When purchasing Timothy Hay commercially, appearance tells only part of the story.
Color, stem characteristics, leaf content, maturity and cleanliness are important, particularly in premium equestrian markets. However, importers, feed companies and livestock operations may also need measurable information about the nutritional characteristics of the forage.
Two terms commonly found on forage analysis reports are ADF and NDF.
Understanding what they represent can help buyers compare Timothy lots more intelligently.
What Is ADF in Timothy Hay?
ADF stands for Acid Detergent Fiber.
It represents a fiber fraction associated primarily with less digestible structural components of the plant.
In general, as a forage plant becomes more mature, its structural fiber tends to increase.
For commercial buyers, ADF can therefore provide useful information when evaluating forage maturity and expected digestibility.
It should not, however, be used as the only measure of Timothy quality.
What Is NDF in Timothy Hay?
NDF stands for Neutral Detergent Fiber.
It measures a broader portion of the plant’s structural fiber.
NDF is commonly considered when evaluating forage because fiber characteristics can influence how the forage functions within an overall feeding program.
As with ADF, the number should be interpreted together with other information rather than used as a standalone grade.
ADF vs. NDF: What Is the Difference?
The simplest commercial distinction is:
ADF is commonly associated with forage digestibility characteristics.
NDF is commonly associated with the overall structural fiber content of the forage and potential intake considerations.
Both provide information about the physical development and maturity of the crop.
For buyers comparing two Timothy lots, these measurements can reveal differences that may not be obvious from photographs alone.
How Maturity Affects Timothy Fiber
Timothy changes as the plant develops.
Earlier maturity generally produces a different balance of stem, leaf and fiber than later-maturity hay.
As the crop matures:
- Stem structure develops
- Structural fiber generally increases
- Leaf-to-stem balance can change
- Nutritional characteristics change
Harvest timing therefore plays an important role in determining the finished forage.
This is also why two Timothy lots from the same region can have different laboratory results.
Does Lower ADF or NDF Automatically Mean Better Timothy?
No.
“Better” depends on the intended use.
A premium equestrian distributor may value a particular combination of stem length, color, cleanliness and consistency.
A dairy operation may evaluate forage according to how it fits into a professionally formulated ration.
A commercial distributor may need to balance quality against landed cost.
A laboratory number should therefore help describe the forage—not replace an understanding of the customer’s application.
What Other Measurements Should Buyers Review?
A commercial forage analysis may include measurements such as:
Moisture
Important for forage condition, storage and international transportation.
Crude Protein
Provides information about the protein concentration of the tested sample.
RFV
Relative Feed Value is a calculated index commonly used as one reference point when comparing forage.
ADF
Provides information regarding a less digestible fiber fraction.
NDF
Provides information regarding the broader structural fiber fraction.
Depending on the laboratory and buyer requirements, additional measurements may also be available.
RFV, ADF and NDF Should Be Read Together
One mistake commercial buyers can make is focusing on a single number.
For example, asking only for RFV without reviewing the actual forage characteristics may provide an incomplete picture.
Similarly, buying solely according to protein can overlook maturity, stem characteristics, cleanliness and other important qualities.
A stronger purchasing decision considers:
Laboratory Analysis + Physical Crop Characteristics + Intended Use + Commercial Cost
Why Sample Results Can Vary
Hay is not manufactured in a controlled factory environment.
A field can contain natural variation, and sampling methodology affects laboratory results.
Results can differ depending on:
- Where samples are collected
- Number of bales sampled
- Field variation
- Cutting
- Maturity
- Weather
- Storage
- Laboratory methodology
For this reason, buyers should understand what a laboratory report represents and avoid assuming that a single sample perfectly describes every stem in an entire shipment.
ADF/NDF for Timothy Importers
For international importers, laboratory analysis can be particularly useful when establishing purchasing specifications.
A buyer may define acceptable ranges for:
- Moisture
- Crude protein
- ADF
- NDF
- RFV
and combine those requirements with physical specifications such as:
- Grade
- Cutting
- Color
- Stem characteristics
- Leaf content
- Cleanliness
- Bale format
This creates a more complete commercial specification.
Do All Timothy Grades Have Fixed ADF and NDF Values?
No.
Western Forage does not recommend assigning one guaranteed ADF or NDF number to every bale marketed under a particular grade.
Timothy is an agricultural crop, and laboratory characteristics vary by field, cutting, maturity and season.
Where analysis is available for a current lot, we can provide the applicable information for buyer review.
Buying Timothy Hay Based on Intended Use
When contacting Western Forage, buyers can provide their required nutritional ranges rather than simply requesting “the best Timothy.”
For example, tell us:
- Intended animal or customer segment
- Preferred grade
- Preferred cutting
- RFV requirement
- Moisture requirement
- Crude protein requirement
- ADF/NDF requirements
- Bale format
- Destination
- Monthly volume
Our team can then review current crop availability against those requirements.
Request Current Timothy Specifications
Western Forage supplies North American Timothy Hay to importers, distributors, equestrian businesses, livestock customers and feed companies.
Current specifications vary according to crop and lot.
For available Timothy, buyers can request current photographs, origin, cutting, grade, moisture information and available nutritional analysis.
Do not buy Timothy based on one number. Buy the crop that fits your market.
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