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.
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 3 shows this comparison in percent of the mean. 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 performance in the fourth or fifth 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. Thus they begin to grow earlier in the spring and later into the fall, extending the growing season. Until recently it was generally felt that fall dormancy rating was very closely correlated with winter hardiness. This relationship with modern varieties seems less dependable. Now, for example, a variety with a "2" dormancy rating may not always have greater cold tolerance compared to one with "3" fall dormancy rating. Fall dormancy ratings provided by the seed industry are given in Table 1.
4. Disease and pest 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. For example, Phytophthora root rot resistance is often very important on soils that are less than well-drained. The disease resistance characteristics of alfalfa varieties included in this report and their local seed marketers are listed in Table 1. Below is an explanation of the information found in Table 1.
a. Bacterial Wilt (Bw) and Fusarium Wilt (Fw) Nearly all alfalfa varieties currently grown in Ohio have resistance to Bacterial Wilt and Fusarium Wilt. The widespread use of these varieties has greatly diminished the significance of these diseases. However, severe losses can still be incurred in stands of susceptible varieties.
b. Verticillium Wilt (Vw) First detected in Ohio in 1984, this disease still has limited distribution within the state, having been confirmed on 17 farms in 9 Ohio counties. It has been found in Ashland, Columbiana, Franklin, Holmes, Knox, Logan, Medina, Stark, and Wayne Counties. Verticillium Wilt is usually introduced into a field on infested seed and generally does not become a problem until the third production year. Scattered plants become yellow and stunted and gradually die, leaving a thin, unproductive stand.
c. Anthracnose (An) Anthracnose occurs during hot, rainy weather. The fungus attacks individual stems and grows into the crown, causing a crown rot and eventual death of the plant. Severe losses can occur the second and third year after seeding in stands of susceptible varieties.
d. Phytophthora Root Rot (PRR) This disease typically occurs in heavy or poorly drained soils. However, when any soil becomes water saturated, the fungus may invade the taproot and destroy the plant. Even resistant varieties are fairly susceptible to Phytophthora in the seedling stage.
e. Root Knot Nematode (RRN) Damage from Root Knot Nematode is most likely to occur on sandy or organic (muck) soils. Small galls or 'knots' form on roots. These may be confused with nitrogen-fixing Rhizobium nodules.
f. Aphanomyces root rot may contribute to poor alfalfa establishment and reduced growth in wet soils. Seedlings may die (damping off) if infection occurs at an early stage of development. Older seedlings are yellowed and stunted. When aphanomyces and phytophthora occur together, they form a destructive disease complex.
5. 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.
6. Forage Quality. Consider planting some fields to high quality varieties and some to standard varities to spread the harvest window in the spring. Forage quality of selected varieties is reported in this publication (Table 13).
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.
| Table 1: Characteristics of Alfalfa Varieties Listed in This Report. | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
***Ratings were supplied by the seed industry and were not verified by university testing.*** The abbreviations for the column headings are: (FD) Fall Dormancy; (Bw) Bacterial Wilt; (Vw) Verticillium Wilt; (Fw) Fusarium Wilt; (An) Anthracnose; (PRR) Phytophthora Root Rot; (RKN) Root Knot Nematode; (APH) Aphanomyces Root Rot Race 1. Resistance Key: 0-5% = susceptible (S); 6-14% = low resistance (LR); 15-30% = moderate resistance (MR); 31-50% = resistance (R); >50% = high resistance (HR). If the resistance rating for a variety is not listed, then the variety is susceptible or has not been adequately tested. | |||||||||
| Variety | Marketer | FD | BW | VW | FW | AN | PRR | RKN | APH |
| 631 | Garst Seeds | 4 | HR | R | HR | R | HR | -- | MR |
| 645 | Garst Seeds | 3 | HR | R | R | HR | HR | -- | MR |
| 2833 | Novartis Seeds | 3 | HR | R | HR | HR | HR | -- | -- |
| 3324 | L. Herried Seed | 3 | HR | R | R | HR | HR | -- | R |
| 5246 | Pioneer | 3 | HR | R | HR | HR | HR | -- | MR |
| 5312 | Pioneer | 3 | HR | HR | HR | HR | HR | -- | R |
| 5347LH | Pioneer | 3 | R | MR | R | HR | HR | -- | R |
| 5373 | Pioneer | 4 | HR | R | HR | HR | MR | -- | LR |
| 5454 | Pioneer | 4 | R | MR | HR | HR | HR | -- | LR |
| 8920 MF | Pickseed Co. | 2 | HR | R | HR | HR | HR | -- | -- |
| Variety | Marketer | FD | BW | VW | FW | AN | PRR | RKN | APH |
| ABT 405 | Scott Seed | 4 | HR | HR | HR | HR | HR | -- | R |
| Ace | Provico Inc. | 4 | HR | R | HR | HR | HR | -- | R |
| Achieva | Agway/Allied | 3 | R | R | HR | HR | HR | -- | R |
| Affinity + Z | America's Alfalfa | 4 | HR | HR | HR | HR | HR | -- | R |
| Aggressor | America's Alfalfa | 4 | HR | R | HR | HR | HR | -- | MR |
| Alpha 2001 | Great Lakes Hybrids | 4 | HR | HR | HR | HR | HR | -- | R |
| AlfaGraze | America's Alfalfa | 2 | R | -- | R | MR | LR | -- | R |
| AlphaStar | Steyer Seeds | 4 | HR | R | HR | HR | HR | -- | R |
| Amerigraze 401+Z | America's Alfalfa | 4 | HR | R | HR | HR | HR | -- | R |
| Ameriguard 301 | America's Alfalfa | 3 | HR | R | HR | HR | HR | -- | R |
| Variety | Marketer | FD | BW | VW | FW | AN | PRR | RKN | APH |
| Apollo Supreme | America's Alfalfa | 4 | HR | R | HR | HR | R | -- | -- |
| Arrest | Novartis Seeds | 3 | R | HR | HR | HR | HR | -- | R |
| Arrow | America's Alfalfa | 3 | HR | R | HR | MR | HR | -- | -- |
| Asset | Yoder Hybrid/Merrit | 4 | HR | R | R | R | HR | -- | MR |
| Avalanche+Z | America's Alfalfa | 2 | HR | HR | HR | HR | HR | -- | R |
| Banquet | WL Research | 4 | HR | HR | HR | HR | HR | -- | R |
| Belmont | Great Plains | 4 | HR | R | HR | HR | R | -- | -- |
| BH 330 | Beachley Hardy | 4 | HR | R | HR | HR | HR | -- | R |
| Choice | Countrymark | 4 | HR | HR | R | R | HR | -- | R |
| Ciba 2444 | Ciba Seeds | 3 | HR | R | HR | HR | HR | -- | R |
| Variety | Marketer | FD | BW | VW | FW | AN | PRR | RKN | APH |
| Cimarron VR | Great Plains | 4 | HR | R | HR | HR | R | MR | MR |
| Cleansweep 1000 | Countrymark | 3 | HR | R | HR | HR | HR | -- | R |
| Complete | Bird Hybrids | 3 | HR | HR | HR | HR | HR | -- | R |
| Crown II | Cargill | 3 | HR | R | HR | HR | HR | -- | -- |
| Crystal | Mike Braynton Seeds | 4 | HR | R | HR | R | HR | -- | LR |
| Dart | AgriPro | 3 | HR | R | HR | R | HR | -- | -- |
| Dawn | AgriPro | 3 | HR | R | HR | R | HR | -- | -- |
| Demand | AgriPro | 3 | R | HR | HR | HR | HR | -- | R |
| Depend + EV | AgriPro | 4 | HR | HR | HR | HR | HR | -- | R |
| Dividend | Agway/Allied Seed | 2 | HR | R | HR | HR | HR | -- | R |
| Variety | Marketer | FD | BW | VW | FW | AN | PRR | RKN | APH |
| DK121HG | DEKALB | 2.3 | HR | HR | HR | HR | HR | -- | R |
| DK127 | DEKALB | 3 | HR | R | R | HR | HR | -- | HR |
| DK133 | DEKALB | 4 | HR | R | HR | HR | HR | -- | R |
| DK140 | DEKALB | 4 | HR | R | HR | HR | HR | -- | HR |
| DK141 | DEKALB | 4 | HR | HR | HR | HR | HR | -- | HR |
| Dominator | AgriPro | 4 | HR | R | HR | HR | HR | -- | R |
| Excalibur II | Yoder Hybrid/Merit | 3.5 | HR | R | HR | HR | HR | -- | -- |
| GH 797 | Golden Harvest | 4 | HR | HR | HR | HR | HR | -- | R |
| GH 794 | Golden Harvest | 4 | HR | R | HR | HR | HR | -- | R |
| Gem | Countrymark | 4 | HR | R | HR | HR | HR | -- | S |
| Variety | Marketer | FD | BW | VW | FW | AN | PRR | RKN | APH |
| GreenField | Becks Hybrids | 3 | HR | R | HR | HR | HR | -- | R |
| HayGrazer | TMK Farm Service | 4 | HR | R | HR | R | R | -- | MR |
| Homestead | Research Seeds | 3 | HR | R | HR | HR | HR | -- | -- |
| Imperial | America's Alfalfa | 3 | HR | HR | HR | HR | HR | -- | R |
| Innovator + Z | America's Alfalfa | 3 | HR | R | HR | HR | HR | -- | R |
| Interceptor | AgriPro | 3 | HR | R | HR | HR | HR | -- | R |
| Key | Great Plains | 4 | HR | HR | HR | HR | HR | -- | MR |
| Legend | Cenex/Land O'Lakes | 4 | HR | R | HR | HR | HR | -- | -- |
| MagnaGraze | Dairyland | 3 | HR | R | HR | R | HR | LR | R |
| Magnum III | Dairyland | 4 | R | MR | R | MR | R | -- | LR |
| Variety | Marketer | FD | BW | VW | FW | AN | PRR | RKN | APH |
| Magnum III-Wet | Dairyland | 3 | R | MR | R | MR | R | MR | MR |
| Magnum IV | Dairyland | 4 | HR | R | HR | R | HR | MR | MR |
| Multi-Plier | Mycogen Seeds | 3 | HR | R | HR | HR | HR | -- | -- |
| Multistar | Countrymark | 3 | HR | R | HR | HR | HR | -- | -- |
| Mustang | Madison Seed Co. | 4 | HR | R | HR | R | HR | -- | -- |
| Ovation | Callahan Seeds | 4 | HR | HR | HR | HR | HR | -- | R |
| Paramount | Wyffels Hybrids | 3 | HR | R | HR | HR | HR | LR | HR |
| Persist | Doeblers Seed | 4 | HR | R | HR | R | HR | -- | MR |
| Precedent | Doeblers/Wyffels | 4 | HR | R | R | R | HR | -- | R |
| Prism | Beachley-Hardy | 4 | HR | R | R | HR | HR | -- | MR |
| Variety | Marketer | FD | BW | VW | FW | AN | PRR | RKN | APH |
| Prism II | Beachley-Hardy | 3 | HR | R | HR | HR | HR | -- | R |
| Ram | Great Plains | 4 | HR | R | HR | HR | HR | MR | -- |
| Resistar | Countrymark | 4 | R | HR | HR | R | HR | -- | -- |
| Rushmore | Novartis Seeds | 4 | HR | R | HR | HR | HR | -- | HR |
| SafeGuard | Allied Seed | 3 | HR | R | HR | HR | HR | -- | R |
| Spur | Madison Seed Co. | 4 | HR | R | R | MR | R | -- | -- |
| Sterling | Cargill | 2 | HR | R | HR | HR | HR | -- | R |
| Stine 9227 | Stine | 4 | HR | R | HR | HR | HR | -- | MR |
| SuperCuts | Scott Seed | 4 | HR | HR | HR | HR | HR | -- | R |
| Synergy | Crows Hybrids | 3 | HR | R | HR | HR | HR | -- | HR |
| Variety | Marketer | FD | BW | VW | FW | AN | PRR | RKN | APH |
| Tamax Plus | Burtch Seed Co. | 4 | HR | R | HR | HR | HR | -- | -- |
| TMF Generation | Mycogen seeds | 4 | HR | HR | HR | HR | HR | -- | R |
| TMF Mutiplier II | Mycogen Seeds | 3 | HR | HR | HR | HR | HR | -- | R |
| Trailblazer | Cenex/Land O' Lakes | 2.7 | HR | R | HR | HR | HR | -- | MR |
| Total + Z | America's Alfalfa | 3 | HR | HR | HR | HR | HR | -- | R |
| Venture | Yoder Hybrid/Merit | 4 | HR | R | R | HR | R | -- | R |
| VERNAL | Public | 2 | R | -- | MR | -- | -- | MR | -- |
| Webfoot MPR | Great Lakes Hybrids | 4 | HR | HR | HR | HR | HR | -- | R |
| WL 252 HQ | Ohio Seed Co. | 2 | HR | R | HR | HR | HR | -- | LR |
| WL 317 | Ohio Seed Co. | 3 | HR | R | HR | R | HR | MR | -- |
| Variety | Marketer | FD | BW | VW | FW | AN | PRR | RKN | APH |
| WL 322 | Ohio Seed Co. | 4 | HR | R | HR | HR | HR | -- | R |
| WL 322 HQ | Ohio Seed Co. | 4 | HR | R | HR | MR | R | LR | -- |
| WL 323 | Ohio Seed Co. | 4 | HR | R | HR | HR | HR | -- | R |
| WL 324 | Ohio Seed Co. | 3 | HR | R | HR | HR | HR | MR | HR |
| WL 325 HQ | Ohio Seed Co. | 3 | HR | R | HR | HR | HR | -- | R |
| WL 326 GZ | Ohio Seed Co. | 4 | HR | HR | HR | HR | HR | MR | HR |
| WL 332SR | Ohio Seed Co. | 4 | HR | R | HR | HR | HR | MR | HR |
| WL ProGrazer | Ohio Seed Co. | 4 | HR | R | HR | R | R | MR | LR |
Weather conditions were generally cooler than normal at all testing locations (Table 2). Rainfall was below normal for all sites in April, then was adequate through June, but became limiting again in July and August (Table 2). Rainfall at Columbus was well above average, except in April. Some winter heaving was observed in the established trial at Columbus, and Sclerotinia crown and stem rot caused damage in the seeding at Wooster established in August 1996. Sclerotinia infects seedlings in the fall, but the damage is usually not evident until early spring. Late summer seedings are much more prone to infection by this pathogen than are spring seedings. Varieties with improved resistance to Sclerotinia are becoming available; however, the amount of damage in the Wooster seeding was not sufficient to adequately differentiate among varieties.
Spring blackstem was prevalent in many alfalfa fields in the spring and early summer. In an experimental fungicide trial at Columbus (not reported here), spring blackstem reduced first and second harvest yields by 10 to 15%. Lepto leaf spot was prevalent across much of Ohio in the second crop. We observed higher incidence of this foliar disease on alfalfa that had not been treated with insecticides to control potato leafhopper infestations. Anthracnose was also present in susceptible varieties in some parts of the state during the summer months.
Potato leafhopper populations reached extremely high levels during June through August, and caused severe yield reductions where they were not controlled in a timely manner. Unsprayed trials (no insecticide) were established in spring 1997 at Western and Northwest Branches, and dramatic differences among varieties in leafhopper damage and forage yields were recorded at both locations. In addition to these two new seedings, the 1996 seeding at Western to evaluate leafhopper resistance was continued.
New alfalfa trials reported here include the August 1996 seeding
at Wooster and April 1997 seedings at Western and Northwest Branches. A
new spring seeding at Jackson Branch had unacceptable stands due to dry
weather during early establishment. It was re-established successfully
in August (no harvests taken in 1997).
| Table 2: Weather data summary for the 1997 growing season. | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Columbus | Wooster | Western | Northwestern | Jackson | ||||||
| Month | Total | DFA* | Total | DFA* | Total | DFA* | Total | DFA* | Total | DFA* |
| Precipitation (inches of rainfall) | ||||||||||
| Apr | 1.56 | -2.19 | 1.66 | -1.70 | 1.27 | -2.70 | 0.95 | -2.30 | 1.42 | -2.38 |
| May | 6.16 | 1.79 | 5.69 | 1.78 | 5.33 | 0.72 | 7.21 | 3.78 | 4.68 | 0.52 |
| June | 6.95 | 2.47 | 3.07 | -0.88 | 4.50 | 0.34 | 4.22 | 0.65 | 3.69 | -0.04 |
| July | 6.16 | 1.51 | 1.88 | -2.22 | 3.04 | -1.05 | 2.01 | -1.80 | 2.84 | -1.53 |
| Aug | 5.35 | 1.68 | 2.76 | -0.90 | 3.44 | -0.06 | 1.10 | -1.89 | 3.09 | -0.54 |
| Total | 26.18 | 5.26 | 15.06 | -3.92 | 17.58 | -2.75 | 15.49 | -1.56 | 15.72 | -3.97 |
| Average Daily Temperature (oF) | ||||||||||
| Apr | 48.3 | -2.8 | 45.7 | -2.4 | 48.1 | -2.9 | 44.8 | -4.1 | 49.4 | -3.0 |
| May | 56.7 | -4.7 | 53.4 | -5.1 | 56.3 | -5.0 | 53.9 | -5.9 | 57.7 | -4.0 |
| June | 70.1 | -0.3 | 68.4 | 0.8 | 69.9 | -0.3 | 70.4 | 0.9 | 69.9 | 0.0 |
| July | 73.2 | -0.9 | 71.1 | -0.4 | 73.5 | -0.3 | 72.4 | -0.4 | 74.3 | 0.8 |
| Aug | 69.3 | -3.3 | 67.1 | -2.8 | 69.4 | -2.6 | 68.1 | -2.5 | 70.2 | -2.0 |
| *DFA = departure from longterm average | ||||||||||