This shot depicts two of the quintessential elements to high yield corn production.UNIFORM EMERGENCE and UNIFORM SPACING.If you want to grasp a better handle on how uniformly your crop emerged in 2009 go out into your fields and start measuring stalk diameter.Take a close hard look at the uniformity of stalk diameter in the above photo.There is a definitive correlation between stalk diameter and emergence.If you are finding too much difference in stalk diameter in your fields then you need to start asking yourself these questions ?
Did you push your planting date (in that was the field really fit for planting - there was more evidence of sidewall smearing in more corn fields in the spring of 2009 than I've personally seen in a decade),did you plant deep enough ( ideal planting depth is between 1 3/4 and 2 1/4 inches,are you getting too much planter bounce( ideal planting speeds are between 5 and 6 mph depending on planter type,are you leaving your fields level enough ,are you clearing sufficient residues( with trash whippers)to avoid seed furrow pinching and improve seedbed temperatures,are your units properly calibrated,are your double disc openers worn too much ( they should have at least 2 and 3/4 inches of contact at their front cutting point and they should be at least 14 7/8 inches in diameter,are your depth gauge wheels properly shimmed in, have you installed Seed Firmers and did you check both your closing wheel alignment and down pressures.NOTHING BEATS UNIFORM EMERGENCE FOR HIGH YIELD CORN PRODUCTION !

The greater degree of stem diamter uniformity you find in your fields the greater degree of higher yield performance you'll achieve.If you want to score yourself on how uniformly you're getting your crop to emerge I'd suggest purchasing a micrometer for measuring stem diameters.The above photo illustrates how stalk measurements can be taken with a micrometer.( Photo - Courtesy of the Pioneer Agronomic Image Library
DesMoine Iowa )