grain quality can be reduced because the causal fungus also has the ability to produce the mycotoxin deoxynivalenol (DON).

FHB is most apt to develop when prolonged wet, humid conditions occur just before, during, and immediately after flowering in wheat. There are several fungicides (Caramba, Prosaro, Proline, and tebuconazole) that are effective at reducing disease severity, but they have a very narrow application window (Feekes Growth Stage 10.5.1, or early flowering) and proper application timing is critical. With proper fungicide selection and application timing, FHB severity can be reduced by 60 - 70 percent. However, this level of control will drop by almost half if the application timing is off by just 5 days too early or too late. Fungicides work best when applied to wheat varieties that also have a higher level of genetic resistance to Fusarium head blight.

Depending upon where you are located in the southern third of the state, wheat development ranges from Feekes Growth Stage 9 (flag leaf fully emerged), to approaching Feekes Growth Stage 10.5 (heading complete, but not flowering). This is a critical time period for wheat development, and fields should be carefully scouted to monitor for fungal leaf and head diseases. On May 3, Dr. Carl Bradley wrote and excellent Bulletin article on scouting and management of wheat foliar diseases.

Be careful not to confuse disease symptoms caused by viruses with disease symptoms caused by fungal pathogens. While there are numerous fungicides that that help effectively manage fungal diseases, these fungicides provide absolutely no control of virus diseases.

Volunteers in Illinois and Iowa are montoring crop insect pest potential through the use of pheromone traps placed in numerous counties throughout both states. Growers and consultants can see the resulting trap capture numbers by going to a web site maintained by Iowa State University at the URL http://apps.csi.iastate.edu/pipe/ . Click on the link "view all maps" to see the list of pests and sites that is currently available.

Currently, black cutworm moths are the only pest being trapped, but as the season progresses we will be adding traps for true armyworm, corn earworm, European corn borer, western bean cutworm, and fall armyworm.

We are now less than a week away from May 1, and the state has less than one percent of its corn planting completed. Perhaps that is a good thing under the circumstances, because that "one percent" continues to struggle to emerge from cold, saturated soils. An excellent article by Dr. Emerson Nafziger in The Bulletin discusses research on corn planting dates, and then compares that data to what has resulted from actual corn planting progress throughout the state over time. Bottom line: Don't panic yet and force planting into fields that aren't ready.

While no one is likely to argue with the fact that timely corn planting (mid-April through the first week of May) is better than late planting, forcing planting into fields that are still overly wet can be a recipe for disaster, especially if the summer later turns out to be hot and dry. Tracked-tractors, 4-wheel drive tractors and large vertical tillage tools provide a temptation to "open up a field" in order for it to dry out faster and get it planted. What results is a shallow "dry" seedbed on top of a still saturated, compacted topsoil and subsoil. Several bad things can happen from this situation. Working soils under wet conditions will increase compaction, decrease soil pore size, and ultimately affect root penetration later on as soils eventually do dry out. Soil drying below the tillage zone will actually be slower than if no tillage had been done, because the shallow surface tillage breaks up the macropores and root channels from the subsoil to the surface, and creates a mulch layer on the soil surface. If the soil area immediately below where the seed is germinating remains saturated for an extended period, then roots will not penetrate downward. Areas of poor root penetration can be later seen as slower growing plants that become the first to exhibit signs of leaf rolling and moisture stress during the heat of the summer as the soil surface becomes abnormally dry.

Southern Illinois also experienced the heavy rains that devastated much of the northeastern part of the state on April 18th. Rain continues yet this morning, and we have accumulated 5.63 inches here at the research center in a little less than a week. Rivers and creeks were already beginning to rise even before the rainfall on the 18th, and that storm plus additional rainfall since has caused numerous levee breaches on the Kaskaskia River and its tributary creeks in the Vandalia area. The beautiful lake in the second photo above would be cropland under more normal conditions.

Needless to say, fieldwork has been at a standstill, and it will take several days of warm temperatures, sunshine, and wind before anyone will get back into the field. I suppose one advantage to being located on an agronomic research station is that I get to experience the same frustration as the crop producers I serve, when unfavorable weather conditions throw us a curve ball. On our corn planting date trial we have already missed the April 1 and April 20 planting dates, and are past the April 15 date on our soybean planting date trial.

After a few days of sunshine, steady breezes, and almost pleasant temperatures, most of the ponded water in fields has either evaporated or finally soaked into the ground. The soil surface certainly can't be called dry, but it has become firm enough that we could get into the fields without cutting ruts and apply nitrogen to the various wheat trials here at the research center. Wheat development throughout the region is definitely variable this year, with some fields approaching  Feekes Growth Stage 6 (jointing) while others are barely into Feekes GS 4 (end of tillering). Factors contributing to variability include planting date, variety, nitrogen fertilization rate and timing (both residual from 2012 and what was applied this winter), as well as field topography and drainage. Overall development is probably running a week or two behind normal, or close to a month behind what it was last year at this time.

In my March 20 blog entry, I had commented upon last fall's soil nitrate monitoring study. Preliminary testing early this spring indicates that there has been some leaching of residual nitrate down through the soil profile during the winter and early spring months, as reported by Dr. Emerson Nafziger in the April 2 Bulletin article. With soils now drying out and corn planting just around the corner, we will begin a broader re-sampling the same field areas that were sampled last fall to get a better idea of how much N may still be available for this summer's corn crop.

For the past several decades, one of the first sure signs of Spring has been the arrival of the season's first issue of the U of I Pest Management & Crop Development Bulletin, affectionately known simply as "The Bulletin". This weekly newsletter provided current updates on crop production and pest management issues from March through November each year. Up until 1997, The Bulletin arrived as a paper copy delivered by the U.S. Postal Service. Since 1997, subscribers have received an email notification each week that a new issue was available to view online, or download and print. Also since 1997, archived copies of each week's issue have been available online.

Constantly evolving technology is once again changing the way that The Bulletin is being produced and distributed. New distribution methods, such as an RSS feed, allows information to be uploaded and accessed on a daily basis, rather than having to wait an entire week for a new issue to be produced. As a result, The Bulletin will no longer be published on a weekly basis, and subscribers will no longer receive an email reminder when new information is published. Instead, you will need to subscribe to the RSS feed . Once you do, you will be automatically notified each time a new article is posted, and you can have new articles automatically downloaded to your computer, tablet, or smart phone.

For more information on the new format and how to subscribe to The Bulletin RSS feed click here.

Last year at this time soils were dry, temperatures were in the 80's, and growers in southern and central Illinois were pulling into the fields with corn planters. Flash forward 12 months and we have standing water in many fields, and potential snow flurries predicted for early next week. As a result, there is zero field work occurring other than some wheat nitrogen applications in fields that have better drainage, or may be frozen early in the morning. Currently the wheat crop is around Feekes Growth Stage 3 (tillers formed, breaking dormancy), whereas last year at this same time we were well into Feekes Growth Stage 5 (leaf sheaths strongly erect – typically the optimum time to apply nitrogen if it is going on as a single application).

As you drive around, you can observe some fields that are becoming discolored. You can often see varietal differences, as shown in the image above taken in the Wheat Variety Testing trial here at the Center. The problem is probably due to either wheat spindle-streak mosaic virus or wheat soil-borne mosaic virus. Both are viruses vectored by fungi in the soil, and plants should grow out of the problem as temperatures warm and soils dry.

Last fall Drs. Emerson Nafziger and Fabian Fernandez initiated a state-wide soil sampling survey to measure residual soil nitrate levels left due to last summer's drought and low corn yields. Preliminary results of that sampling were reported in the December 7, 2012 issue of the Bulletin crop newsletter. 

Their intent is to resample those fields in the same areas this spring to try and estimate how much nitrate might still be available for use by this year's crop at planting time. Obviously, most of the soils in the southern third of the state have been saturated much of the winter. While this has had the positive effect of recharging subsoil moisture following last summer's drought, one negative effect is the  increased likelihood that much of the nitrate has leached out of the root zone. If soils remain saturated as temperatures warm, the risk of nitrate loss through denitrification will also increase. As we get closer to planning time, we will begin resampling select fields that had high nitrate levels last fall to determine their status this spring.