A known observation and fact is that many growers miss the opportunity to capture better yield potential prior to planting the first seed.  Worn parts and improperly adjusted planters are some of the first reasons you give up corn yield.  It takes knowledge and time to inspect and adjust your planters to ensure that all seed is planted at the same depth, spacing and seed coverage to give your seed every opportunity to germinate and emerge withing 12 hours of each other.  Listed below are some pointers I picked up from Missy Bauer, Farm Journal agronomist at the Georgia Corn Shortcourse a few years ago.

Functional areas and parts to check:

• Seed Transmission System
  • Clutch assembly
  • Beargings/sprockets/idlers
  • Chains
• Wheels & Tires
  • Lugnuts/bearings
  • Tire air pressure
• Fertilizer attachments
  • Openers & bearings/blades/shoes
  • Fertilizer hoses
  • Piston or squeeze pump
• Down Pressure Spring Assembly (VERY IMPORTANT)
• Parallel Arm Linkage
  • Measurements between arms
  • Bolts & bushings
  • Shape of hole on parallel arms (circle or egg shape)
• Row Unit Sprockets
  • Meter Disconnect lever (lines up correctly)
  • Moving freely
• Drive Chains
  • Lubricated & in good condition
  • Drive rollers/ idler/ idler springs
  • Check for grooves in rollers
• Row cleaners
  • Bearings
  • Free movement up and down
• No till coulters
  • Bearings
  • Cutting edge
  • Centered on hub
  • Check depth (must be 1/4 inch higher than opening discs)
• Gauge Wheel Assembly
  • Gauge wheel arm condition
  • Walking gauge wheel attachments
  • Rubber tire
    • good condition
    • runs true and has contact with disc blades
  • Bearings
• Tru-Vee Openers/Disc Blades
  • Measure point of blade contact -Make sure they meet manufacturers specification
  • Diameter of blades- Check manufacturers specification
  • Bearings and scrapers
• Seed Tubes & Tube Guard
  • Seed tube-worn edges or broken
  • Seed tube guard- loose or broken rivets, width worn, too narrow
• Seed firmers
  • installed correctly, adjust tension, replace with weat
• Closing Wheel Assembly
  • Tires and wheel bearings
  • Centered over seed trench
  • Staggered wheel set up
  • Pivot assembly holes
• Insecticide Assembly
  • Box and feed roll condition
  • Hose attachment clean
  • Insecticide bander
• Seed Meters
  • Clean meters
  • Have meters calibrated

In-field adjustments: Is your planter running level?  Check the frame level & parallel linkage level.  Adjust hitch height.  Most important is to maintain a proper planter speed.  Reduce all planter bounce and vibrations.  Slow down! Check your row cleaners and make sure they are set at a correct depth.  Make sure your down pressure is properly set.

I apologize that this entry is a little behind the curve and many growers are in the middle of planting or just finishing up particularly in southwest Georgia but I felt it was important to get this information out to those that are just beginning.  I also encourage everyone to conduct an emergence test this year if you are just beginning to plant.  It is simple and can help you visualize your losses from delayed emerging plants.  Keep a close watch on your growing degree units as it takes an average of ~100 growing degree units for corn seed to emerge.  Once the first plant emerges in a given row length of your choosing (suggest several feet), mark the plant with a colored flag. An emerged plant should have the tip exposed about 1/8 inch above the soil service. Over the next 12 hours mark each plant that emerges with the same colored flag.  Repeat this process over the next 12 hours using a different colored flag for each time period.  You will likely use 3 to 6 different colored flags over the next three to four days.  Record how many plants are flagged by color.  Carefully observe these plants over the season.  Walk your fields observing your stand establishment.  At the end of the season and prior to harvest, take several buckets or bags and harvest each individual ear by color and combine them by color.  Repeat this process until you have all ears harvested and NOTE all those plants that did not have an ear.  Record the number of ears  for each colored flag (and plants that did not have a ear).  Shell all the ears by color, and weigh and record the data by color.  Take the yield, moisture, etc of each color and convert it to bushels per acre.  You will begin to see the importance of having an even plant emergence.  Also, you would have taken a great step towards knowing what may be limiting your yield.