This spring early March temperatures in the 70’s had many concerned about the effect on alfalfa. Much of our alfalfa had broken dormancy and was showing varying levels of new growth. The extent to which this damages the plants depends on the weather as we head into spring. If temperatures stay mild, there will be few problems. If on the other hand temperatures turn cold, there could be some effects. As of this writing, it is too early to tell the impact of this weather, but here are a few possible outcomes.

1. Delayed Green-up - The crown buds which give rise to this early growth were actually formed last fall. If they begin growth and are then killed, the plant will have to make new buds, which will delay the actual green-up to some extent.

2. Low carbohydrate reserves - Some of the carbohydrates which would normally fuel early spring growth will have been used up, giving rise to the growth that was killed. This likewise may delay green-up and make for weakened plants.

3. Tissue or plant death - The worst case is that plants completely de-harden and will be killed by very cold temperatures.

What to do?

Delayed Green-up

Wait! Don’t decide to tear up a stand until you have given it adequate time to replace damaged crown buds and re-grow. Dig up a few plants and feel them. If they are soft and watery, they are probably dead. If they are nice and white and firm, they are probably okay and just need some time.

Low Carbohydrate Reserves

Again, wait a while to evaluate re-growth. At some point in the season, the stand should be allowed to grow to 10 to 25 percent bloom in order to replenish low reserves. Ideally, this would occur in third cutting as the quality reduction associated with delayed harvest is much less at that time. If a fall cutting was taken, the stand is an old one, or for some other reason the stand seem severely weakened, first cutting may be a better alternative. Just keep in mind that quality will be low.

Tissue or Plant Death

Evaluate the roots as described above. If the plant is mushy, watery and a grayish color when split, it is dead.

In many areas of Wisconsin, the first cutting of alfalfa forage resulted in excellent yields, filling or nearly filling the silage storage structures on many dairy farms. Therefore, many alfalfa producers are looking to harvest their second cutting of alfalfa as intermediate (about 30 inches by 30 inches by 5 feet) square bales. This is an excellent method for handling dry alfalfa hay especially if it is going to be marketed.

Because the intermediate square bales are denser than small square and large round bales, the recommended storage moisture is two to three percent less than small rectangular bales. Recommended bale moisture levels for storage with minimal losses may be difficult to attain in humid Wisconsin weather conditions. Harvesting large square bales above 17 percent moisture will require a preservative for good bale storage or plastic wrap may be used to maintain forage quality.

Preservative Research Results (Wisconsin)

In 1997 and 1998, Shinners studied preservatives and ventilation holes for intermediate square bales at moistures from 14 to 28 percent. The preservatives were propionic acid and a bacterial inoculant. Ventilation holes of three and five inches in diameter were two treatments evaluated for reducing dry matter loss and maintaining forage quality. Four different trials or cuttings were evaluated. Following are his findings:

· bales treated with propionic acid maintain higher moisture during storage

· propionic acid produced less heating at the higher moisture content

· ventilation holes in the bales did not produce less heating

· none of the methods reduced dry matter loss

· dry matter loss was less than 4% when baling at moistures below 16%.

Bale Wrapping Research Results (Wisconsin)

At the Lancaster Agricultural Research Station, plastic wrapping of intermediate bales was evaluated for bales at 21 to 40% moisture during 1997. Undersander and others studied the effect of time between baling and wrapping and the number of plastic layers. Following are their results:

· bales (800-1200 lbs) need to have 2 to 3% less moisture at baling than small squares

· bales should be wrapped within 24 hours after baling

· plastic wrapping bales at 21 to 38% moisture adequately preserved them

· four layers of 1.5 mil plastic(50% overlap, twice over) was adequate

Bale Silage Storage Using Plastic (Wisconsin)

In a study conducted in the late 1980’s, Straub and others evaluated plastic covers, bags and wrap with round bale silage. The plastic covers were used to protect the bales stacked three high in a triangular formation. Bale bags were designed to enclose one bale each. Also the use of propionic acid was evaluated. They found:

· bale wrapping produced the most reliable results

· a preservative is needed with bales bags and covers

Limited research results are available on bale tubes and line wrapping. The key to their success will be their ability to seal the bales and prevent any air from getting inside the plastic.

Preservative recommendations

Some preservatives that have been used are anhydrous ammonia, inoculants and buffered propionic acid. Although anhydrous ammonia costs less, handling and safety problems make propionic acid a better preservative. The recommended application rates for large square bales are listed in Table 1, where the propionic acid concentration is 75 to 80 percent. If the acid concentration is less more chemical will need to be added.

If the solution contains other acids such as acetic or citric acid, it will be less effective than a solution containing only propionic acid. Acetic acid is considered to be about one third as effective as propionic acid. Therefore, you would need three times more acetic acid to have the same effect as the recommended rate of propionic acid. For bacterial inoculants, the manufacturer’s recommendations should be followed.

The estimated cost for the acid solution is about $0.95 per pound. This is based on a 55 gallon drum costing $450. The cost of the spraying system including a pump, tank, valve, nozzle and other miscellaneous parts should added to the values in Table 1, but should be less than $1.00 per ton. Costs will be less when the acid is purchased in the off season in large quantities.

The key to selecting the correct application rate will be determining the forage moisture content. An accurate method must be used and good representative samples must be obtained. There can be a large variation in forage moisture in the windrow, so sampling will be very important.

Table 1. Recommended application rates of propionic acid.
Moisture Content	Rate (%)	Rate (lbs/ton)	Cost ($/ton)
17-19	0.4	8	$7.60
20-22	0.6	12	$11.40
23-24	0.8	16	$15.20

Congratulations to our Award Winners:

Outstanding Forager – Richard Vine, Granton

Outstanding Educator – Mike Ballweg, Sheboygan County

Agri-Business – Bob Bosold, WAXX Radio, Eau Claire

Honorary Life Member – Dr. Richard Smith, Madison

Congratulations to our Pacesetters:

Joe & Diane Tiry – Chippewa County

Brad & Pam Wolf – Clark County

George Roemer – Dodge County

John & Karen Ruedinger -- Fond du Lac County

Mike Sulzer – Green County

Joseph Holschbach – Manitowoc County

Jerome & Mona Jaeger – Manitowoc County

Allen & Jean Timm – Outagamie County

Brian & Jeanne Goeser – Sheboygan County

Manure and Alfalfa -
a complicated management mix

Dairy producers typically have a significant number of alfalfa acres and lots of manure. These two entities create a unique problem. Both are sources of nitrogen (N) for cereal crops. Alfalfa in the rotation has the overall effect of reducing the N recommendation for corn. As stated many times before, the need for more than about 40 lbs. N per acre is rare for first-year corn following alfalfa. This is the equivalent of about 10 tons of solid dairy manure or 4000 gallons of liquid manure. While corn following corn offers the most opportunity for efficient manure application, many producers do not have enough acres in this situation to make a big dent in manure inventories. Additionally, where no manure storage system is in place, there is a need to apply manure year around. For these reasons, many producers are now looking to the alfalfa crop as an outlet for applying manure in an economically and environmentally sound manner. Two options exist and are discussed here.

Apply manure before alfalfa establishment

Applying manure to alfalfa prior to seeding breaks tradition from the standpoint that manure-N is being applied to a legume. However, such an application can result in significant P and K contributions for the seeding and subsequent years. Also, a majority of the manure N will be utilized by the crop rather than leached to groundwater as would be the case where large applications are made following alfalfa and before corn.

A number of recent research studies have examined the potential for pre-seeding manure applications. In Minnesota, a four-year study resulted in increased alfalfa yields on both medium and high P and K testing soils where manure applications up to 12,000 gallons per acre were applied. The yield increases also tended higher than increases associated with comparable rates of commercial fertilizer applications. Similar responses have also been obtained in several Wisconsin experiments where up to 24,000 gallons per acre of manure were applied. Increased yields in all cases carried through the first full production year. It's thought that secondary or micronutrients contained within the manure may be responsible for the yield benefits above that of applied fertilizer. Other factors may include improved soil tilth, earlier N availability, and increased microbial activity.

The application of manure to alfalfa prior to seeding should only be used where the crop is direct seeded or the companion crop is removed as forage. Applying high rates of manure where the companion crop is harvested as grain will likely result in significant lodging of the small grain. Weed infestations from manure applications made pre-seeding have proven to be variable. Research experiences show little difference in weed pressure between control and manured plots; however, some producers have noted increased infestations as a result of manure applications prior to alfalfa seeding.

Topdress manure onto established alfalfa

Topdress applications of manure are often made because of the necessity to spread manure during the summer months. They can result in improved yields and stand persistence, however, they may also be detrimental to an alfalfa stand. The latter effect may originate from several sources. The first potential injury is from the manure's N. Plant growth will slow or stop where free ammonia from the manure is released. Manure also contains many salts that when placed in contact with plants, will burn or desiccate leaf tissue.

Less visible, but just as important, is the potential for crown damage caused by driving application equipment over plants. Large equipment will also contribute to soil compaction, whereby plant growth and nutrient uptake are affected. Both liquid and solid dairy manure can cause problems. While liquid manure generally "coats" the alfalfa foliage more thoroughly, there is more localized damage from solid manure where large clumps are left in the path of the spreader.

With the potential for alfalfa plant injury, Michael Schmitt, University of Minnesota Extension Soils Specialist, offers these criteria to select the best suited fields for manure applications:

Age of stand: There is more to risk by making applications to a younger stand that has a higher yield potential compared to an older stand.

Alfalfa density: Poorer stands of alfalfa tend to have more grasses contributing to overall yield. Grasses are more tolerant to topdressed manure applications than alfalfa and will directly benefit from manure N. With thin alfalfa stands, manure applications may increase forage yield at the expense of the legume in the stand.

Soil nutrient status: Where fertility is limiting production, the overall effect of a topdressed manure application may be better production because the response from applied nutrients was greater than other injury related factors. Therefore, choose those fields with the lowest fertility.

When making topdress manure applications to alfalfa, apply relatively low rates-----3,000 - 7,000 gallons of liquid manure or no more than 10 tons of solid manure per acre in a single application. Additionally, applications should be made immediately after removing a cutting so manure contacts the soil instead of the foliage. This will reduce the risk of salt burn and avoids palatability problems. Make applications only when the ground is firm and dry to minimize compaction problems.

Summary

The alfalfa crop provides an additional option for producers to apply manure in a manner that is agronomically, economically, and environmentally beneficial. Applications made prior to seeding is an under utilized management practice that results in an efficient means to apply phosphorus, potassium, and other nutrients needed by alfalfa. Research results have shown yields may increase more than when only inorganic fertilizer sources are used. Topdressing manure on established alfalfa fields is more risky but can provide benefits if fields are properly selected and application guidelines are followed. Because of alfalfa's high value, a corresponding high level of management is needed with either manure application option to limit crop injury and subsequent yield potential.

Check us out on the Internet at:

http://www.uwex.edu/ces/forage/wfc.htm

Thanks to all who attended the 2000 Wisconsin Forage Council Annual Meeting and Symposium. To better understand your needs for future Symposiums, we sent out a short Survey to all those that registered and attended this year. As of this Newsletter, we received 67% of the surveys back (THANK YOU), and would like to summarize some of the results for you. If you received a survey and have not returned it yet, please do so at your earliest convenience.

· 71% have previously attended a Wisconsin Forage Council Symposium

· 69% prefer to keep the Symposium a 2-day event, rather than change it to a 1-day event

· 50% want to leave the Symposium on a 3-year rotation between the Dells, Eau Claire and Appleton, and 29% would like to see it always hosted in the Dells

· 73% have never visited the Forage Council’s website

· 70% think the WFC Symposium should remain oriented primarily to farm and agribusiness audiences

· 74% spent over one-half hour talking with exhibitors

· 30% rated the quality of the 2000 Symposium as Excellent, 61% rated it Good and 9% rated it Fair

· 59% said the quality of information this year was useful and they may try some new practices. 24% said it was very useful and will adopt what they learned

· 79% felt the registration fee was in line with the value of the program

· 90% felt the topics presented were timely and important

Many people shared their comments about the program with us. Thank you very much as we are taking a close look at each and every comment to try to improve the Symposium in the future. Thanks again for your response!

Volume 24, Number 1, April 2000

Warm Weather and Alfalfa by Dennis Cosgrove

Delayed Green-up

Low Carbohydrate Reserves

Ronald T. Schuler – Extension Agricultural Engineer

Summary