Forage Sampling, Submissions, Pricing

The Soil, Water and Plant Testing Laboratory offers analytical testing and science-based recommendations to help clients make informed resource management decisions. Services include comprehensive testing of soil, water, plant tissue, manure, compost, and other agricultural materials. These fee-based services are available to homeowners, agricultural producers, landscape professionals, consultants, government agencies, and University faculty and staff.

Sampling Instructions

Forage testing provides information about the nutritive value of forage. The information can be used to adjust the amount and composition of nutritional supplements offered to livestock consuming forage.

Proper sampling of forage is essential to obtain an accurate nutrient or mineral composition, dry matter content, or value of any feedstuff. Correct sampling and analysis is even more important under conditions that might increase feedstuff variability, such as challenging growing conditions.

Forage may be sampled in the pasture, after harvest and baling, or pre- and post-ensilage. All forage and feed samples should be stored in a freezer until shipping for analysis. To minimize the chances for mold formation or spoilage during shipping, ensure your samples arrive at the laboratory as quickly as possible.

Read Feed and Forage Sampling Instructions

Tools

  1. Core sampling probe: hand or power operated. A forage probe connected to a drill makes quick work of bale sampling, minimizes leaf loss, and reaches the bale’s interior for a more composite and representative sample. Forage probes can be purchased online or from farm supply stores or borrowed from most CSU Extension offices. The best samples are obtained using a core sampling probe.
  2. Clean bucket. The bucket is used to collect the individual samples collected from the hay bales.
  3. Cloth or plastic bag (gallon Ziplock).
  4. Permanent marker
Power drill with coring attachment
Hand crank coring device for core collection

Forage should be sample as near to the time of feeding or sales as possible. Sample processing takes from 5 to 7 business days depending on the tests requested, the methods used, and the overall number of samples received.

Hay quality depends on forage species, stage of maturity, cutting schedule, soil type, soil fertility, presence of weeds, harvest conditions, storage conditions, etc. When sampling, make sure all samples are taken from the same “Lot”. A “Lot” refers to a field of the same or mixed forage species, cutting time, stage of maturity, etc.

Quartering a Sample

Quartering is used to reduce a sample to a smaller, more manageable size in an unbiased manner. Prior to quartering, forage samples collected by hand must be cut into 2- to 3-inch pieces with shears or scissors and thoroughly mixed. Care must be taken to prevent leaf loss. Cored samples can be mixed as is. Pour the entire sample evenly into a pile on a clean surface, preferably paper, plastic, etc. Level the pile and divide into equal quarters (see diagram). Select and save two opposite quarters including the fines. If the sample is still too large, repeat the entire quartering procedure until the proper sample size is obtained and fit in the bag. Always use the quartering method when reducing sample size to obtain a representative sample for analysis.

Sample Collection

Small Square Bales

  1. Select a minimum of 20 random bales for coring. Collect a core (12 to 18 inches long) using a hay probe from each bale by probing into one end of the bale at a right angle to the surface.
  2. To hand sample, reach inside each bale and remove a handful of forage. Cut the sample into 2 to 3 inches pieces. Combine all 20 sample in a clean backet and mix thoroughly.

Large Square Bales

  1. Select a minimum of 20 random bales. Collect two cores (12 to 18 inches long) from each bale, one from each end, by probing at right angles to the surface.
  2. To hand sample, reach inside each bale and remove two or three handfuls from different locations. Take care not to lose leaves. Combine the grab samples in a bucket after cutting them into 2- to 3-inch pieces and mix well.

Large Round Bales

  1. Select a minimum of 20 random bales and collect two cores (12 to 18 inches long) from the circumference of each bale. Combine the cores in a bucket and mix well.
  2. To hand sample, reach inside each bale and remove two or three handfuls from different locations. Take care not to lose leaves. Combine the samples in a bucket after cutting them into 2- to 3-inch pieces and mix well.

Sampling Standing Forage

Standing forage is sometimes tested to determine if it is worth cutting for hay or to determine if grazing animals require supplemental feed. Select at least eight random locations within a field and clip the forage at grazing or harvest height from a one square foot area at each location. In grazing situations try and select the species being selectively grazed. Cut the samples into 2- to 3-inch pieces, combine in a bucket, and mix well. Spread the sample on paper and allow it to air-dry for two to three days. Molding may occur if wet samples are mailed.

Sampling Forage for nitrate

Select bales from hay that is suspected of containing excessive nitrate. Sample the bales using coring procedures outlined previously.

When sampling fields, clip at least 20 random plants at grazing height from the suspected area. Cut into 2- to 3-inch pieces, combine, and mix well in a bucket.

Silage Sampling

Silage samples can be collected from the face of a bunker silo as it is being fed and from the unloader of an upright silo. Bagged silage can be sampled by cutting small slits along the side of the bag and penetrating the hay sampler to collect the material.

Fresh Cut

Sample when moisture content of forage going into the silo is in the range of 64% to 72%. The test results of fresh samples will be similar to those samples after fermentation. Collect two to three gallons of silage from different sections of a load, combine, and mix thoroughly. Save about a quart. Refrigerate or freeze the samples until all loads are sampled. Combine samples, mix thoroughly all load samples, and collect a quart. The final sample should be placed in a cloth forage sample bag and then into a plastic bag to prevent moisture loss during shipping. Freeze the sample prior to mailing and mail samples early in the week to avoid weekend delays and reduce chances of molding.

Upright Silos

If a silo unloader is used, catch at least 12 handfuls of silage as it is discharged from the silo. Do not sample the top or bottom 2 to 3 feet in order to avoid unrepresentative, moldy, or otherwise damaged silage. Place the silage in a clean plastic, mix thoroughly, and reduce the sample size to approximately one quart using the quartering method described above. Place the sample in a forage bag and mail as described for fresh cut samples. If an unloader is not used, the same type of hand grab technique can be used from the silage thrown down for feeding. Silage in the silo can only be sampled to the depths one can reach. The sample only represents that portion of silage. Other parts of the silo may have silage of different quality.

Horizontal Silos

Collect samples using the hand method. Take samples from different areas across the entire surface of the open face of the silo. Combine samples, mix thoroughly, and quarter to reduce the size to about one quart.

Prepare Sample for shipping

Completely fill out the Feed and Forage submission form

Submit approximately ½ gallon of sample

Use a permanent marker to write sample ID or name and contact information on the sample bag. Please ensure that the information on the Forage Submission Form and sample bag are the same

When shipping samples, collect samples later in the afternoon and ship them the same day via overnight delivery

Seal the box with packing tape and mail or drop sample at:

Dropping or Mailing Address:

Soil Water and Plant Testing Lab
Terra Building T-316
4780 National Western Drive
Denver, CO 80216

Payment

Payment is expected at the time of sample(s) submission. With the exception of existing accounts, all other sample submissions must be accompanied with a check or money order made payable to Colorado State University for the total amount due.

For information about purchase orders or payment, contact the SWPTL at soiltestinglab@colostate.edu or 970 491-5061.

Feed and Forage Analysis Price List

Test CodePrice per sampleDescription
F1$50.00Proximate Complete: Moisture, Dry Matter, Crude Protein, Crude Fiber (CF), Acid Detergent Fiber (ADF), Neutral Detergent Fiber (NDF), Total Digestible Nutrients (TDN), Net Energy (gain, lactation, maintenance), Relative Feed Value (RFV)
F2$45.00Moisture, Dry Matter, Crude Protein, Crude Fiber (CF), Crude Fat (CFt), Acid Detergent Fiber (ADF), Neutral Detergent Fiber (NDF), Total Digestible Nutrients (TDN), Net Energy (gain, lactation, maintenance), Relative Feed Value (RFV), Lignin, Starch, Water Soluble Carbohydrates, Ethanol Soluble Carbohydrate, Non-fiber Carbohydrates, and Ash
F3$45.00Minerals: Moisture, Dry Matter, Phosphorus (P), Potassium (K), Calcium (Ca), Magnesium (Mg), Zinc (Zn), Iron (Fe), Manganese (Mn), Copper (Cu), and Molybdenum (Mo)
F4$35.00Nitrate (NO3)
F5$45.00Selenium (Se)

Frequently Asked Questions

What is forage testing?

Feed and forage testing is a laboratory analysis used to determine the nutritional value and quality of hay, silage, pasture, green chop, and other feed materials. Test results help producers make informed feeding and management decisions.

Why should I test my forage?

Forage quality can vary significantly depending on species, maturity, growing conditions, harvesting practices, and storage conditions. Testing helps ensure livestock receive balanced nutrition while avoiding unnecessary feed costs.

What types of forage can be tested?

We can analyze a variety of forage materials, including grass hay, legume hay, silage, green chop, pasture samples and mixed grass/legume forages.

How do I collect a forage sample?

Follow the collection instructions carefully (Forage Samples – Soil Testing Lab). Use a forage probe to collect cores from 20 randomly selected bales from the same lot. Combine the cores into a single composite sample and place them in a sealed plastic bag.

How should I collect a silage or fresh forage sample?

Follow the collection instructions carefully (Forage Samples – Soil Testing Lab). Collect several subsamples from different locations within the forage source and combine them into a composite sample. Seal the sample in a leak-proof bag and keep it refrigerated until shipment.

How much sample is required?

A minimum of ½ gallon of forage material is typically sufficient. For hay samples, submit a composite sample collected using a forage probe whenever possible.

How should samples be stored before shipping?

Samples should be kept cool and protected from direct sunlight. Refrigerate samples until they are ready to be mailed or delivered to the laboratory. For fresh forage and silage samples, include insulation and/or ice packs during shipping.

When should a sample be sent to the laboratory?

Samples should be sent as soon as possible after collection to maintain sample integrity and ensure accurate results.

How much does forage testing cost?

Costs vary depending on the tests requested. Visit our website for current pricing (Forage Samples – Soil Testing Lab)

What information should I include with my sample?

Please fill out the submittal form and provide:

Your name and contact information

Sample identification (Sample ID)

Sample Type (grass hay, alfalfa hay, corn silage, mixed grass/legume, grain)

Requested analyses (test code – F1, F4)

Any additional information relevant to the sample

How can I get my sample to the laboratory?

Samples may be mailed to the laboratory or dropped off in person during business hours (Monday through Friday 9 am to 4 pm). Please follow the sample submission instructions and include payment if mailing your sample.

How do I pay for feed and forage testing?

Payment is due when samples are submitted. Mailed samples must include a check or money order payable to Colorado State University for the total amount due. Samples dropped off in person can be paid for by Visa, Mastercard, or Discover credit/debit card. Purchase orders are accepted from city offices, landscape companies, crop and environmental consultants, schools, and universities.

How will my report be sent to me?

If an email address was provided with your sample submission, your feed and forage test report will be sent by email from Colorado State University quickbooks@notification.intuit.com. Be sure to check your spam or junk folder if you do not receive it. If no email address was provided, the report will be sent by regular USPS mail.

How long will it take to get my test results back?

Results will be available within 5 to 10 business days of sample receipt.

Can the laboratory provide feeding recommendations?

The laboratory provides analytical results. Producers should consult a nutritionist, extension specialist, or veterinarian for ration formulation and feeding recommendations.