Full Scouting Report for July 16, 2012

WEATHER UPDATE
Over the weekend rain was very welcomed near Constantine, MI, but drought conditions continue in most of Michana.  According to the Drought Monitor most of Michana remains in the Severe Drought category.  The southern parts of Elkhart and LaGrange Counties are in Extreme Drought state.  Another level remains - Exceptional Drought.  

Goshen has received 4.16 inches of rain since April 1.
LaGrange has received 1.88 inches of rain since April 1.
Three Rivers has received 7.45 inches of rain since April 1 (4.18 of which was in April).

This is, by far, the most severe drought in recent history for our area.  Some weathermen have said it's the worst drought in the last 100 years.  Bad is bad, and this is BAD.  But you don't have to read this report to know that.  I do hope you find the read interesting, amazingly insects continue and a few green fields remain.

CORN
High temperatures are effecting irrigated acres.  As the water sits on the corn leaves in direct sun it causes Sun Scald - in effect, burning or cooking the corn leaves.  In this field the scald was closer to the center of the pivot, where the irrigation moves slower and the water sits on the corn leaves longer.

The dry-land corn field we checked for pollination near Millersburg, IN two weeks ago continues to look good.  The ear pollinated with very few blanks.

This field is "fired" up to two leaves below the ear.  If rain falls before the ear leaf dies, it should fill out the ear.  While the ear is small, it is doing amazingly well considering the lack of rain this year!

Unfortunately, many dry-land fields have already reached disaster.  Once the ear leaf dies the plant is no longer delivering nutrients and moisture to the ear.  The kernels, if they were pollinated, will abort development and the whole plant will continue to die.  Rain after this point is of no use to future yield.

Plans for corn fields have changed for some farmers where the crop can be salvaged as silage.  If you plan on cutting corn for silage consider having the plants tested for Nitrates.  In drought stricken corn, toxic levels of nitrates can be stored in the lower stalk.  To have the plant tested, cut the plant at the same level you would cut it for silage and bring the whole plant in to the office.  We'll send it in to the lab for analysis.
Another note: if you cut a field for silage and expect to collect crop insurance - contact your insurance agent first, you may need to leave a check strip to be inspected at a later date.

SOYBEANS
Two-Spotted Spider Mites have now been found in irrigated fields.  Scout all fields for a sand-blasted appearance on the upper leaves - take a white sheet of paper with you!  Click here for detailed scouting info on Two-Spotted Spider Mites.

The second generation of Bean Leaf Beetles are feeding on soybeans.  Not only will this generation feed on the leaves, but they will also attack pods.  During reproductive stages the threshold of defoliation is 15 percent (down from 40% pre-bloom).  Or if 10 percent of pods show signs of damage.  This field, near Bristol, IN, has less than 5% damage.

Bean Leaf Beetles can be different colors, but regardless of color, all Bean Leaf Beetles have a distinct black triangle behind the head on the wing covers.

Sudden Death Syndrome has been found in LaGrange County.  This disease turns the leaves yellow in between the veins and leaves quickly die and drop off.  The disease actually infects the plant early in the season and symptoms show up under stress later in the season.  (Sorry, I forgot to take a picture : / )

In the same field, a few Fall Armyworm were also found feeding on soybean leaves.  (Again, sorry no photo.)

On a positive note: There have been no Soybean Aphids or Asian Rust found in our region this year.

Thanks for scouting with us!

The Shake, Rattle and Roll of Corn Pollination

One way to check if the kernels on the ear were pollinated is to wait a couple weeks and see which ones plump up.  If you're impatient you can check the week after pollen shed by using the Shake Test.  

Here are the instructions for the Shake Test:
Select an ear with silks emerged and pull it off the stalk.  (See the anthers on the silks!)

Take a knife and cut 1/4 inch slices off the bottom of the ear until the bottom of the cob (and kernels) can be seen.

Very carefully peel the husk leaves off of the ear.

Then hold one end of the ear and shake it up and down to see how many silks fall off.  

Each silk that falls off represents a kernel that has been fertilized. 
This particular ear has not been pollinated yet.  

That's the Shake Test, Thanks for scouting with us!

Corn Pollination

Tassels are emerging in early planted corn.  While it is good to see the corn progressing there is concern on dryland corn acres that pollination will not occur properly.

Under drought stress corn tassels emerge early, while silk emergence is delayed, causing pollination failure.  Silks are actually hollow tubes that "catch" the pollen from the tassel and carry it down to the kernel.  About an inch of silks should be visible to properly receive pollen.  When pollination fails there are blank kernels, or in worse case scenarios, blank ears.  The "Silking" growth stage of corn (when silks are receptive to catching pollen) lasts approximately 4 days. 

The good news for the field scouted in Millersburg, IN for this post is that pollen shed and silk emergence is coridnated.  (Yeah!)  There is a 'pollination-shake test' that can be performed at the end of the silk stage to confirm pollination ... look for more information on that next week.

A sign pollen shed is ending is finding empty anthers from the tassel on corn leaves and on the ground.

As we all know, pollination is only one more step in the process, if drought conditions continue the plant can still abort kernels. 

Weather Update: While the rains over the weekend were very much appreciated, they were not enough to bring us out of our current condition of severe drought stress (unofficial opinion, the updated Drought Monitor report comes out in three days).  Areas in southern Michiana received upwards of .7 inches of rain, the least unofficially reported to Edd's was 2 tenths near Goshen. 

Thanks for scouting with us!