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Corn Newsletter : 2016-23
2016 Ohio Wheat Performance Test Available Online
A pdf of the 2016 Ohio Wheat Performance Test can be found at the Soybean and Small Grain website at: http://stepupsoy.osu.edu/node/35. A sortable version of the Ohio Wheat Performance Test can be found at: http://www.oardc.ohio-state.edu/wheattrials/
Test results are for 72 soft red winter wheat varieties grown at five Ohio locations (Wood, Crawford, Wayne, Darke, and Pickaway County). Variety selection should be based on disease resistance, average yield across test sites and years, winter hardiness, test weight, and standability. Overall, grain test weight averaged 58.4 lb/bu (compared to an average test weight of 56.3 lb/bu in 2015). Grain yield averaged between 97 and 119 bu/acre at the five locations.
Spraying Insecticides on Soybeans and Honey Bees
Although soybean aphids remain at low levels in Ohio, we are aware that many growers are adding insecticides to spray tanks when applying fungicides for plant health purposes and even late applications of herbicides because: “Well, I’m going over the field anyway so I thought I’d add an insecticide for insurance purposes! The insecticide is relatively cheap and soybeans are worth so much!” As we have always stated, we do NOT recommend this practice, and feel an IPM approach is much better for everyone and everything, including the environment. We do NOT recommend an insecticide application unless there is a REAL need.
However, we realize that this is being done. What we need to address is an extremely important and related issue, and that is the need for growers and custom applicators to protect bees when spraying insecticides on soybeans (or any crop or insect pest for that matter). The need to do this is present whether the insecticide is being sprayed for an actual pest, or when being sprayed for “insurance purposes”! Remember that most insecticides have a caution statement on their label about spraying around bees and blooming crops. The typical statement is: “This product is highly toxic to bees exposed to direct treatment or residues on blooming crops or weeds. Do not apply this product or allow it to drift to blooming crops or weeds if bees are actively visiting the treatment area”.
How often do bees visit soybeans? Soybeans bloom flowers produce a very sweet nectar that, depending on conditions, can be highly attractive to bees. However, it can be difficult to appreciate how much foraging is really occurring because both the bees and flowers are hidden below the canopy. In a survey of honey produced in the summer of 2014 soybean pollen was found in nearly half of honey samples—a strong indication that bees are indeed foraging in soybean fields.
Further, bee pollination has been shown to increase soybean yield by as much as 18% in some studies, so it really can be counterproductive to risk killing bees visiting soybeans with an “insurance” application of insecticide.
The Ohio Department of Agriculture addresses this concern under Regulatory Divisions & Programs, Plant Industry Division, Pesticide Regulations, Law and Statues, Plant Industry 901:5.
(B) No person shall:
(15) Apply or cause to be applied any pesticide that is required to carry a special warning on its label indicating that it is toxic to honey bees, over an area of one-half acre or more in which the crop-plant is in flower unless the owner or caretaker of any apiary located within one-half mile of the treatment site has been notified by the person no less than twenty-four hours in advance of the intended treatment; provided the apiary is registered and identified as required by section 909.02 of the Revised Code of Ohio (http://codes.ohio.gov/orc/909.02), and that the apiary has been posted with the name and telephone number of the owner or responsible caretaker.
(16) Apply pesticides which are hazardous to honey bees at times when pollinating insects are actively working in the target area; however, application of calyx sprays on fruits and other similar applications may be made.
We continue to advise that growers and applicators maintain good communications with bee keepers near their fields to prevent and limit unintended problems. A listing of registered apiaries can be obtained from the Ohio Department of Agriculture. The website is http://www.ohioagriculture.gov/plant/curr/ap/plnt-ap-index.stm. The list can be requested via e-mail to the address firstname.lastname@example.org
Below are some specific recommendations for environmental and pesticide factors that will lessen the potential for injury to bees.
1) Drift of pesticide not only can injury non-target plants but bees or other insects located within the canopy of non-target plants. Follow all precautions related to drift such as wind speed, direction identifying risk potential of neighboring crops. Recently we have seen more fields with filter strips or other conservation areas along borders. Plants in these border areas may be in bloom and harboring foraging bees. Drift or spray overlay has the potential to cause injury to bees and should be considered in pesticide applications.
2) Timing of application can limit bee injury. Applications in the evening or early morning are generally best. Bees are less active at these times of the day. Other times when the blooms are less attractive and lower bee activity are acceptable as well.
3) Formulations of pesticides will make an impact on toxicity. Dust and wettable powders are more toxic than emulsifiable concentrates. Ultra low volume applications versus a regular application are generally more toxic. No repellents can be added to tank mixes that will keep bees away from treated areas.
4) Toxicity of pesticides can differ. Most pesticide have been tested with bees in laboratory settings. Keep in mind there can be differences in field results versus laboratory results due to environmental factors as well as the sensitivity difference in populations of bees.
“Tassel Ears” Sightings in CornAuthor(s): Peter Thomison
Tassel Ears” (Figure 1) are showing up in corn fields around Ohio. Corn is the only major field crop characterized by separate male and female flowering structures, the tassel and ear, respectively. In most corn fields it is not unusual to find a few scattered plants with a combination tassel and ear in the same structure - a "tassel ear". The ear portion of this tassel ear structure usually contains only a limited number of kernels.
Tassel ears often appear on tillers (suckers) arising from plants with normal ears and tassels. These tassel ears are produced at a terminal position on the tiller where a tassel would normally appear. However, tassel ears may also be produced by individual plants and often occur in shorter spindly plants associated with delayed emergence and uneven crop development. Tassel ears are often produced by tillers that result when the plant’s growing point is destroyed or injured by hail, wind (green snap), animal feeding, frost, flooding, herbicides, and mechanical injury. Some hybrids may also be more prone to tiller under certain environmental conditions and these tillers may give rise to tassel ears. Low plant density may also promote tillering.
Tassel ears are a reminder that the male and female parts of the corn plan are structurally very closely related. Wild progenitors of corn-teosinte spp. have complete flowers tassels and silks together. These can be crossed with Zea mays (normal corn).
There has been some speculation that a fungal disease called "crazy top" may be responsible for this abnormal ear condition. Crazy top does affect the appearance of tassels and ears but the symptoms are distinctly different from those of the tassel ear phenomenon. Crazy top causes the tassel and/or the ear to become leaf-like. In severe cases, the whole top of a plant and ears are replaced with a mass of leaf-like structures. Visual symptoms and more details concerning crazy top are available on the online at http://u.osu.edu/mastercorn/crazy-top-of-corn/
For more on diagnosing tassel ears and other ear anomalies that start to appear in corn fields during kernel development and crop maturation, check out “Troubleshooting Abnormal Corn
Ears” available online at http://u.osu.edu/mastercorn/
Figure 1. Tassel ears usually occur on a limited number of plants within a field (Source: Sam Custer, Darke Co. Extension, August 2016.)
Two New Products Available for Twospotted Spider Mite Management (One for Each Spot)
With continued dry weather, the pest we’ve been getting the most calls about is the spider mite. This is just a reminder that vigilant scouting for this pest is a good idea right now. It is also important to re-scout 5 days after treatment because many products will not kill the eggs, and populations can resurge. Any nescessary followup treatment should be made with a product with a different mode of action to reduce resistance development (so, for example, if you used something with bifenthrin the first time, you might switch to Lorsban the second time, or vice versa). This link will take you to the OSU publication on spider mites in soybean:
There are two miticides that are newly labeled for spider mite management in soybean and/or some types of corn: Agri-Mek from Sygenta and Zeal from Valent. We at OSU have not tested these products yet, but are currently running trials with both of them in northwestern Ohio. Thanks to all of our readers who helped identify suitable locations!
Western Bean Cutworm Update
On another note, adult western bean cutworm trap counts are declining, having past their peak for the summer. But scouting is still relevant as the later moths continue to lay their eggs. Counties near Lake Erie have had particularly high trap counts. Threshold populations on corn plants should be treated before larvae have a chance to enter the plants. To scout for eggs or larvae, choose at least 20 consecutive plants in 5 random locations and inspect the uppermost 3–4 leaves for eggs, as well as the silks for larvae if tassel has emerged. Be sure to inspect different areas of the field that may be in different growth stages. For field corn, if 8% or more of the plants inspected have eggs or larvae, consider treatment. For sweet corn, consider treatment if eggs or larvae are found on >4% of plants for the processing market or on >1% of plants for fresh-market. Find more information at:
NW Ohio Precision Ag Sprayer Day - Next TuesdayAuthor(s): Eric Richer, CCA
The Northwest Ohio Precision Ag Sprayer Day (clinic) and Pesticide Recertfication will be held next Tuesday, August 9th at the Fulton County Fairgrounds located at 8514 State Route 108, Wauseon, OH just off of the Ohio turnpike. Program runs from 8 am to 3:30 pm and cost at the door is $40. Offering 3.5 hours of Ohio Commercial (2c) and Private (1) recertfication as well as 5 hours of training for Certified Crop Advisors in IPM. Additionally, for our friends to the North who farm in Michigan, 5 hours of Michigan pesticide recertification will be offered. Great demos from Hardi, Deere, CaseIH, TopAir, Rogator, CapstanAg, and Gaerte Ag Service among other educational sessions on drift management, calibration, new technology, and nozzle selection.
About the C.O.R.N. Newsletter
C.O.R.N. Newsletter is a summary of crop observations, related information, and appropriate recommendations for Ohio crop producers and industry. C.O.R.N. Newsletter is produced by the Ohio State University Extension Agronomy Team, state specialists at The Ohio State University and the Ohio Agricultural Research and Development Center (OARDC). C.O.R.N. Newsletter questions are directed to Extension and OARDC state specialists and associates at Ohio State.
The information presented here, along with any trade names used, is supplied with the understanding that no discrimination is intended and no endorsement is made by Ohio State University Extension is implied. Although every attempt is made to produce information that is complete, timely, and accurate, the pesticide user bears responsibility of consulting the pesticide label and adhering to those directions.
CFAES provides research and related educational programs to clientele on a nondiscriminatory basis. For more information, visit cfaesdiversity.osu.edu. For an accessible format of this publication, visit cfaes.osu.edu/accessibility.