Since its release by the University of Minnesota AES, Royal barley has proven its superiority as a companion and forage crop for the establishment of alfalfa. Developed as a feed and forage barley, its plant characteristics include lower fiber and lignin and higher protein content when compared to other barley cultivars.  Its mature height is the shortest of the barley varieties tested in the Midwest, however, when harvested in the late boot stage of plant development, its yield is not significantly different than other varieties.  Its short stature provides it with excellent lodging resistance and also creates less competition for under-seeded crops.  See tables 1 – 4 for yield and forage quality data.

Table 1.  Forage composition and forage yield of Robust and Royal at the soft dough stage of growth, grown at St. Paul, Crookston, and Stephan, MN in 1993.

Data table published in 1994 Minnesota Varietal Trials by the University of Minnesota AES.

Data taken from the 2004 Small Grain Varieties for Grain and Forage in Wisconsin (Varietal Trials).

Data taken from the 2005 Small Grain Varieties for Grain and Forage in Wisconsin (Varietal Trials).

Data taken from the 2007 Small Grain Varieties for Grain and Forage in Wisconsin (Varietal Trials).

Royal can be grown for feed grain production as well.  Although very little yield data exist, Royal can be expected to yield similarly to Robust barley.  It is important to note that Royal barley is not classified as a malting barley.  Grain quality is similar to other varieties, except that Royal has a blue aleurone, where many other varieties have a white aleurone.  Because of its short stature, even when harvested for grain, it is less competitive with an under-seeded crop than other cereal grains, however,  straw production may be less.

Why Royal Barley?

So,  Royal barley is significantly higher in feed quality.   Can’t higher forage yields and higher feed values be obtained by inter-planting peas with another barley variety, or even, planting peas with another cereal grain?  The short answer is yes.  However, this decision comes with a trade-off, and that trade-off is risk.  In this case, the risk is centered around the under-seeded alfalfa crop.

The decision to use a companion crop to establish alfalfa has many benefits over direct seeding:  Erosion control, weed suppression, an additional feed source, and increased field efficiency.  The choice of companion crops has a direct impact on the primary goal of establishing the alfalfa crop.  When selecting for higher volume, the risk is that the companion crop will negatively impact the alfalfa.

The Alternatives

During the late 1980’s, University of Wisconsin researchers did some extensive research with small grain – pea mixtures.  Table 5 below is a summary of that research and shows four different companion crop options:  Oats, Oats w/Peas, Barley, and Barley w/Peas.  The first thing to note is that, by planting peas with small grains, the protein levels are increased and fiber (NDF) is decreased.  This results in a higher value feed that is more digestible.

The second observation is that, with the addition of peas, the forage yield of the companion crop showed an increase, 7.5% with oat/pea mixtures, and 4.6% with barley/pea mixtures.  However, conversely, the alfalfa yield during the establishment year was decreased by 7.5% with oat/pea mixtures, and  11.4% with barley/pea mixtures.

Table 5 presents a summary of research conducted in 1986-1989 [L.B. Chapko, M.A. Brinkman, E.T. Gritten, and K.A. Albrecht, 1989].

Finally, it is observed that total forage yield (companion crop + alfalfa) for the seeding year was virtually unchanged.  No further information is available to identify whether or not there were negative impacts on alfalfa yields in the subsequent years following the seeding year.

To summarize, the more forage volume desired initially, the greater the impact on later alfalfa yields.  Keep in mind, this plot data cannot take into account the risks that face producers when dealing with whole fields spread across a wider geographical area.  As most producers have experienced, inopportune rain events can occur at about the time the companion crop should be harvested.  Herein lies the risk.

Alternative Risks

Risk is presented in two important ways.  The first is harvest timing.  It is critical with companion crops, and the optimum harvest window is generally very small, usually only a day, or two.  Every day past the optimum window, forage quality decreases and forage volume increases.  As time passes, the supply of poorer quality forage increases.

Second, as the companion crop advances towards maturity, it increasingly competes with the under-seeded alfalfa.  Eventually, especially with peas, the weight of the crop can result in severe lodging and can create a smothering effect.

A large volume of material takes longer to dry to the appropriate harvest moisture.  Many producers have windrowed high volume crops, only to see those windrows become exposed to rain while waiting for them to dry sufficiently, which, in turn, makes drying all the more difficult.  Unfortunately, a number of these producers have likely experienced a partial or total alfalfa stand reduction where the windrows laid prior to harvesting.

Risk Aversion

Although the data cannot be compared directly, in tables 2 through 4, Royal barley is shown to increase forage protein content to nearly the same level as that of the addition of peas with other barley varieties or oats (table 5), without the added cost of the peas.

While harvest timing affects every crop similarly, because of the short stature of Royal barley, the risk of lodging is greatly diminished.  This means that there is less competition and less risk for the under-seeded alfalfa.  In fact, it has been observed that alfalfa is often growing above the fully mature Royal barley.

Summary

The preceding information provides producers who are unfamiliar with Royal barley with an accurate description of how it has performed in comparison with varietal choices with which they may be more familiar.  While Royal barley may not provide the highest volume of forage when compared to the common alternatives above, the safety of the under-seeded alfalfa is much improved.  When a producers factor in the increased feed value of Royal barley, the increased safety of the alfalfa, and the increased alfalfa production during the seeding year, Royal barley maintains a clear advantage over other cereal grains and/or mixtures containing peas.  Ultimately, producers will have to weigh the risks, rewards, and costs of each method of establishing alfalfa stands.