May 232012

Planting the Blank Slate on May 9th 2012


When you say the word “fertilizer” people who aren’t familiar with agriculture often think it means something dangerous or unnatural.  For that reason, I like to refer to fertilizer as what it really is: plant food.  On my farm, my long-term goal is to leave the land in better condition for the next generation than it was when I started farming.  This should be easy on the Blank Slate because the land was in terrible condition to begin with (erosion, low fertility, low organic matter, I’d better stop the list before I get too depressed).

One of the big things I’m trying to learn this year is the correlation between plant population (how many seeds per acre I plant) and plant fertility needs.  When I talk to other farmers about how much fertilizer to apply to their fields it all comes back to what kind of yield level they anticipate being at.  If you’re raising 200 bushel corn, the USDA estimates your crop will remove from the soil 180 pounds of nitrogen, 76 pounds of Phosphorus, and 60 pounds of Potassium, along with smaller amounts of all the other essential nutrients.  Those numbers are just for the nutrients that leave the field when you haul away the grain.  The crop actually needs to take in even more nutrients to grow a healthy root system and stalk that will stand until harvest and support and develop the ears of corn.

In my case, I applied fertility for a 170 bushel yield goal last year and raised only 150 bushels of corn (thanks to being blessed with two shots of hail in July).  Farmers never really have any idea of what yield will be other than guessing by previous history of that field and the knowledge of what management practices they intend to apply this year.  In year three of the Blank Slate project, I’m planning for 180 bushels per acre and will feed the crop accordingly.

THE EXPERIMENT – Please try this at home

1. I’m trying a couple different plant populations trying to learn what the optimum plant density per acre is for maximum yield on the Blank Slate.

2. With those plant populations I’m also trying to learn how to feed the crop just right.  If you don’t add more plant food when you add more plants, you end up with spindly little stalks that tend to fall over in the wind when there’s a great big ear of corn hanging 5 feet off the ground on each stalk.

3. I’m trying higher rates of nitrogen fertilizer on some of the plots to better evaluate my other nutrient applications.  I’ve experimented with higher rates of phosphorus, potassium, and micronutrients in the past.  High rates of those nutrients didn’t always help me much because I ran out of something else first.

Corn Emergence on Blank Slate May 16th

I’m really excited about the potential of this year’s crop.  I’m also working on getting my kids a little more involved this summer which should be interesting and fun.  Stay tuned.



Sorry, the comment form is closed at this time.

© 2011 Ag PhD - Information for Agriculture