Ramsey County Ag Column

By Bill Hodous

May 11, 2009

Howdy!!!!!

Well, another week of waiting.  We got tractors working almost all around us except to the northeast.  When you read this on Tuesday, we hopefully will  have our corn plot planted, west of Starkweather.  We staked the plot last Thursday and surprisingly the corn area was really good to the point the ground was rock hard.  I would like to thank John and Doug Erickstad for taking time to our corn plot area for us, we know we all have things to do and we really do appreciate the help.  I would also like to thank Chad and Curt Hofstad for their willingness to share their land with both Ramsey County and Towner County Crop Improvement associations.  This will be a great opportunity for area producers to learn opportunities that maybe did not exist for them before but could generate opportunities for all of us.  Keep an eye to the plot on Hwy 17, west of Starkweather or east of Cando.  We will have the plot well marked and well kept.  We will have full data, of all the entries entered into our plot, for a complete unbiased information.

I checked the NDawn station this morning and found bare soil temperature to be 46 degrees and turf soil temperatures to be 38 degrees.  Boy, do we need some warmer weather.  We could do all the planting we wanted but with temperatures this cool we will be waiting for germination like we did last year.  I talked to a producer, yesterday, and he said they started planting corn the day after Mother’s day last year. 

I have include a planting population chart for your consideration, in this spring’s planting.  I also found some good information provided by U of M that might generate some interest to you, also below.    

 Number of Plants Per Foot of Row

A.     Bauer - Mandan and J. Helm - Fargo

Each year questions arise about the correct seeding rate for hard red spring wheat. ‘Is a bushel and a peck enough?’ is a question I have been asked more than once.  Research in the mid nineties demonstrated that - on average - an initial stand of 30-32 plants/ft² maximized grain yield. As planting was delayed past the optimum, the initial stand needed to be increased by ~ 1 plant/ft² for each week of delay to maximize grain yield. With this number in mind and assuming a stand loss between 10-15% one can calculate a seeding rate using the following formula.

Repeated research, however, has demonstrated that the optimum seeding rates differ for individual varieties. To determine this optimum seeding rate the variety in question is tested at a wide range of seeding rates. The seeding rate for maximum grain yield can be derived from the parabolic response curve of grain yield versus number of plants per unit area, which increases quickly to a maximum and slowly decreases at higher plant densities.

The same research that yielded the current general recommendation actually tested 7, then commonly grown, wheat varieties. Some of the key findings were that:

1. The initial plant population increased as seeding rate increased, but the proportion of seedlings to live seed planted decreased with seeding rate, regardless of the planting date. This increase in stand loss was found for each planting date and year the trials were conducted. 
2. The stand loss that corresponded was, on average, 10% higher than the previously assumed 10-15% stand loss that is used in the seeding rate calculation.
3. The optimum seeding rate that maximizes grain yield varied between 29 and 37 plants/ft² when seeding early and 29 and 38 when planted late for individual varieties. 

Since none of the varieties tested at that time are grown anymore it is of little use to actually share all the results with you.

How should we then individualize the seeding rate recommendations for more modern varieties? First, repeating the optimum seeding rate trials is probably worthwhile. Meanwhile we may be able to approximate a recommendation – varieties that tillered well tended to have lower optimum plant densities when planted early, while varieties that didn’t tiller as much required higher plant densities both early and late planted. Thus if you’re growing some varieties that tiller well - such as Faller - you can probably be near the lower limits of the current recommendation while varieties that do not produce as many tillers - such as Granite - should probably be seeded at, if not beyond, the current upper limits of the recommendations.

524 4th Ave #5, 2nd Floor Ramsey County Courthouse
Devils Lake  ND  58301
701-662-7027
email - NDSU.Ramsey.Extension@ndsu.edu