C.O.R.N. Newsletter 2004-37

Dates Covered: 
October 26, 2004 - November 9, 2004
Editor: 
Barry Ward

Fall Applied Nitrogen

Authors: Robert Mullen

Those producers that are considering fall applied N need to keep a few things in mind. First and foremost, fall applied N is not recommended by the University due to the potential losses that can occur. Not only does this pose an environmental risk, the economic implications can be significant. Depending upon winter and spring conditions, N applied this fall may not be around when the crop is ready to utilize it. Primarily leaching (confined to cooler weather) and denitrification (typically experienced due to wet conditions in the spring) are the two loss mechanisms that occur. If N is to be applied this fall make certain that soil temperatures are well below 50 F and that ammonia forms of N are used, this will inhibit nitrification (conversion of ammonium to nitrate – which is mobile and susceptible to leaching). The use of a nitrification inhibitor may be used to keep N in the immobile ammonium form. Nitrification inhibitors are not cheap – costing upwards of $7/acre. Depending upon the winter, they can result in significant savings. Still the best bet is to wait until spring and apply N preplant or sidedress.

Soybean Aphids and Buckthorn

Authors: Ron Hammond

During the past week, buckthorn, Rhamnus sp., considered the primary overwintering host of the soybean aphid, was located in numerous sites throughout Ohio with varying size populations of aphids. The two most common and likely overwintering hosts are the common buckthorn, Rhamnus carthartica, and the glossy buckthorn, Rhamnus frangula. These sites were all planted sites, that is, planted by people rather than in natural settings. Four were in arboretum or garden settings, while the other was at a highway intersection; all were very large bushes to small trees in size. The C.O.R.N. newsletter from October 12-19 had an article discussing the larger populations of winged soybean aphids being collected in the Midwest. These aphid populations on buckthorn in Ohio support what other states are finding, and adds to the prediction of aphid problems next summer. The following site discusses identification of the common species of buckthorn: http://btny.agriculture.purdue.edu/buckthorn/page3.asp
The most important characteristics for Rhamnus carthartica are green in color, the presence of large black berries, and having branches ending in spines. We are currently getting the aphids correctly identified; however, at this time we believe them to be soybean aphids.

Fall Sampling for Slugs

Authors: Ron Hammond

Fall sampling for slugs should be in high gear right now. We are currently finding large populations of adult gray garden slugs in numerous fields. This is the time to determine which fields have significant populations, and which do not. See the C.O.R.N. newsletter from Sept 27 –Oct 4 for discussion of fall slug sampling.

Still Planning a Fall Herbicide Application?

Authors: Mark Loux

There is still plenty of time to apply herbicides this fall for control of winter annual, biennial, and cool-season perennial weeds. This week’s weather should be extremely favorable for herbicide activity. A previous article in C.O.R.N. contained information on the most effective treatments (“The Basics of Fall Herbicide Treatments”, Sept 27 issue). Fall herbicide treatments can generally be applied through the end of November for control of most winter annual weeds. Dandelion can be controlled into late November also, as long as the plant appears to be mostly green and actively growing still.

No-Till Wheat Emerged With No Burndown Herbicides Applied?

Authors: Mark Loux

For those of you who ignored our suggestions about the importance of a preemergence glyphosate application in no-till wheat, and now have emerged wheat and winter weeds, all is not lost. Several wheat herbicides are labeled for fall application, including Sencor (up to 2 oz), Peak, Harmony Extra, Buctril, and dicamba. Of these, Harmony Extra and Peak may be the most effective across a range of winter annual weeds. DuPont suggests application of 0.3 oz/A of Harmony Extra this fall, followed by application of an additional 0.3 oz/A next spring if needed (or another herbicide as weed populations require). Wheat should be in at least the 2-leaf stage for a fall application of Harmony Extra. We conducted one study in 2002/2003 to determine the effect of fall-applied wheat herbicides on wheat yield in the absence of weeds. None of the herbicides labeled for fall application caused yield reduction, but application of 2,4-D did reduce yield. This would suggest that use of products containing 2,4-D should be avoided when making fall applications (some are labeled for fall application). While we have limited experience with fall herbicide applications in wheat, they should be considered where the population of winter weeds appears to be dense enough to suppress wheat growth this fall or next spring. Unfortunately, we expect fall herbicide applications to have limited value for control of dandelions.

Potassium Availability this Fall and Winter

Authors: Edwin Lentz, Robert Mullen

Several reports are coming in from local retailers that potassium availability may be low this fall and winter. As mentioned in an earlier CORN article if soil test levels are well above the critical value and maintenance applications have been conducted in the past, do not worry about applying potassium this fall or next spring. Since spring potash applications are as effective as fall in meeting crop needs, one may want to wait until spring to apply potash on soils with lower test levels. By spring, potash may be more economical and available compared to present times. In fields that are below the critical level, potash should be added to starter fertilizers as well as a general application for corn production.

Adapting Silage Silos for Dry Grain Storage

Authors: Alvin Dale, Bruce McKenzie, Don Jones

Silo structures for silage have been used for grain storage, both wet and dry, for a number of years. Although the first cost of a concrete or steel silo for grain storage is usually somewhat higher than the cost for a comparable volume round metal bin storage, the ease of adding concrete hoppers, the more efficient space utilization of the tall silos, and a structural form considered by many as more permanent, has appealed to many elevator and some farm operators.
As farm operations change from year to year, a number of farmers find themselves with a silo that is not being used for silage. The structure may be too small, in the wrong location, or abandoned as enterprise organization changed. This publication is directed to the possible evaluation and adaptation of such silos for dry shelled corn and/or small grain storage.
General Considerations
There are a number of general considerations that need to be weighed in approaching the evaluation of an existing silo for possible adaptation for dry grain storage. These include:
1. The silo must be in sound structural condition, and hooped or reinforced sufficiently to store dry shelled grain.
2. The silo must have a roof.
3. The silo must have a concrete floor, preferably built to a height above that of the surrounding soil grade around the silo.
4. The walls must be reasonably moisture tight. The doors and walls must be reasonably air tight to permit forced aeration.
5. The silo must have a fill system that will minimize grain damage.
6. The silo must be equipped with an aeration system adequate to condition dry grain.
7. The silo must be equipped with an unload system that will withdraw grain from the bottom center point--side tapping for gravity outflow is only permissible if the manufacturer will so certify.
8. The silo should be in a favorable location for incorporation into a sound and efficient long range grain storage facility.
For a look at the complete publication on adapting silage silos for dry grain storage, go to:
http://www.agcom.purdue.edu/AgCom/Pubs/AE/AE-93.html

Archive Issue Contributors: 

State Specialists: Dennis Mills (Plant Pathology), Ron Hammond (Entomology), Mark Loux (Weed Science), Robert Mullen (Fertility), Ed Lentz (Agronomy & Seneca Co.), Bruce Mckenzie, Don Jones and Alvin Dale, Agricultural and Biological Engineering, Purdue; Extension Educators: Roger Bender (Shelby), Barry Ward (Champaign), Steve Foster (Darke), Harold Watters (Miami), Glen Arnold (Putnam), Howard Siegrist (Licking), Todd Mangen (Mercer), Gary Wilson (Hancock)

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.