RESIDUAL SOIL NITROGEN
The following article is from the National Sunflower Association. With fertilizer and fuel prices as high as they are, it provides some good information for people to keep in mind.
With fertilizer prices that have risen significantly since last fall, one solution might be to plant sunflower, which uses nitrogen left behind by other crops.
On-farm observations and university research validate the sunflower plant’s ability to nab soil N too deep to be used by other crops. A study at the USDA-ARS Central Great Plains Research Station in Akron, Colo., in the late 1990s analyzed recovery of N fertilizer placed deep in the soil profile with different placement methods. The Akron researchers found that sunflower recovered half the fertilizer N placed two feet deep. They measured 23% recovery from fertilizer N placed four feet deep, and 12% recovery at five and a half feet deep.
Drought can result in high amounts of residual N left behind in a non-leaching environment. For example, North Dakota State University Extension soil fertility specialist David Franzen recalls a nutrient analysis several years ago in a field near Williston, N.D., where N levels from 2-4 feet were over 200 lb/ac. Thus, last year’s drought in many areas of the Plains means there may be a significant amount of residual soil N that would be readily used by sunflower.
A lot of soil N can be left behind in irrigated environments as well. For example, on fields in the High Plains that have been planted to irrigated corn over multiple years, it can be common to find 200 to 400 lbs/ac of nitrate below the corn root zone, typically three or more feet deep in the soil.
As one of the deepest rooting crops grown, sunflower will root down and extract residual N, provided there’s not a compaction zone to inhibit root growth, and if subsoil moisture is adequate to encourage root growth. The only way to know for sure what nutrients your fields need (or don’t need) is through soil sampling analysis. Consider a deeper probe (beyond 2 ft) to get a better idea about N further down in the soil that might be there for sunflower’s taking.
“Weather will obviously have a big impact on planting intentions,” says Larry Kleingartner, executive director of the National Sunflower Association. “A heavy rain or late spring snow can derail plans to seed early season crops like wheat, field peas or canola, as well as crops with a narrow planting window, like corn. In those cases, sunflower is an excellent ‘Plan B’ crop, with a wide planting window and that ability to use residual soil nitrogen.”
2007 County Rents and Values
The 2007 edition of the North Dakota County Rents and Values is now available. This publication provides updated information on land values, as well as an average over the past 5 years. If you would like to take a look at a copy please stop by the office or give me a call.
NDAWN Update
As we get into spring, I thought I would take a minute to remind you about the services offered by the NDAWN weather station here in the county. By calling the station directly (872-3016) you can receive 10 minute weather variables including: Air temp, Relative Humidity, Rainfall, Wind speed and direction, and soil temp. By going online to http://ndawn.ndsu.nodak.edu you can see the previous data as well as growing degree days, crop disease forecasting, crop water use, as well as many other data sets. The weather station in Golden Valley County is sponsored by the Golden Valley Ag Improvement Association. For a copy of the quarterly data complied from across the state go to: www.soilsci.ndsu.nodak.edu/ndawn/Reports/winter07.pdf
Weed Guide Errors
As I mentioned last month there is a page in the 2007 ND Weed Guide that had been revised. The revised page (page 22) deals with Roundup ready corn. If you need a copy of the revision please let me know and I will get one to you. Also, I have been notified that in several copies of the book around the state pages 17-22 are missing completely. I have not found a book like this in Golden Valley County, but please check your books and let me know if you are missing pages.
Seed Treatment approved for Lentil
The U.S. Environmental Protection Agency has approved a specific Section 18 exemption for the fungicides LSP Flowable Fungicide and Mertect(r) 340-F Fungicide, allowing their use as a seed treatment to control Ascochyta blight in lentils. This exemption is allowing for a single direct application of the fungicides as a seed treatment by a processor. Manual seed treatment is not allowed and the exemption is only valid through June 1st. For complete rules and regulations on using these products to control Ascochyta in lentils contact the office or the exemption use directions can be downloaded from the Department Section 18 page at (www.agdepartment.com/Programs/Plant/Section18Exemptions.html) or the NDSU Pesticide Certification and Training page at (www.ag.ndsu.nodak.edu/aginfo/pesticid/pesticid.htm).
2007 WEED ID SEMINARS
The ND Weed Control Association has again organized ten weed ID seminars across the state. Presenters are Ken Eraas from the ND Department of Agriculture and Marge Rayda from APHIS. If you plan on attending could you please notify the local contacts listed below or Shauna Berg at 256-2229, smberg@nd.gov. These seminars are intended for anyone that wants to learn more about the noxious and invasive weeds in ND, including Federal, State, local or private land managers and crop advisors. The daily schedule for each location begins with 9:30 a.m. registration, from 10:00 a.m. until noon will be training, from noon until 1:00 p.m. lunch will be on your own, and from 1:00 until about 3:00 Ken will finish up the training.
The Date, Time and Locations nearest here are as follows:
Carson May 10th County 4-H Building Contact: Merlin Leithold 584-3204 leithold@westriv.com
Killdeer May 11th Buckskin Bar Contact: Diane Allmendinger 846-7374 diane.allmendinger@sendit.nodak.edu
New Publications
2007 County Rents & Values