By ADAM SPELHAUG
There are a few factors to consider if you are thinking about increasing your corn population this year.
I’ve studied population the past six years in my “Ole & Sven” plots, and also for the past couple of years with our Plus20 farmers. With the increased use of planters with hydraulic drives, it is easier to plant population strips, versus stopping and changing drive sprockets. I’ve observed that you give up more potential by not having enough population in the field than having too many plants for the resources.
We produce about 5.5 bushels per 1,000 plants on every acre in our region. Increasing your planting rate by 2,000 plants could result in another 11 bushels per acre. At $5 per bushel, that equals a potential $55 per acre, for a $6 per acre ($237 per bag/80,000 x 2,000) investment in planting cost. If drought or flooding occur, yields would be lost regardless if you had 34,000 plants or 30,000 plants per acre.
The big thing to consider when upping your population is that the extra plants need to be fed. Increased nitrogen is a must, but phosphorus, potassium, sulfur and zinc also need to be considered. These may not have been limiting nutrients when you were planting 28,000 to 30,000 seeds per acre, but may show deficiencies with the higher population.
When pushing populations, make sure you know your hybrids and their characteristics. Most of the current hybrids on the market today have good stalk and root strength. However, there are some hybrids that have super-high yield potential, but do need to be managed or watched to maximize those yields. These types of hybrids will work in a high-population situation, but may need to be harvested in a timely manner. We learned lessons like this last year with the weekly high winds we received.
Stand placement is another important factor to consider when planting higher populations. Increasing populations will decrease the plant-to-plant spacing in the row. This is more of a concern in 30-inch rows where the spacing is tighter.
An ideal spacing for 32,000 plants is 6.56 inches, while planting 36,000 plants reduces that spacing to 5.83 inches, giving a smaller margin for error. Spacing for 22-inch rows will be about 2 inches more in the row. Corn does not like to compete for resources with its neighbors, so the more even the stand the better production you will receive from each plant. If the spacing is too tight, both plants will be reduced, leading to poor yields and underutilizing that higher population.
Raising your population is more than just adding additional kernels to the soil. Make sure you make a plan and adjust your resources to meet the needs of the additional plants.
This article published in the February, 2012 edition of DAKOTA FARMER.
All rights reserved. Copyright Farm Progress Cos. 2012.