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UPCOMING EVENTS
October 18-22	American Society of Agronomy Meetings – Baltimore, MD
January 26-27, 1998	Wisconsin Forage Council Symposium – Paper Valley Hotel, Appleton, WI
February 21-26, 1999	American Forage and Grassland Council Meeting – Omaha, NE

IN THIS ISSUE
Pages 2 & 3	Planting And Harvesting Corn Silage
Page 3	Late Summer Seeding Of Forage Grasses
Page 4	Alfalfa Cutting Schedule For 1998 Considering Early First Cutting
Page 5	Cutting Hay In The Afternoon Vs. The Morning
Page 5	Wisconsin Forage Council Forage Expo A Success
Page 6	Forage Spokesperson Contest

Planting and Harvesting Corn Silage

By Dan Undersander, UW-Madison

We have traditionally considered that corn for silage could be planted later than for grain, that a later maturity hybrid could be used and it could be planted at higher seeding rates than for grain. These practices are acceptable if we are thinking only of corn silage yield. However, as we feed corn silage to milking dairy cows and stocker cattle, forage quality of corn silage becomes an important consideration.

Maximizing yield of high quality corn silage changes the above recommendations considerably. The data from a study by Joe Lauer at UW Arlington Research Station clearly shows that corn for silage should be planted at the same date as generally accepted for grain. Delaying planting corn silage reduced milk per acre by 270 lbs per acre per day. We consider that delaying corn grain planting beyond the optimum costs one bushel per acre per day. This means that delaying corn grain planting cost about $2 per acre per day, while delaying corn silage planting costs about $35 per acre per day.

The graph also shows that when planting is delayed, shifting to a mid-season hybrid produces more milk per acre than staying with the full season hybrid. This indicates that we should switch to shorter season hybrids for corn silage as planting is delayed, and that we should not plant a hybrid with later maturity for corn silage than we would plant for grain.

Another change in recommendations when corn silage is grown for dairy cows (where both yield and quality are important) is to use the same seeding rate as when corn is planted for grain. It is true that increasing the seeding rate above that recommended for grain will increase yield slightly, but forage quality it lost. Forage quality declines as plant population increases because grain to stove ratio is decreased (less grain at higher plant populations) and because, at higher populations, the plant tends to have more stem and less leaves.

Thus the data indicates that we should plant corn for silage on the same date, at the same seeding rate and the same maturity hybrid as when corn is planted for grain.

The other critical aspect of making good corn silage is to harvest at the right time. Corn must be harvested when dry enough for storage, but not below the optimum storage range because corn silage rapidly declines in quality if harvested too mature. As the plant matures, the kernels harden and pass through the animal (unless processed) and the stover becomes less digestible. The desirable storage moisture depends on the type of silo the silage is being stored in. Silage should be stored in upright silos at 60 to 65% moisture. Silage can be stored in bunker silos or silo tubes at 65 to 70% moisture. Due to lack of pressure from above, these silos will not have leachate losses at the higher moisture contents. Silage can be stored in oxygen-limiting silos at 55 to 65% moisture, slightly drier than for other silo types because of reduced spoilage potential.

There is no clear visible sign on the corn plant to indicate when to harvest. We use to recommend milkline as an indicator, but have found that the plant moisture content varies greatly with a given milkline depending on the hybrid. We now recommend that one use milkline to determine when to begin sampling and determining moisture for harvest. When harvesting for silo bunkers or tubes, one should begin sampling plants for moisture at 3 milkline and determining plant moisture. Some hybrids will be at or below 70% moisture, and others may need additional drying. When harvesting for upright silos, one can weight to 2 milkline to begin sampling for moisture.

A number of forage councils are providing rate of drying information to members. This is done by allowing producers to bring in several corn plants, the plants are chopped through a shredder and then moisture content determined. This information can give farmers an indication of corn silage moisture in the region, but each producer should check his own fields as different planting dates, soil types and hybrids will change the plant moisture content on any given day.

LATE SUMMER SEEDING OF FORAGE GRASSES

Each year questions arise as to the latest date to seed forage grasses in fall. Our recommendations for alfalfa have been to seed at least 6 to 8 weeks prior to the average date of the first killing frost. This means mid-August for much of the state. Less is known concerning the latest safe date to seed forage grasses. Lou Greub and Dan Undersander conducted seeding trials at UW-River Falls using six different forage grasses (Smooth Bromegrass, Timothy, Reed Canarygrass, Perennial Ryegrass and Creeping Foxtail), and five different seeding dates (Early August, Mid-to-late August, Mid-September, Early October and Mid-to-late October). The study was seeded in 1995, 1996 and 1997.

In two of the three years, all species, except Reed Canarygrass, survived and established acceptable stands when seeded as late as September 15. Later plantings either did not germinate or germinated and winter killed. Reed Canarygrass survived consistently only in the August plantings. In 1997, dry weather prevented germination of all species in the earlier plantings until later in the fall, and most winter killed as a result.

This research suggests that forage grasses can be seeded later into the fall than can alfalfa. These grasses, except Reed Canarygrass, may be seeded up to September 15. Reed Canarygrass, however, should be planted no later than September 1. Lack of moisture for adequate germination is always a greater risk when seeding at this time, compared to a spring seeding. Likewise, lack of snow cover or extremely cold temperatures may result in injury even when grasses are seeded by the above dates. Earlier planting will help minimize these risks. Fall seeded grasses should not be grazed or cut for hay until the following year.

With the early spring and early first cutting (at least those that harvested by scissors clip), many are asking about the cutting schedule for the remainder of the season. There is no clear cut answer because of the different economic situations and the fact that a few days difference in growth can make a great difference in plant response.

Let me list a few considerations for individuals to consider when taking the remainder of this seasons cuttings:

· Frequent harvest with short cutting intervals (30 days or less) puts stress on the alfalfa and can reduce winter survival and first cutting yield next year.

· Conversely, a long interval (45 days or more) between cuttings can rebuild plant condition and enhance winter survival.

· Cutting after September 1^st can reduce winter survival and first cutting yield next year due to inability to rebuild root reserves

· Forage quality changes little during September. Thus, a field nearly ready to harvest in early September will have approximately the same forage quality in early October.

· September growth is generally not very great due to fall dormancy in alfalfa.

· Due to good yields this year, the market value of alfalfa will be low, and it will be difficult to sell unless very high quality.

If the fourth cutting can be taken by August 25^th, then the stand will be in good condition for winter. However, a fifth late fall cutting will weaken the stand, which will likely cause stand thinning over winter and reduced yield next spring (about 0.5 t/a less yield). This fifth cutting will likely be low in yield; and therefore, expensive per ton harvested.

Generally, if the alfalfa is beginning to bloom after the 1^st of September in central Wisconsin, or after the first week of September in southern Wisconsin, it is better to wait until early October to harvest. There will be little change in forage quality, tonnage may increase slightly, and, most importantly, the stand will go into the winter in better condition.

Those who have taken only three cuttings before September 1^st and then take a late fall cutting with at least a 45 day interval since the last cutting can do so with little stand damage in average to mild winters.

As the above indicates, the “right” answer for the producer depends on the timing of the previous cuttings and the value of the alfalfa to the individual vs. risk of winter injury.

One of the state Ag newspapers recently reported some research suggesting that alfalfa hay cut in the afternoon was higher in sugars and more palatable than morning cut hay. However, note that this data was from Utah and does not apply to Wisconsin.

It is certainly true that we see a diurnal trend in leaf carbohydrates, with the highest levels being in the afternoon on days when the alfalfa is actively growing. This occurs because as plants photosynthesize during the day, they make sugars and starch faster than it can be moved out of the leaf to growing and storage locations. This means that leaf nonstructural carbohydrate is highest in the late afternoon on good growing days. The sugars and starch continue to move out of the leaf during the night when photosynthesis is not occurring, so the lowest level of nonstructural carbohydrate in the leaf occurs just before sunrise.

Thus, if we cut alfalfa late in the afternoon, it has higher nonstructural carbohydrates than hay cut at other times. But, what counts is how much nonstructural carbohydrates are in the harvested hay, not how much was there when the hay was cut. Hay does not dry as rapidly in Wisconsin as in the West. After an alfalfa plant is cut, it continues to respire (break down sugars) until it dries beyond a certain point. Out West this point is reached rapidly, and the higher sugar levels are maintained in the plant through baling. Here the drying rate is lower and plants cut in the afternoon may continue to respire all night, while alfalfa cut in the morning will dry in a shorter time and quit respiring in the afternoon. The net result is that, in the Midwest, plants cut in the afternoon start with higher sugars, but usually do not have higher sugars at baling than alfalfa cut in the morning. An afternoon cutting also adds half a day to drying time and increases the chance of rain on the hay.

The only time when mowing in the afternoon would be better for us in the Midwest would be when alfalfa can be cut and harvested in the same day for haylage.

ANNOUNCING THE FIFTH ANNUAL

WISCONSIN FORAGE COUNCIL

Come talk to other farmers about forage operation on your farm

HELD IN CONJUNCTION WITH THE WFC ANNUAL SYMPOSIUM IN APPLETON, WISCONSIN

JANUARY 26 AND 27, 1999

CONTESTANTS GIVE A 15 MINUTE PRESENTATION ON THEIR

FORAGE PRODUCTION PRACTICES

FIRST PRIZE -

UP TO $1000.00 TO ATTEND THE AMERICAN FORAGE AND GRASSLAND COUNCIL SYMPOSIUM AND

NATIONAL FORAGE SPOKESPERSON CONTEST HELD FEBRUARY 21 - 26 IN OMAHA, NE

CASH PRIZES FOR 2^ND - 4^TH PLACE

FOR MORE INFOMATION CONTACT DENNIS COSGROVE AT 715-425-3345