Hoegemeyer - the right seed

Looking out the window this morning it sure doesn’t seem like mid May.  The weather has been cool and wet for the most part and hasn’t allowed planting to progress as many would have liked.  The forecast for the next 10 days looks to be warmer and drier, meaning that planting will be in full swing.  I’m sure the crop on everyone’s mind right now is corn.  Getting corn acres in is important, but don’t forget that planting your soybeans early is a key to maximizing yield.  If you have access to two planters, using one to plant soybeans may pay off big in the long run.
According to UNL Agronomy professor Jim Specht a rule of thumb for increasing soybean yields is to “Have the soybean canopy green to the eye by the 4th of July.”  Early planting has proven to increase yield for a number of reasons.  One can be attributed to capturing solar radiation early in the growing season.  If the crop is out of the ground early it will have more time to capture the energy of sunlight and convert carbon dioxide into carbohydrates, protein, and oils, all adding up to increased yield (Figure 1). 

Figure 1. Comparison of development of soybeans planted at four dates in late June 2003 and 2004. The signs indicate when the 4-row strips were planted. (Photo courtesy of Jim Specht, UNL)

An earlier planting date will also increase yield by adding more nodes per plant.  Once a soybean puts on its first trifoliate leaf, it will add one node every 3.75 days.  This is relatively independent of temperature so those later planted beans will likely not “catch up” in terms of number of nodes developed.   Nodes are where the plant flowers put on pods so more nodes = more pods and more pods = more yield.  UNL research has shown anywhere from a 1 to 10 bushel per acre increase by planting soybeans early depending on spring weather conditions with an average increase of 3 bushels per acre over the last 7 years.  After May 1, producers lose between 1/4 and 5/8 of a bushel per day that soybean planting is delayed. 
 

If your operation has the equipment, try planting some soybeans along-side your corn this growing season.   Some of the most successful farmers are those who think outside the box and are willing to try new approaches in their farming operations.  Come harvest, early planted soybeans might just pay dividends.

Harvesting Drought-Stressed Corn for Feed

Here is a useful link on feeding drought stressed corn to livestock:

http://www.extension.iastate.edu/article/take-precautions-when-feeding-drought-damaged-corn-silage

Besides feed safety, there are agronomic considerations with removing plant matter for feed.  1) Soil erosion.  Sowing a cover crop into the bare ground will help prevent erosion and stimulate microbial activity during the long off-season.  2) Soil nutrient removal.  When stover is harvested, potassium is removed at a much higher rate than when just the grain is harvested.  Be prepared to soil test and fertilize to replace removed nutrients.  Another thing to consider is that nutrients removed from any given spot can vary based on the tonnage removed.  This can make it difficult to know how much to replace on a variable rate basis.  Here is a link for further information:

http://www.extension.iastate.edu/CropNews/2012/0727sawyermallarino.htm

Spider Mites in Corn and Soybean

Spider mites, most common in the drier parts of the corn belt, are being spotted further east this year due to the heat and drought.  Here are a few things to consider if you find spider mites in your fields:

1. Economic threshold is low for treating due to high commodity prices, but…
2. Most insecticides will not work.  Spider mites are in the arachnid family and options for control are relatively few.  Make sure you are applying a miticide or insecticide with activity on spider mites.
3. Pesticide application will likely destroy beneficial insects and does not control mites in the egg phase, so be prepared to make one or more follow-up applications.

Here is a link with more information: http://www.ianrpubs.unl.edu/pages/publicationD.jsp?publicationId=513

Corn Development

At the late dough or dent stage, there is still a lot of yield yet to be determined during the next few weeks.  If successful pollination has occurred and the plant is alive, a good rain could still help in a lot of cases.  The following table has been adapted from Iowa State University’s publication “Corn Growth and Development”.

Hello from the Eastern Region! Planting seems to be winding down with many growers finishing up soybeans by the end of the week. It truly is astonishing at how fast our crop can go in if given 10 days of favorable planting conditions. Corn emergence and overall field stands look good considering the temperature roller coaster that we were exposed to in late April. A few fields had reduced emergence from temperature imbibition chilling but nothing really out of the ordinary. Black cutworm larva activity seems to remain low for the most part with only a few fields requiring treatment but fields still need to be monitored for the next couple weeks. White grub activity seems to be increasing a little each year. No rescue treatments provide reliable control for this pest so the best advice is to remember any problem fields for the future as a preventative insecticide at or before planting may be justified.

Corn imbibition

Black Cutworm Tunneling into Base of Stalk 

White grubs feeding on corn roots below ground

Some reports of purple corn have been reported in Missouri. What causes this? Purpling of corn is evidence of a couple of things. For one, some corn germplasm just tends to exhibit more purple color as seedlings than others. But for those fields with significant visual purpling it is usually due more to environmental stresses like wet soils, compaction, cool temps, and others. The plants produce a larger amount of anthocyanin pigment under these conditions causing purpling. Restricted seedling root growth can also hinder the plant from phosphorus uptake as well. Typically most of these plants will recover with minimum yield loss once good growing conditions set in unless the symptoms are very severe.

Purple Corn

The last of the Hoegemeyer research replicated corn and soybean plots went in the ground May 14th compared to June 6th last year. What a difference in planting seasons! It is worth noting that growers should be aware that we are well ahead in terms of heat unit accumulation this year. Many insect species are showing up ahead of normal time frames. This may alter when and if they migrate into crops as food sources.  In general, a younger crop is more susceptible to insect injury than a more mature crop.
Now is the time to check fields for emergence and stand counts. Don’t assume that field off the beaten path is fine. Crusting of soil can form quickly with high temps and windy conditions, especially if the field was slightly damp at planting. It is only the middle of May so we are still in a window where any replant will be able to at least approach 90% of optimum yield potential, but the clock is ticking and each day now we lose significant bushel potential. Sunlight drives yield in our crops and delayed plantings will not be able to utilize full photosynthesis potential, especially as you move north where the growing season limits us.
 

DID YOU KNOW???  The state of Alaska is famous for being able to grow tremendous vegetables.  Cabbages get as big as beach balls with a record of 100 lbs. How is this so?  The trio of fertile soil, cool to moderate temperatures, and SUNLIGHT!  At one point during the growing season Alaska has close to 24 hours of daylight. This makes for one incredible photosynthetic factory!