Posts tagged ‘nitrogen fertilizer’

Corn Seeding Rates: To Increase or Not to Increase

A few seed companies have been discussing with farmers the idea of increasing their corn seeding rates in 2009 from 30,000-32,000 seeds/acre to nearly 40,000 seeds/acre with the idea that this increase in seeding rate will maximize potential corn yield. In 2008, a research trial was conducted at Farm Focus to look at this very issue. This one year trial examined corn yield differences at two different seeding rates, 30,000 and 40,000 seeds/A, as well at the influence of nitrogen and foliar fungicide.

In a head-to-head comparison of 30,000 seeds/acre and 40,000 seeds/acre with equivalent inputs and OSU recommended nitrogen rates, the 30,000 seeds/acre seeding rate showed a statistically significant yield advantage as well as nearly a $70/acre increase in net revenue based on OSU crop budgets. In the same study we also looked at a comparison of 30,000 seeds/acre and 40,000 seeds/acre with a higher than recommended rate of nitrogen, so as to rule out nitrogen as a limiting factor for the higher seeding rate. Again, the 30,000 seeds/acre corn seeding rate showed a statistically significant yield advantage over the 40,000 seeds/acre seeding rate. In this high nitrogen rate comparison, the economic benefit of using the lower seeding rate provided a net revenue increase of over $80/A compared to the higher seeding rate.

This study at Farm Focus does have a few limitations. First, the data is from one-year only. Second, the planting date was May 23 and a May planting date may not react to increasing corn seeding rate as much as an April planting date.

This research study is available in its’ entirety here:

Full podcast here:

EDIT 02/09/09

This study has generated a life of its’ own, and I need reinforce in this post some of the limitations of this study that are in the full reference above:

  • this data is from one year only
  • this corn study was planted May 23
  • this data comes from only one corn hybrid
  • budgets are based on generalized OSU crop budgets

    February 4, 2009 at 7:00 am

    Nitrogen Deficiencies in Corn — Easy to See Now

    Emerson Nafziger, Extension Agronomy Specialist for the University of Illinois, wrote an article on nitrogen deficiencies in corn. The article is very timely as many growers are now seeing the effect of nitrogen deficiency appear in their corn fields in NW Ohio. Unfortunately there isn’t much that can be done at this stage to assist the corn crop; Emerson writes:

    There is little to be done to correct N deficiency in corn following pollination, especially when we have to count on uncertain rainfall to move fertilizer N into the soil so the roots can take it up. Root systems are also starting to decline in size and activity once ears reach the roasting ear stage. It is unlikely that 10 lb or so of N applied using a foliar-safe form will do much to cure deficiency this late.

    Listen to my podcast on his article here:

    August 13, 2008 at 7:00 am


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