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AgAlerts 2004 From Griggs County
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Issue # 5, June 4, 2004
Rolling fields can be done either PRE or POST emergence of soybeans. Advantages of rolling PRE emergence are low potential for crop injury but could result in soil-surface crusting or soil erosion. Rolling fields POST can cause plant injury including crushed leaves and cracked or broken stems. The growing point on a soybean plant is above the cotyledon leaves. If a plant is broken below the cotyledon leaves the plant will die. Injured plants may be more susceptible to lodging or disease. To best avoid too much injury, roll soybeans between the cotyledon stage and first trifoliate stage. Also, rolling during the warmest part of the day on less turgid plants will lessen injury.
Resent heavy rains has produced a lot of standing water.
How long can a crop survive in flooded conditions is environmentally dependant.
Under cool cloudy conditions, soybeans: about 3 days, drybeans: about 1 day, and
corn: 2 to 3 days. Under sunny and warm conditions, soybeans: 1.5 days, drybeans:
½ day, and corn 1 to 1.5 days. As temperature and sunny conditions increase,
the amount of time decreases.
Soybeans become nitrogen deficient and also susceptible to
iron chlorosis under flooded conditions. Phytophthora root rot in susceptible
varieties is frequently associated with flooding damage. Flooding causes
anarobic conditions (lack of oxygen) which will cause root damage. As flood
waters subside, plants may start to appear normal but will be stunted and yield
losses may occur.
The recent rains have caused major flooding in some areas
in eastern North Dakota. I was curious how many gallons of water did we receive?
Doing the math, a one inch rain will yield the following:
27,150 gallons water per acre
4,344,000 gallons per quarter
17,376,000 gallons per section
625,536,000 gallons per township
Now lets look at a five inch rain:
135,750 gallons per acre
21,720,000 gallons per quarter
86,8800,000 gallons per section
3,127,680,000 gallons per township
This web site is up and running for 2004. This site This web site provides information on risk of tan spot, Septoria blotch, leaf rust and Fusarium head blight (FHB = scab) for the 50 ND, 9 MN and 1 SD NDAWN locations. Once you access this site, there are directions how to use the forecasting models. You can access this site at the following web site:
http://www.ag.ndsu.nodak.edu/cropdisease/cropdisease.htm
Toll free phone information also is available at 1-888-248-7382 or (231-6601 in Fargo calling area). Dr. Shaukat Ali of the NDSU Plant Pathology Department will be maintaining this site.
Please Contact Our Office For Additional Information
E-mail: john.swenson@ndsu.edu
Go to the 2003 AgAlert Index Page