Clarence Renk, Manager, Western Agricultural Research Station, OARDC
Joe Davlin, Assistant 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 2011, including commercial varieties of alfalfa, red clover, white clover tall fescue and annual ryegrass in tests planted in 2008 to 2011 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, (available online at http://ohioline.osu.edu/b472/0008.html).

Interpreting Yield Data

Yield data are reported in Tables 2 through 11. 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.

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.
Consider these factors when selecting alfalfa varieties for Ohio:

1. Yield. Yield is the major factor in determining 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 yield. Varieties that perform equally well across several locations and years are probably adapted to a wider range of environmental conditions. Stable yield performance across several environments is important because soils may vary on your farm and weather conditions vary from year to year. Conditions on most farms are such that several varieties may perform equally well.

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

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 to grow earlier in the spring and later into the fall, extending the growing season. 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 varieties released in the mid-1990’s yielded more and persisted longer than older varieties, primarily because of improved resistance to diseases that affected the trial.

5. Insect resistance. Alfalfa varieties have been developed for resistance to potato leafhopper (PLH), which is the most consistently damaging insect pest of alfalfa in Ohio. This report includes several trials where yield tolerance to PLH damage is being evaluated. The PLH resistant varieties are not resistant to the alfalfa weevil, and they will need to be protected from that pest like all standard alfalfa varieties when weevil populations exceed the economic action threshold. For more information on insect management in alfalfa, see the following website:

6. Compare to check variety. For comparisons of varieties across several trials, always compare varieties to the same check planted within the trial. The variety Vernal is used as a check in all Ohio trials.

7. Use good management. No variety can produce well under poor management. Good management considers all aspects of alfalfa production: seed bed preparation, liming and fertilization, seeding, pest control, harvest, storage, and post harvest treatment. Many newer varieties are better adapted to intensive management.

Summary of 2011 Crop Conditions

Rainfall was above normal for the season at all locations and monthly departures were above normal with only a few exceptions (Table 1). At South Charleston and N. Baltimore rainfall was more than 10 inches above the long-term average. Temperatures were well above normal for most of the growing season with the exception of September at S. Charleston and August and September at N. Baltimore and few exceptions (Table 1).

Alfalfa

The trials at North Baltimore had the highest yields, averaging over 8 tons/acre and higher than the average yield in 2010. A new spring seeding at South Charleston had to be delayed until August due to the wet weather. First harvest yields at South Charleston and Wooster were well below normal due to the rainfall. Alfalfa stands at S. Charleston declined significantly during the growing season. Alfalfa weevil populations were low at all sites and no insecticide was required for their control. Insecticide applications were used at all locations for control of potato leafhopper (PLH) in the standard yield trials. No insecticide was applied to control PLH in the alfalfa yield trial used to assess potato leafhopper resistance at South Charleston, seeded in 2008 (Table 6). High leafhopper populations resulted in significant yield differences among varieties at the June, July, and September harvests in 2011 and the total over four years in that trial. Leafhopper resistant varieties are not resistant to alfalfa weevil, and need to be treated with insecticides if weevil populations exceed action thresholds.

Potato Leafhopper Resistant Alfalfa

No insecticide was applied to control potato leafhopper in the alfalfa yield trial for potato leafhopper resistance conducted at South Charleston, Ohio. High leafhopper populations resulted in significant yield differences among varieties. Leafhopper resistant varieties are not resistant to alfalfa weevil, and will need to be treated with insecticides if weevil populations exceed action thresholds.

Clover: Red & White

Red and white clover trials were seeded in 2010 at South Charleston. Trials were sprayed after the first harvest for potato Leafhopper (PLH) control to aid new growth due to the high numbers of PLH. Red clover is better adapted than alfalfa to soils that are somewhat poorly drained and slightly acidic; however, greatest production will occur on well-drained soils with high water-holding capacity and pH above 6.0. Red clover is not as productive as alfalfa in the summer and it generally persists for a shorter time than alfalfa. New varieties are capable of persisting into a third year. While clover is a short-lived perennial that is well suited for pastures. It spreads and persists over time by vegetative propagation of stolons and by natural reseeding. White clover tolerates periods of poor drainage.

Tall Fescue

The tall fescue trial of endophyte-free varieties established at South Charleston in 2008 averaged 4.71 tons/acre. New varieties that are endophyte free or that contain a non-toxic endophyte (eg., Jessup Max Q) have potential to increase animal performance, especially during the summer grazing season, and to provide forage for beef cattle and sheep during autumn and early winter.

Annual Ryegrass

Table 10 reports yield of the trial seeded in fall 2010. Due to low rainfall there was no harvestable yield in the fall of 2010. Therefore, total yield represents dates collected in 2011 only. The first harvest was later than usual, which increased yield (but lowered forage quality), the warm and moist summer conditions in 2011 promoted excellent growth.

Table 11 reports yield of the trial seeded in September of 2011 and includes only one harvest date this November. That trial will be continued into 2012 where ranking of varieties may change. Annual ryegrass is a cool-season annual bunch grass that is highly palatable and digestible. It has high seedling vigor and is well adapted to either conventional or no-till establishment methods.

Inclusion of entries in Ohio Alfalfa Performance Trials does not constitute an endorsement of a particular entry by The Ohio State University, Ohio Agricultural Research and Development Center, or Ohio State University Extension. Where trade names appear, no discrimination is intended, and no endorsement is implied by The Ohio State University, Ohio Agricultural Research and Development Center, or Ohio State University Extension.

Go to Ohio Crop Performance

11/2011
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Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, Keith L. Smith, Director, Ohio State University Extension.