Mid-County Messenger Page 3 www . midcountycoop . com Spring 2009
Potassium is a critical nutrient for dairy producers . Being one of the three macro nutrients that we regularly apply in the form of fertilizer to fields , potassium plays an integral role in a plants ability to regulate water and maintain stalk quality . Most of the potassium is stored in the leaf and stem components of the plant and little , by comparison is found in the grain ; thus the crop removal is relatively low for soybean and corn grain and relatively high for alfalfa , corn silage , or corn and bean straw .
Many dairy farmers know that alfalfa is copious user of potassium , but it also throws a curve ball by being a luxurious consumer of potassium . Think of an alfalfa plant going to the potassium all you can eat buffet , if there is potassium available for the plant , the plant will consume it whether it needs it or not .
Mid-County Agronomy Inoculation : The forgotten soybean bin buster !
Doug Kraska Ag Production Specialist ( 952 ) 466-3730 dougk @ midcountycoop . com
Joe Forner Agronomist ( 952 ) 466-3730 joef @ midcountycoop . com
Hannah Schneider Agronomy Intern
For a 50 bushel soybean crop around 225 pounds of nitrogen are required . About 35 % comes from the soil with the balance from nitrogen fixation . For nitrogen fixation to occur , the nitrogen
My name is Hannah Schneider . I am a sophomore at the University of Minnesota majoring in Applied Plant Science and Agricultural Education . I have always been interested in agriculture and grew up on a hobby farm just south of Cologne , Minnesota . fixing bacteria , known as Bradyrhizobia Japonicum must be established in the soil through seed inoculation .
When Rhizohia bacteria is present in the soil it attaches to the soybean root on new root hairs immediately behind the growing root tip . Within 10-14 days the bacteria will form a nodule . The wart like structure on the soybean root contains a Bradyrhizobia Japonicum colony that grows very rapidly and begins fixing nitrogen at the V2-V3 soybean growth stage .
Fertilization choices
There are two negative effects of this luxurious consumption . The most serious effect is occurrence of milk fever in freshening dairy cows . I think most dairy farmers have had some experience and from what I have gathered , they have adopted practices to mitigate milk fever by carefully watching the rations of their dry cows .
The second issue with excessive potassium uptake is that it may be in the form of commercial fertilizer . With potash prices as high as they are now , this excess fertilizer is in essence lost unless it is returned as manure . Once a cow is milking heavily , she can take in a higher potassium ration as she can excrete the excess in her milk . In essence , a portion of the excess potassium in the field will not end up back on the farm in the form of manure but leave the farm in the form of milk .
Another caveat of potassium is that the concentration of it in the soil is not constant year round . Typically in the spring , the concentration will be higher than late summer . Potassium is naturally released by mineral soils during the freeze and thaw of winter and is also more available to the plant in moist soils than in dry soils . As the growing season progresses ,
I plan on obtaining my undergraduate degree in Agricultural Education and Applied Plant Science in the spring of 2011 . My interest in agriculture has been shaped by many experiences . This past summer I had the privilege of working at Mid-County Coop as a summer agronomy intern . Working for Mid-County really opened my eyes to all the opportunities agriculture has to offer and really sparked my interest in agronomy . I really enjoyed learning more about agriculture and the knowledge I gained this past summer about weed identification and plant diseases has really been beneficial in many of my courses at the University of Minnesota .
Inoculants can be added as a liquid or a peat based powder to the seed . Some newer products have a PGPR ( plant growth promoting rhizobacteria ) that stimulate plant growth . Overtime soybean inoculants have produced over a $ 3 return for each $ 1 spent .
Bio-Boost Plus ( PGPR ) and N-Prove are liquid products and RhizoStick a peat base product are the inoculants we carry at Mid-County . With the purchase of liquid inoculants we have a treater program .
the crop removes a portion of this potassium dropping the concentration in the soil .
There is a wide variety of different theories regarding fertilizing alfalfa . Multiple small applications are widely regarded as being superior to a single large application . Applications made early in the spring before first cut have the least utility , since this is usually when the soil naturally has the highest potassium concentration . Adding fertilizer at this time will do little to increase first cut yield and will elevate the potassium concentration within the forage itself . Applying multiple small applications or spoon feeding potash after first , second , and third cut is the best way to manage potassium for maximum yield and highest quality feed value .
Soil testing and tissue testing are good tools to monitor potassium levels before the hay ever hits the chopper or baler . Using these test results , we can prescribe the right amount of crop nutrients to apply and when and how to apply them for the maximum benefit . With the economics of dairying today , it is imperative that we use all the tools available to us before we make these fertilization decisions .
Mid-County introduces new staff member
It is my career goal that I will be able to use technology , diplomacy , communication , and knowledge to work against hunger and for the development of a stronger , more sustainable agriculture industry . This goal could lead me in many directions and I look forward to the challenge of working in the great and ever-evolving field of agriculture . My greatest desire is to never stop in my pursuit of knowledge ; I want a career that advocates me to question , uncover answers , and truly learn everyday .