DelawarE Nutrient Management Notes

Soil and Litter Sampling for Nutrient Analyses

WHY SHOULD SOIL AND LITTER SAMPLES BE TAKEN?

· Soil sampling is the best way to determine the ability of a soil to supply nutrients to a growing crop. Applying nutrients without using a soil test to decide how much nutrient to apply, could result in yield reductions from lack of adequate nutrient or could result in applying nutrients when they are not needed. The application of nutrients to fields that do not need them will result not only in a loss in profitability from wasted dollars spent on nutrients but also these extra nutrients can potentially move from these fields into nearby water supplies causing environmental concerns.
· By monitoring the nutrient content of litter over time, you can use this information to predict the nutrient content of litter based on management practices. The nutrient content of poultry litter can vary greatly based on the management practices used at a farm. Therefore, it is important to keep records of the typical nutrient content of litter on a farm so that appropriate rates of litter can be applied to meet the nutrient demands of the crops to be grown.
· The composition of total cleanout litter differs from that of the cake and should be analyzed separately. Also, any change in your management program such as the number of flocks between cleanout, type of bird grown (i.e., cornish, broiler, roaster), litter treatment and the poultry company you grow for can have an influence on litter composition.

WHEN SHOULD SOIL AND LITTER SAMPLES BE TAKEN?

· Soil samples should be taken at least three months prior to planting the crop to allow time for sample analyses and time to apply any needed nutrients or lime. Sampling in the fall is usually best for crops that will be planted the next spring, because this allows ample time for analyses and planning. Every time that soil samples are taken, it is helpful to take them at nearly the same time of year because soil nutrient levels due fluctuate slightly depending on the time of the year.
· Litter samples should be taken as close to the application date as feasible. Adequate time should be allowed for the analyses, cleanout, spreader calibration and field application.

HOW SHOULD SOIL SAMPLES BE TAKEN?

· Each soil sample that is submitted for analysis should consist of 15 cores that have been taken from the field or area of sampling. It is recommended that each soil sample should represent an area that is no larger than 20 acres. For example, a field that is 40 acres in size would be divided into two 20-acre areas and one sample would be taken from each of these two areas. Therefore, a separate set of 15 cores would be taken from each of the two areas. Each set of 15 cores should be combined together, mixed, and then take a subsample to represent the individual sample to send to the laboratory for analyses.
· The proper depth of sampling is the surface 8-inch layer of soil for field crops and the surface 4-inch layer of soil for hay or pasture fields.

HOW SHOULD LITTER SAMPLES BE TAKEN?

· When sampling in the poultry house, take about 15 cores with a probe or shovel from random locations throughout the house making sure you sample the full depth of the litter and avoid the dirt floor. When sampling a stockpile, take about 10 scoops from the pile making sure that you penetrate as deep as possible into the pile. Do NOT include the wet, crusted outside layer of the pile in your sample.
· Place all 10 to 15 scoops or cores into a bucket and mix them thoroughly and then take a subsample and place in a one-gallon ziplock bag and seal. Leave space in the ziplock bag for gas expansion. Keep samples cool until delivery to the laboratory.

WHERE CAN I GET SOIL AND/OR LITTER SAMPLES ANALYZED?

· There are many choices for laboratories that can analyze soil samples and litter samples. Check with your local extension office, crop consultant, or fertilizer supplier for choices on laboratories.
· Using the same laboratory each year is advisable because one of the greatest values of soil testing or litter testing is to monitor changes in nutrient levels over time. This will allow you to see if your management practices are increasing, decreasing, or maintaining your nutrient levels. You can make changes to your management practices if your soil test levels are not meeting your long-term goals.
· By monitoring the nutrient content of litter over time, you can begin to predict the nutrient content of the litter based on your management practices.

WHO TO CONTACT FOR SOIL SAMPLING FOR MY NUTRIENT MANAGEMENT PLAN?

· Soil sampling is one of the main elements of a nutrient management plan. A Delaware nutrient management plan must be written by a certified nutrient management consultant. There are many certified nutrient management planners in Delaware in both the private and public sector. Please contact a private consultant, your local fertilizer dealer, or your local conservation district for information on how to obtain a nutrient management plan and to get details on soil sampling for this plan. To verify the certification of a nutrient management consultant, please contact the Nutrient Management Program within the Delaware Department of Agriculture at 800-282-8685 in Delaware, and 302-739-4811 for those outside of Delaware.
· Interpretation of the soil and litter analytical results will be provided by the certified nutrient management planner who writes the nutrient management plan.

Prepared by Greg Binford and Bud Malone, UD Cooperative Extension and the DNMC

Cooperative Extension Education in Agriculture and Home Economics, University of Delaware, Delaware State University and the United States Department of Agriculture cooperating. John C. Nye, Dean and Director. Distributed in furtherance of Acts of Congress of May 8 and June 30, 1914. It is the policy of the Delaware Cooperative Extension System that no persons shall be subjected to discrimination on the grounds of race, color, sex, disability, age, or national origin.

Last Updated: Monday, 19-Mar-2007 09:37:33 EDT