2013 Ohio Forage Performance Trials

Authors:

J.S. McCormick, Research Associate, Department of Horticulture and Crop Science

R.M. Sulc, Professor / Extension Forage Agronomist, Dept. of Horticulture and Crop Science

D. J. Barker, Professor, Department of Horticulture and Crop Science

Contributors:

Joe Davlin, Manager, Western Agricultural Research Station, OARDC
Matt Davis, Manager, Northwest Agricultural Research Station, OARDC
Lynn Ault, Manager, Schaffter Farm, Wooster, OARDC

SUMMARY

This report is a summary of performance data collected from forage variety trials in Ohio during 2013, including commercial varieties of alfalfa, red clover, white clover and annual ryegrass in tests planted in 2010 to 2013 across three sites in Ohio: South Charleston, Wooster, and North Baltimore. For more details on forage species and management, see the Ohio Agronomy Guide, Ohio State University Extension Bulletin 472, which can be purchased from Ohio State University Extension's eStore at http://estore.osu-extension.org/.

Interpreting Yield Data

Yield data are reported in Tables 2 through 10.  Details of establishment and management of each test are listed in footnotes below the tables.  Least significant differences (LSD) are listed at the bottom of Tables 3 through 10.  Differences between varieties are significant only if they are equal to or greater than the LSD value.  If a given variety out yields another variety by as much or more than the LSD value, then we are 95% sure that the yield difference is real, with only a 5% probability that the difference is due to chance alone.  For example, if variety X is 0.50 ton/acre higher in yield than variety Y, then this difference is statistically significant if the LSD is 0.50 or less.  If the LSD is 0.51 or greater, then we are less confident that variety X really is higher yielding than variety Y under the conditions of the test.

The CV value or coefficient of variation, listed at the bottom of each table is used as a measure of the precision of the experiment. Lower CV values will generally relate to lower experimental error in the trial. Uncontrollable or unmeasured variations in soil fertility, soil drainage, and other environmental factors contribute to greater experimental error and higher CV values. However, higher CV values can also occur simply as a result of the mean yield being low (eg. due to weather conditions), because the CV is a function of the mean yield. So a higher CV will often occur where yields are low despite there being no increase in experimental error.

Results reported here should be representative of what might occur throughout the state but would be most applicable under environmental and management conditions similar to those of the tests.  The relative yields of all forage legume varieties are affected by crop management and by environmental factors including soil type, winter conditions, soil moisture conditions, diseases, and insects. 

 ALFALFA

Alfalfa has the highest combined yield and quality potential of any adapted perennial forage grown in Ohio.  It is the state's largest single hay crop, being grown on about one-half of the total hay acres.  Alfalfa requires well-drained soils with near-neutral pH (6.5-7.0) for greatest production and persistence.  Alfalfa trials are initiated each year and data is collected for at least four years unless the stand becomes so depleted that further testing is no longer worthwhile; variety performance should be evaluated over several sites and years.

 Guidelines for Selecting Alfalfa Varieties

To capitalize on alfalfa's potential, select high-yielding varieties with resistance to problem diseases. Alfalfa variety rankings for a number of traits described below are reported on the University of Wisconsin forage website, at http://www.uwex.edu/ces/forage/pubs/varinfo.htm.

Consider these factors when selecting alfalfa varieties for Ohio:

1.      Yield.  Yield is critical to profitability of an alfalfa stand. Select varieties with high yields over several locations and years. Table 2 shows this comparison in percent of the average test yield. Varieties that perform equally well across several locations and years are adapted to a wider range of environmental conditions, which is important because soils may vary on your farm and weather conditions vary from year to year.

 2.      Persistence.  Another important consideration is how long the alfalfa stand will last. Study variety performance by age of stand to get an estimate of longevity of productivity. Some varieties may decline with age more rapidly than others, which may influence your variety choice depending on how long you intend to keep the stand. For long-term rotations, choose varieties with good disease resistance and good performance in the fourth year. If you plan to harvest alfalfa for three years or less, then high performance during the first three years should be given priority.

 3.      Fall dormancy (FD).  Alfalfa varieties with fall dormancy ratings of 1 through 5 are considered adequately winter hardy for Ohio conditions while those of 6 or higher are not considered adapted. Varieties with higher fall dormancy ratings tend to grow at a lower temperature, so they begin growth earlier in the spring and continue growth later into the fall. The fall dormancy rating does not correlate well with winter hardiness within the range of varieties adapted to the Midwest USA.

 4.      Disease resistance.  Variety selection based on yield performance alone is less satisfactory than selections that also consider disease resistance characteristics. Resistance to specific disease-causing pathogens may be the most important attribute in an alfalfa variety. Pathogens can dramatically reduce yield and persistence of susceptible varieties. In an evaluation of older versus newer alfalfa varieties we found that newer varieties yielded more and persisted longer than older varieties, primarily because of improved resistance to diseases that affected the trial.