NDSU Extension - Ramsey County


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March 29, 2010 - Ag Column


It sure is nice out and fun to talk to cattle producers that are not knee deep in mud, like last year.  I have not heard of health problems yet but I have heard of more birth problems this spring.  I have heard of more backward calves being born than any one time of my personal calving history.  We sure can be thankful for the wonderful spring and would appear MAYBE an early spring.  Just the other day we talked about normal and came to the conclusion that no one knows what normal is.  Is normal in the 80’s or the 90’s or maybe the 00’, we really do not know what normal is but hopefully we can get an early start and fly through springs work with no difficulties. 

I cleaned the NDawn station today and could not help but think of all of you that use the station.  This is a great asset to the farming and insurance industry.  I would continue to urge you to use the station and the information it provides.  It can be reached on line at http://ndawn.ndsu.nodak.edu/index.html or calling 701-398-3008.  At the conclusion of you phone call please conclude with pressing the star key on your phone.  This tells the station to stop responding to your requests.

It is that time of year to also take that one last look over seed supplies.  I know most of you have all of your seed in place but a quick look over inventory is always good.  Seed supplies are tight in most areas and don’t get your hopes up for getting the seed you are looking for, if you need extra.  I one of the big questions this year is “should I be planting wheat or barley”?  To answer that question a couple of questions need to be answered; do you need a rotation of a grass crop to reduce disease pressure from the heavy cropping of legumes and does the crop meet the needs of the cashflow statement.  Surprisingly there are producers that have a very nice price hedged for fall delivery of wheat and there are actually some wheat contracts already in place for fall of 2011.   At this point it seems mute to talk about prices because of the protein discounts however we might want to talk about strategies to raise protein in wheat and will do that next week as we do need to address grain storage issues.  This past winter left many challenges due to the extreme cold followed by very warm temperatures.  This change in climate really affects the allowable storage time of stored/wet grain.  In some cases has started the sprout process in what producers thought was malt barley.  Included in this ag column is a bulletin that Ken Hellevang published last fall and needs to be looked at again.

Malting Barley Requires Special Care When Drying


Malting barley germination will be lost if adequate airflow is not provided to barley being dried by natural air or low-temperature drying so that it is dried within the allowable storage time, according to Ken Hellevang, North Dakota State University Extension Service agricultural engineer and grain-drying expert.


Minimum recommended airflow rates and drying times to dry the barley within the allowable storage time are 1.25 cubic feet per minute per bushel (cfm/bu) to dry 18 percent moisture barley in about 20 days and 0.75 cfm/bu to dry up to 17 percent moisture barley in about 31 days, based on typical August weather conditions.


“Drying occurs in a zone that moves from the bottom of the bin to the top if the air is pushed up through the barley,” Hellevang says. “Grain at the top will stay near the initial moisture content until the drying zone reaches the top of the grain, so adequate airflow to dry the barley within its allowable storage time is critical.”


Use a fan selection program or table, such as one available from the NDSU Extension Service, to determine whether you have adequate airflow. For more information, go to NDSU’s grain drying, handling and storage Web site at http://www.ag.ndsu.nodak.edu/abeng/postharvest.htm. You also can have the fan supplier verify the airflow rate.


The allowable storage time (or drying time) is related to the grain temperature and moisture content. The allowable storage time based on germination is about 20 days for 18 percent moisture barley at 70 F, 30 days at 17 percent and 50 days at 16 percent. Germination will be lost before mold growth is visible.


Both the time required to complete drying and the allowable storage time will be longer at cooler temperatures because the cooler air holds less moisture. Drying grain at 60 degrees will take about 30 percent longer than it does at 70 degrees. Drying 17 percent moisture barley will take about 40 days with an airflow rate of 0.75 cfm/bu at 60 degrees, which is about 1.3 times longer than the 31 days at 70 degrees. The allowable storage time for 17 percent moisture barley is about 65 days at 60 degrees, or about twice as long as the 30 days at 70 degrees.


Adding supplemental heat to a natural-air drying system will reduce the moisture content of the grain but only reduces the drying time slightly. Warming the air by 5 degrees will reduce the relative humidity by about 10 percent and the barley moisture content by about 1.5 percentage points. The air normally will be warmed 3 to 5 degrees by the fan operating at a static pressure of about 5 to 6 inches associated with drying barley, so, typically, little additional heat is needed.


Adding more heat than is required results in the barley being dried to a moisture content lower than desired. The equilibrium moisture content for barley is about 12 percent at 70 F and 60 percent relative humidity, which are average conditions for August. September air conditions of 58 F and 70 percent relative humidity will be 63 F and 60 percent relative humidity if the fan heats the air 5 degrees. This air will dry barley to about 12 percent moisture content.


Hellevang also recommends limiting the plenum temperature in a high-temperature dryer to a maximum of 110 F when drying malting barley to maintain germination.







http://www.ag.ndsu.edu/news/newsreleases/2009/oct-12-2009/cool-stored-wheat-and-barley-check-moisture- content/


Cool Stored Wheat and Barley, Check Moisture Content Stored wheat and barley should be cooled and checked for moisture content to prevent deterioration.


The warm September temperatures may have helped with the grain harvest, but they also might have created conditions that can cause stored grain to deteriorate, North Dakota State University’s grain drying expert warns.


The optimum temperature for insect infestations and mold growth is about 80 degrees, according to Ken Hellevang, NDSU Extension Service agricultural engineer.


Insect reproduction is slowed at temperatures below about 70 degrees and insects are dormant below about 50 degrees.


The allowable storage time without mold growth is approximately doubled for each 10 degrees the grain is cooled. For example, the allowable storage time for 16 percent moisture content wheat is about 70 days at 70 degrees, about 120 days at 60 degrees and about 230 days at 50 degrees. The allowable storage time for 14 percent moisture malting barley, based on germination, is about 70 days at 80 degrees, 175 days at 70 degrees and 430 days at 60 degrees.


Producers need to remember that grain moisture content will increase near the top center of the grain due to moisture migration if the grain is about 20 degrees warmer than the average outdoor temperature, Hellevang says.


Stored grain should be cooled to the average outdoor temperature during the fall using aeration. Cooling time can be estimated by dividing 15 by the airflow rate. For example, about 75 hours of fan time is required to cool the grain using an airflow rate of 0.2 cubic feet per minute per bushel. Grain temperature eventually should be cooled to about 25 degrees for winter storage.


Hellevang recommends producers measure the grain moisture content to check the status of drying and to develop a storage plan. However, moisture meters normally are not accurate for grain temperatures below about 40 degrees. To obtain an accurate value, producers should warm the grain sample in a sealed plastic bag or other sealed container to room temperature before measuring the moisture content.


A drying zone that is a couple of feet thick moves from the bottom of the bin to the top during natural air drying. If the top is not dry, collect samples from other levels to determine the progress of the drying front.


Warming the air by about 5 degrees will permit producers to continue to dry wheat during October using a natural-air, low-temperature (NA/LT) drying system if the outdoor air temperature average is above 40 degrees. The moisture-holding capacity of the air at temperatures below about 40 degrees is small, so drying becomes inefficient using NA/LT drying. Adding more heat causes grain in the bottom of the bin to be dried to a moisture content lower than desired and changes the drying speed very little.


Drying speed primarily is dependent on the airflow rate. An airflow rate of 0.75 cubic feet per minute per bushel (cfm/bu) will dry wheat at moisture contents up to 17 percent. However, drying time will be about twice as long at 50 degrees as at 70 degrees. Drying can be completed in late April and May using natural air drying if the moisture content is 17 percent or less.


Use a bin-stirring device or do batch-in-bin drying with only a few feet of grain in the bin if the air is heated more than 5 to 10 degrees. If using a high-temperature dryer, limit the plenum temperature to prevent damaging the grain.


Dryer temperature will vary with dryer type, but a general recommended maximum air temperature for drying milling wheat in a continuous-flow dryer is 150 F for 16 percent moisture content and 130 F for 20 percent moisture content wheat. Hellevang also recommends limiting the plenum temperature in a high-temperature dryer to a maximum of 110 F when drying malting barley to maintain germination.


 http://www.ag.ndsu.edu/news/newsreleases/2010/march-8-2010/wet-stored-grain-will-deteriorate-rapidly-in- spring/


Wet Stored Grain Will Deteriorate Rapidly in Spring

Moisture content, temperature and quality will affect stored grain.


The storability of grain depends on grain quality, moisture content and temperature.


Grain moisture content must decrease as grain temperature increases to store grain safely, says Ken Hellevang, North Dakota State University Extension Service grain drying expert.


The allowable storage time for 22 percent moisture corn is about 190 days at 30 degrees, 60 days at 40 degrees and only 30 days at 50 degrees. Therefore, as stored grain temperature increases, the grain moisture content must decrease for safe storage. The allowable storage time for 18 percent moisture corn at 50 degrees is 90 days.


Stored grain temperature increases in the spring due to outdoor temperatures increasing and solar heat gain on the bin. Solar energy produces more than twice as much heat on the south wall of a bin in early spring than during the summer. This causes grain temperature to increase rapidly in the spring.


Immature grain and grain with damage to the seed coat is more prone to storage problems, so the grain should be stored at a lower moisture content than normal, Hellevang says. Also, stored grain should be monitored more closely to detect any storage problems early. Grain temperature and moisture content should be checked every two weeks during the spring and summer. Grain should be examined for insect infestations as well.


Corn needs to be dried to 13 percent moisture for summer storage to prevent spoilage. Soybeans should be dried to 11 percent, wheat to 13 percent, barley to 12 percent and oil sunflowers to 8 percent for summer storage.


Grain should be kept cool during spring and summer storage. Periodically run aeration fans to keep the grain temperature below 40 degrees during the spring.


When checking the moisture content of stored grain, verify that the moisture content measured by the meter has been adjusted for grain temperature. In addition, remember that moisture measurements of grain at temperatures below about 40 degrees are not accurate, Hellevang says.


Verify the accuracy of the measurement by warming the grain sample to room temperature in a sealed plastic bag before measuring the moisture content.


Hellevang says another problem is that grain storage molds will grow and grain spoilage will occur in grain bags unless the grain is dry. Grain in the bags will be at average outdoor temperatures, so grain will deteriorate rapidly as outdoor temperatures increase unless it is at recommended summer storage moisture contents.


Corn at moisture contents exceeding 20 percent should be dried in a high-temperature dryer because of the potential for corn field molds to continue to grow at moisture contents exceeding about 20 percent when grain temperature increases above about 40 degrees.


For natural air drying, assure that the airflow rate supplied by the fan is at least 1 cubic foot per minute per bushel (cfm/bu) and the initial corn moisture does not exceed 20 percent. Start drying when the outside air temperature averages about 40 degrees. Below that temperature, the moisture-holding capacity of the air is so small that very little drying occurs.


An airflow rate of at least 1 cfm/bu is recommended to naturally air dry up to 16 percent moisture soybeans. The expected drying time with this airflow rate will be about 50 days. The allowable storage time for 18 percent moisture soybeans is only about 40 days at 50 degrees, so a minimum airflow rate of 1.5 cfm/bu is recommended to naturally air dry 18 percent moisture soybeans.


For more information, visit NDSU’s grain drying, handling and storage Web site at http://'www.ag.ndsu.nodak.edu/abeng/postharvest.htm.


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