What Is NTEP?

If you have ever compared two bags of grass seed and wondered whether one

cultivar is actually better than another, the National Turfgrass Evaluation

Program is one of the best places to look for evidence.

The National Turfgrass Evaluation Program, usually shortened to NTEP,

coordinates standardized turfgrass trials across the United States and Canada.

Cultivars and experimental breeding lines are planted at multiple research

locations and evaluated over multiple years. NTEP says its results are used by

plant breeders, researchers, extension specialists, government agencies, turf

professionals, growers, and consumers.

What does NTEP test?

NTEP trials can collect much more than a single measure of whether a grass

"looks good." Depending on the trial, researchers may evaluate characteristics

including turfgrass quality, color, density, establishment, disease resistance,

drought response, traffic tolerance, winter injury, and other stresses.

For PoaIndex, the central measurement is Turfgrass Quality because it is one

of the most consistently collected measurements across NTEP trials and

locations.

Why location matters

A cultivar that performs exceptionally well in one part of the country may not

perform the same way somewhere else.

That is not a flaw in NTEP data—it is one of the reasons the testing network

exists.

NTEP describes its trials as a way to understand both the broad adaptation of a

cultivar and whether it is suited to a local area or management level.

For example, a current Kentucky bluegrass report may contain results from

multiple Location Performance Index groups, regional summaries, maintenance

schedules, traffic studies, shade trials, and individual research locations.

That means there is rarely one universally correct answer to:

> What is the best Kentucky bluegrass?

A better question is:

> Which Kentucky bluegrass cultivars have performed well in relevant NTEP trials

> for conditions reasonably similar to mine?

That is the question PoaIndex is designed to help answer.

Why doesn't PoaIndex just use the national average?

National summaries are useful, but averaging everything together can hide

meaningful local differences.

PoaIndex therefore works from historical site-level NTEP Turfgrass Quality

evidence. A location entered by the user is used to identify geographically

relevant testing evidence, while longer-running regional sites provide

additional context.

This keeps the geographic information in the underlying NTEP data instead of

reducing every cultivar to a single national number.

NTEP does not sell grass seed

NTEP is a testing program, not a seed retailer.

Its trials may include named commercial cultivars as well as experimental

designations that breeders are still evaluating. Some experimental entries

later receive consumer-facing variety names; others may never be widely sold.

That distinction is important when reading NTEP reports.

PoaIndex separately uses reviewed identity information, including AOSCA records

where a match can be confirmed, to make experimental NTEP names more useful to

consumers. The AOSCA Grass Variety Review Board index includes both official

variety names and experimental designations for many reviewed grasses.

How PoaIndex uses NTEP

PoaIndex does not replace NTEP. It is an interpretation layer built around NTEP

evidence.

The goal is to make questions such as these easier to answer:

> What grass species make sense for my area?

> Which NTEP testing sites are relevant to me?

> Which cultivars have performed consistently at those sites?

> Is the evidence recent?

> Has the cultivar been connected to a recognizable commercial name?

Every recommendation should ultimately be traceable back to the evidence used

to produce it.

Next: How to Read NTEP Ratings

Sources

• NTEP overview
• NTEP ratings guidance
• Example Kentucky bluegrass quality report
• AOSCA Grass Index