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What’s a fellow to do?

Woody Lane, Ph.D. for Progressive Forage Published on 30 March 2017
Variety traits, what they are and what they aren't

Let’s say I’m interested in renovating some pastures in western Oregon for intensive grazing. I want to plant appropriate forage varieties, so I need good information about their characteristics and yields. Where can I go?

First, I obtain some recommendations from traditional expert resources, like NRCS and the extension service, and possibly a few seed salesmen. I visit with neighbors about their experiences, and since we live in an internet world, I use Google and scan some websites.

I do locate the results of some yield trials, but to my dismay, I find that most were conducted in Arkansas or Holland or New South Wales – all different climates than mine. Also, the yields in those trials were obtained from cutting regimes that are completely different from my grazing system.

And finally, the local experts are recommending varieties that were originally released more than 15 years ago. What’s a fellow to do?

The problem isn’t the lack of choices of modern forages. The problem is the lack of good information to make those choices. Read on.

Once seed companies develop new forage varieties, they contract with organizations (usually agricultural universities) to conduct comparative yield tests called “plot trials.” Typically, these trials evaluate dozens of varieties, with forage plots planted in a grid pattern.

These plots are fertilized according to the soil test, usually with lots of nitrogen. Forage yields are measured at various intervals during the growing season, and the published results include total yields, interval yields, rankings, etc. Generally, these test plots are replicated (duplicated) on two or more sites to allow a valid statistical analysis of the data.

For a grazier, there are a few major drawbacks to this system: primarily protocol and location.

Since the standard testing protocol treats all forages as hay crops, it doesn’t evaluate varieties well for their genetic strengths under grazing management. For example, when all the varieties are planted at the same time and harvested at the same times, this means the intervals between cuttings are the same for all varieties.

This standardization allows for efficient labor management, but it masks differences in critical grazing traits, such as very early growth or speed of regrowth.

Plot trials usually standardize cutting intervals at 30-plus days. This is intriguing to graziers who may follow grazing strategies that treat faster-regrowth forages differently than slower-regrowth forages. Graziers may put animals on forages at intervals that range from 15 to 60 days, depending on forage growth rates.

Graziers are more flexible than hay-based protocols. They recognize a 30-day interval in May is agronomically very different from a 30-day interval in August.

Standard protocols also require that all trial plots receive fertilizer at the same time, regardless of an individual variety’s stage of regrowth. Since all plots are cut at the same time, this system may favor plants with higher growing points or plants that thrive under long rest periods. And mechanical harvests do not duplicate the trampling stress plants experience in a grazing situation.

Location is the other main drawback. I live west of the Cascade Mountains in a wet, Mediterranean climate: cool wet winters and hot dry summers, with 35 inches of rain falling mainly between October and June. Our growing season begins in autumn and lasts into late spring.

Summers are very dry. There is no summer forage growth without irrigation, but irrigated fields can grow forages 365 days per year. Here’s my quandary: How do the results of a plot trial under a hay-management protocol in Ohio or Minnesota – areas with hard winters and wet summers – apply to my intensive grazing situation in the wet Pacific Northwest? How can I use those plot data to guide my choice of forages for my conditions?

Simple: I can’t. At least not with any confidence.

For example, if variety XYZ tops a hay yield trial somewhere else across the country, does that mean anything to me as a grazier in Oregon? Conversely, if a variety that I know does well in my area shows up only in the middle of those rankings, should I jettison that variety from my future considerations?

To complicate the issue, plot trials are expensive, and fewer and fewer universities seem willing to conduct them frequently. Yet over the past 15 years, forage companies have released an increasing number of improved varieties and species, and this rate is increasing. Research in plant breeding takes a long time.

Companies releasing new forages this year initiated research on those varieties eight to 15 years ago. Hmmm … I believe we have a disconnect here.

Our country’s administrative structure for testing new commercial varieties is (how should I say it …) lacking, especially for grazing systems now followed by many farms and ranches. Important grazing traits, like fast regrowth, early response to rains, winter growth, etc., are not measured properly with the standard three-cut or four-cut yield trials.

Our universities can’t keep up with new varieties and species, plot trials don’t measure traits important to graziers and our advisory services that rely on those plot trials are providing recommendations that may be years behind the new releases.

The seed companies are frustrated because their new products are ignored, and graziers are frustrated because they can’t find current information that fits their operations.

We need something better. But who can do credible trial work? And where? Seed companies really can’t conduct plot trials in their own shops. That’s the classic “umpire” conundrum of a father umpiring his child’s Little League baseball game.

His judgement is always suspect. If he rules against his child’s team, he’ll be accused of harshness; if he rules in favor of his child’s team, he’ll be accused of favoritism. Either way, it’s a lose-lose situation.

But private industry can indeed do something. Companies could cooperate among themselves, with university input, to create an independent, impartial testing organization. This industry-accepted referee agency could conduct simple plot trials in the various climatic regions of the country, quickly and efficiently.

It would develop standard protocols for evaluating forages on the traits for which they were designed, not just in a cookie-cutter regimen for maximizing hay yields. We shouldn’t try to evaluate a quarter horse by running it in a steeplechase race. The quarter horse would not do well, but what does that prove?

In terms of protocol, here’s a potential starting point: Each variety in a plot trial should be managed to the strengths of that variety, which means plots may be harvested and possibly fertilized differently from each other or at different times.

For grazing data, each plot should be harvested when its total yield reaches something like 2,500 to 3,000 pounds per acre, whenever that occurs, as often as necessary, leaving a residual of a standardized 1,000 pounds per acre.

The amount and timing of nitrogen should be adjusted for the capabilities of the species and variety. The main measurement should be dry matter yield. That is the primary interest of any grazier.

Any other measurements – nutritional value, mineral content, nonstructural carbohydrates (primarily sugars, used by some for palatability rankings), tillering characteristics, etc. – can be piggybacked onto the basic protocol if the funds were available.

Sure, there are complexities with this strategy, and additional costs. Designing valid growth trials and summarizing the results would be challenging, and administrating the labor could be a nightmare, but compared to what? Compared to graziers who must use current unsuitable trial results and make important financial decisions on forage varieties without good information?

We can do better.  end mark

PHOTO: Variety trials – how useful are they? Should we be basing production decisions on them? Let’s have a frank discussion on what they are and what they aren’t. Photo by Lynn Jaynes.

Woody Lane is a certified forage and grassland professional with AFGC and teaches forage/grazing courses in Oregon, with an affiliate appointment with the crop and soil science department at Oregon State.

His book, From The Feed Trough: Essays and Insights on Livestock Nutrition in a Complex World, is available through Woody Lane.

Woody Lane, Ph.D.
  • Woody Lane, Ph.D.

  • Certified Forage and Grassland Professional
  • American Forage and Grassland Council