Here's A Tip

Tip fill in corn is a debated topic that is filled with more emotion than fact.  As a producer I feel better when my corn crop is filled right to the tip.  It makes me think I have done everything possible to grow a strong crop with maximum yield potential.
And a well filled ear will win 1st prize at the local fair every time.

As an agronomist I have a different attitude because of my understanding how a corn plant works.  A less than perfect tip can be the result of several complicating factors that do not always compromise yield potential.

The number of kernels is set at silking time.  A healthy plant with adequate water and sunshine will fertilize the maximum number of kernels possible.

The tip silks are the last silks to emerge from the ear.  This picture shows tip silks that were not fertilized.
If the plant is under moisture stress it will abort the tip kernels.
If the plant is under severe heat stress, like we had the last week in July, kernel tip abortion can happen because pollen shed occurs too fast and tip silks emerge too slow.  When the tip silks finally emerge, pollen shed is finished.  This is known as missing "nick" in the seed corn production business.
If moisture stress occurs after silking the corn plant will decide to abort fertilized kernels at the tip in favour of saving kernels further down the ear.  This is a self preservation mechanism.

But all is not necessarily lost because genetics can play a major role.   Some hybrids don't have it in their gene pool to give a nice pretty tip.  They routinely will show a little "dirty nose".

Here are a couple of new hybrids, P9910XR and P9760HR, that may not have it in the family tree to fill their tips.  Does this make them inferior?  If you grow corn to win field crop competition at the fair, then the answer may be yes.  But, my experience has taught me that this style of hybrid can yield very well.

The reason is the corn hybrid doesn't care what it's tip looks like.  It carries on by can packing many rows of deep kernels around the cob.  The few tip kernels missing are more than made up for by deeper, heavier kernels lower down the ear.
They may not be the prettiest girls at the fair, but you should take them home anyway.