November Guelph Service Bulletin
We are more frequently receiving liquid greenhouse solution samples requesting our Nutrient Solution Complete package, when the sample is in fact a concentrated fertilizer. The Nutrient Solution package was designed to measure the levels of nutrient as it would be applied to a crop. Concentrated fertilizers, that will not be applied ‘as is’ to the crop, will be tested as Fertilizer. These samples require additional handling, such as multiple dilutions, special glassware, and different methods and instrument calibrations.
Any sample received with an Electrical Conductivity (EC) higher than 10.0 mmhos/cm, must be processed with fertilizer methods and pricing. We will reach out to contact customers directly, should any of these samples be received.
CORN SILAGE PROCESSING
Processing of corn silage has become a more common practice, which can improve fermentation by increasing the starches and sugars available to the silage microorganisms. This reduces dry matter losses in the silo and helps to break up cobs, improving fiber consumption.
Although kernel processing has improved over the past few years, it is still common to have very poorly processed corn. How well the kernel is processed is directly related to how well starch will digest in lactating dairy cows. Processing corn silage too fine will affect rumen health and lactation, therefore, it is necessary to quantitatively evaluate the effectiveness of a good processing.
A Corn Silage Processing Score test to evaluate kernel processing and determine the state of processing in stored corn silage is available at SGS. This test involves shaking silage over a series of sieves and measuring the percent of starch passing through a 4.75-mm sieve. Turn-around time for this test is 2 days and can be added to any of our packages.
Contact us for more information on these testing capabilities.
BUILDING SOIL FERTILITY
With current fertilizer prices, it may be an opportune time to build soil fertility. On average, many soils are declining in phosphorus and potassium. Soil testing determines the levels of extractable nutrients, provides a baseline of fertility trends over time, and allows for nutrient prescriptions to be made.
To increase soil test P by 1 ppm, it typically requires 35 lbs per acre of P205. For potassium, the amount is variable depending on soil texture, but 17 to 19 lbs K20 per acre is frequently cited.
Many growers ask where macronutrient levels should be maintained. A good rule of thumb is 20 ppm P and 120 ppm K; as higher levels have a lower likelihood of response from additional inputs for most rotational crops. For magnesium, maintaining levels approximately double that of potassium will eliminate the chance of K-induced magnesium deficiency.
For more information on these items, please contact: