Extension Educator, Commercial Agriculture
May 30, 2012
May 30, 2012
May 29, 2012
This study has two hybrids, a full season and a shorter season, and will also include a fungicide treatment on each planting date.
May 28, 2012
Stephanie Porter sends a weekly summary of diseases and plant injuries diagnosed from samples submitted to the University of Illinois plant clinic. Visit the plant clinic site to learn all that they have to offer
In this week's report several corn seedling samples had been diagnosed as chemical/herbicide injury. I noticed several examples of herbicide injury at the NIARC as well. Dr. Aaron Hager recently shared that the increased observation and inquiries from herbicide injury appears to be statewide.
From Aaron's article; "Many postemergence corn herbicides routinely cause some corn injury," said Hager. "Some growers, however, have the impression that this year there is a bit more injury than usual.
Hager said that several factors can affect the sensitivity of corn to injury from postemergence herbicides, including:
• Hybrid: Hybrids have varying sensitivity to herbicides labeled for use in corn. For example, some corn hybrids are sensitive to specific ALS-inhibiting herbicides and tend to exhibit considerable injury following herbicide application. Many corn herbicide labels (especially labels of postemergence corn herbicides) carry warnings that certain corn hybrids could be sensitive to the active ingredient.
• Environmental conditions: High air temperatures and relative humidity levels favor rapid absorption of foliar-applied herbicides, but some environmental conditions can induce crop stress, slowing the rate at which the crops metabolize the herbicide and leading to increased herbicide-related injury. For example, cool air temperatures and wet soil can induce crop stress.
• Spray additives: Crop response may be enhanced when spray additives are applied with a postemergence herbicide or tankmix combination because of the increased rate of herbicide absorption into the plant. Be sure to read all label suggestions and precautions related to spray additives that should be either included or avoided when applying herbicides postemergence.
• Contamination: Herbicide residues from prior applications may be applied inadvertently with the postemergence corn herbicide. These residues, either alone or in combination with the postemergence corn herbicide, may enhance the amount of corn injury. The type of contaminant and the dose at which it is applied affect the severity of the corn response to spray contamination."
Dr. Hager's article can be read in its entirety here
May 26, 2012
May 24, 2012
May 23, 2012
May 18, 2012
At the NIARC we planted our last corn trial and will finish all planting in a few days. Today the plant diseases group was at Shabbona planting their study; also pre-emergent herbicides were evaluated at the V2 stage in our corn. Our trials are almost grass and Lambsquarter free. Our researchers have even suggested bringing more seeds of those weeds to plant for future years. No such problem with Giant ragweed, our most challenging weed. It continues to emerge and survive in several of our treatments. One study of interest this year is the return of a plot that was in Switchgrass for several years to corn and soybean production. We are looking at challenges producers may face if they attempt to bring acreage in perennial grasses back into production. The plot has received a glyphosate burn-down and is planted (in both corn and beans in 30"rows) but as the picture illustrates, the Switchgrass is far from dead. We will keep you abreast on what we learn from this study.
May 17, 2012
May 16, 2012
Last evenings best performance may have been the Lightening "light" show courtesy of Mother Nature. The quick moving storm did not yield enough rain to keep us out of the field. Today at the NIARC soybean pre-emergence herbicides were applied in one study, 0-12 inch and 12-24 inch soil samples were collected prior to fertilizer applications in another study. Dr. Brian Diers soybean germplasm evaluation trials were also planted this afternoon. While staking out the location for the final date of planting in our corn study, I noticed our earliest planting corn is rebounding from earlier cold temperature damage to its leaves. A quick reminder to stay alert for Black cutworm damage came from an unexpected phone call. My brother shared that the Indian corn that he had started in his hothouse and transplanted in his garden had been "cut off at the soil line". I didn't get the chance to confirm my diagnosis but am fairly certain Black cutworm is the culprit. Be alert if you have high risk fields.
May 15, 2012
With almost 90% of the corn planted in Illinois we are playing catch up at the NIARC. Replicated studies planted with a four row planter and different treatments is a slower process when compared to planting with a 12 row (or larger)planter across large fields! Activities at the NIARC yesterday included the Variety testing team who planted their soybean variety trial; the entomology researchers pulled in at 8:30 pm and got an early start this morning to plant their soybean studies as well. Lyle Paul shared his expertise in designing and spraying a pre-emergence herbicide trial. Expect lots more action today, I'm off to the fields!
May 11, 2012
Stripe rust of wheat has been a topic for several weeks in the Illinois Bulletin. The disease was initially reported in southeastern Missouri and Arkansas. It then progressed into southern and central Illinois and this week was identified by Norman Smith on susceptible germplasm in the wheat variety testing trials at the NIARC. Stripe rust symptoms first occur as chlorotic linear streaks on the leaves. Later on, yellow to orange pustules will develop in a linear fashion ("stripes") within these chlorotic streaks. While most commercial varieties appear to have adequate resistance to the disease, now would be the time to scout. Most wheat fields in northern Illinois have started to flower (Feekes 10.51) If Stripe rust is present fungicides registered for control of Fusarium head blight (scab), such as Caramba, Prosaro, and tebuconazole products (e.g. Folicur and others), would be the products to apply for protection against stripe rust if needed. In addition to suppressing Fusarium head blight, these products have excellent efficacy against stripe rust, and their labels allow applications during flowering (unlike other products that may not allow applications past Feekes 10.5 - heading).
Today at the NIARC the oat testing trials were treated with a herbicide, and we hope to plant date of planting studies in both corn and soybean.
May 10, 2012
May 8, 2012
Rainfall in northern Illinois for the preceding four days has ranged from less than ¼ inch to 5+ inches. While standing water is not currently an issue at the NIARC it is for others in our area. Flooded and saturated soils cause anoxic conditions (limited oxygen) for the plants and importantly, the root systems.
Dr. Bob Nielsen at Purdue authored an article on the "Effects of Flooding or Ponding on Young Corn", the 2011 article can be found in its entirety at the following URL
Excerpts from the article shared the following generalizations. I'm careful to state "generalizations" because I am one who has been burned by a recommendation that I once made on a ponded field, stating with almost certainty that the corn would not survive. In fact, the water receded and the field dried comparatively quickly, the corn survived and yielded in the 160's. I am reminded of this annually whenever I interact with the farmer. So, there are few absolutes but;
The survivability of the seedling can be determined by examining the color of the growing point of the corn plant. The radicle (root) and coleoptile (shoot) should appear white or cream colored. Surviving plants usually resume growth within three to five days after the water recedes.
May 7, 2012
May 4, 2012
May 1, 2012