A quarterly news publication of The Ohio State University Extension, Editors: Clif Little and Mark Sulc
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Contents:

• Effect of Flies on Grazing Behavior
• The Cost of Fertilizing Pastures
• It's Not Too Late to Plan for Fall & Winter Grazing
• Rotational Grazing of Alfalfa with Yearling Cattle

[top] Effect of Flies on Grazing Behavior

Research at University of Kentucky has revealed that cattle modify grazing strategy in response to flies. Face flies, which feed on bodily secretions, congregate about the eyes and nostrils. Determent actions are largely limited to ear and head movements and are not particularly effective. Grazing cows thrust their nose into the pasture apparently using the leaf blades to swat flies off the nose and from around their eyes. Cows take bigger bites when they do this and this means they graze faster in the presence of face flies.

Stable flies, which are biting flies that feed on blood, like the legs because the blood vessels are close to the surface. Front legs are preferred to hind legs by stable flies because the tail very effectively sweeps flies off the hind legs. When stable flies attack the front legs, cows respond by lifting and stomping their legs, by localized skin twitching, by throwing their heads toward the legs and by flight. These actions obviously interfere with grazing. In the study at UK, flies lowered the cow's rate of biting from 46 bites per minute to 21 bites per minute. This effectively cut in half the rate of herbage intake and, as a consequence, cows had to graze longer each day to meet their needs or get by on less.

[top] The Cost of Fertilizing Pastures - by Clif Little, OSU Extension Agent

The cost of commercial fertilizers has risen dramatically since last year. Many forage producers are asking how much can I invest in my fertility program?

Locally we are currently paying:
Urea 46-0-0 $250/ton/bulk
Ammonium Nitrate 34-0-0 $285/ton/bag

The question becomes, with these prices can I afford to apply N when stockpiling a grass/legume stand? To put on 50 units of nitrogen at these prices it would cost:

Urea 108 lbs./ acre
18.51 acres/ton
$13.50/ acre
$6/ton spreading ÷ 18.51 = .324 spreading cost/A
total cost $13.82/acre

Ammonium Nitrate 147 lbs./ acre
13.6 acres/ ton
$20.95/ acre
$6/ton spreading ÷ 13.6 = .44 spreading cost/A
total cost $21.39/ acre

Can you recoup this cost when stockpiling? The answer to this question depends on what value you put the extra forage generated by stockpiling.

If hay is worth $30/ton then you would need to generate the following amounts of forage for the above-mentioned nitrogen sources.

Urea $13.82 cost/ Acre
$30 ton value
= .46 tons or 921 lbs./ Acre

Ammonium Nitrate
$21.39 cost/ Acre
$30 ton value
= .7 tons or 1400 lbs./ Acre

In grazing or feeding forage a percentage of the roughage is wasted. We have not accounted for these losses. The more intensely you graze the more efficient you are at harvesting available forage. In addition, stockpiled forage (fescue and orchardgrass) has a higher relative feed value than the same unfertilized grass. Finally, can we produce this amount of forage with these nitrogen sources?

Stockpiling typically results in an additional 1000-2000 lbs. of dry matter/ acre. Since I'm not adjusting for dry matter we'll be conservative and say we expect an additional 1200 lbs. dry forage per/acre. If it costs $20/acre to obtain this level of production then:
$20 cost = $33/ton
.6 tons of forage is the breakeven

If we value this extra forage at $33/ton then the practice will pay off. If we can purchase comparable forage significantly cheaper then stockpiling becomes uneconomical. Again we have not adjusted for improved forage quality or labor, however, N application for stockpiling appears to be economical.

[Top] It's Not Too Late to Plan for Fall & Winter Grazing

Chris Penrose, Dave Samples, Clif Little
OSU Extension Agents

As autumn approaches and we are starting to get an idea on our winter feed supplies and the number of animals we want to keep into next year, it is a good time to assess the quality and amount of forages that will be needed. For many, corn and purchased hay can be a reasonable option, depending on local availability. For others, there is still time to stockpile pasture or hay fields, and plant turnips and winter rye for fall and winter grazing.

Stockpiling fescue and orchardgrass will cost the least money and require the least effort to extend forage supplies. Initiating the stockpiling (make the last clip or grazing) can be anytime through September. As a rule of thumb, the earlier you start (don't start before the middle of July), the more you will have, but the lower the quality. The opposite is also true: the later you start, the higher the quality, but a lower yield. The addition of 50 pounds of nitrogen when stockpiling begins will result in a 1000-2000 pound increase in yields. The only exception to this rule is where substantial amounts of clover are in the stand. Research shows little response to N application where the stand consists of more than 40% red clover.

The final results of stockpiling will be up to two tons of dry matter per acre, which will be available November through February. Quality can slowly drop after Thanksgiving then a little faster through February, but will usually be still good enough for a brood cow or ewe in good condition. Research conducted at OARDC Jackson Branch indicates that orchardgrass protein can remain 12% into February, but yields will fall off rapidly after prolonged cold temperatures, but fescue yields will hold up better.

Turnips and other brassicas are also options to extend the grazing season. Most turnip cultivars need to be planted from mid July through early August. Although it is starting to get late to plant turnips, the cultivar that will do the best when planted late is our garden type purple top turnip. Most cultivars need 60 days to reach maximum quality and 90 days to reach maximum yield. In studies in Southeast Ohio, purple top turnips reached maturity almost two weeks prior to other cultivars.

Several producers have mentioned how well turnips work when they are planning to renovate a field, because they can get an extra crop of turnips in the winter, prior to spring planting. Some have even broadcasted wheat or winter rye in October and had a crop the next spring. Ed Ballard, Extension Specialist in Illinois, has demonstrated that in Illinois turnips, oats and winter rye can be successfully broadcasted over standing crops such as soybeans prior to harvest for winter grazing.

To get a good crop of turnips, all you need is two pounds of seed per acre, fifty pounds of nitrogen, seed to soil contact, and rain to get the crop started. No-till and conventional seed beds both work. This is a crop that can produce 10,000 pounds of dry matter in ninety days with tops around 16% protein and bulbs around 9%. Brassicas are very low in fiber, so consider supplementing hay or stockpiled forages to improve utilization. The crop should remain available to livestock until temperatures fall below 15 degrees.

Winter rye is another option that can produce a high quality crop for grazing in December and March. What makes this such an attractive option, is that it is very high in quality and is the first to green up in the spring. This is a good option for livestock with high nutritional needs such as overwintering stocker calves. Winter rye can be planted from the middle of August through the middle of September at 90-100 pounds of seed per acre. When rye is 2-4 inches tall, 50-75 pounds of nitrogen will stimulate growth and additional applications in early March will increase production.

Any of these crops can stretch feed supplies and keep costs down, especially when stripped grazed with an electric fence. OSU Extension has fact sheets available on each of these crops which are available at your local Extension office or on the web at: http://ohioline.osu.edu/. Ask or look for: "Stockpiling Tall Fescue for Winter Grazing," AGF-023; "Brassicas for Forages," AGF-020;
or "Winter Rye to Extend the Grazing," AGF-026.

[Top] Rotational Grazing of Alfalfa with Yearling Cattle - by Roy Burris, James Randolph, Monroe Rasnake & Gary Lacefield, University of Kentucky

Alfalfa is generally thought of as a hay crop but the practice of grazing alfalfa has received much attention recently. Alfalfa's ability to withstand dry weather and its excellent nutritional qualities make it an attractive grazing alternative - especially during the midsummer period. Grazing also requires less equipment than conventional harvesting of hay. But it also requires intensive management for optimum results.

In Kentucky, a study was established to test a system of intensive grazing of beef steers on alfalfa to maximize gains and preserve the stand. The alfalfa was no-till seeded in a 16-acre field in the fall following corn silage. The field was divided into eight paddocks. Poloxalene for bloat protection was fed in about 2 lbs. ground corn per head per day. Each paddock was grazed four days.

Alfalfa was grazed the first year for 103 days and produced gains of 546 lbs./acre with an average daily gain (ADG) of 2.07 lbs. per head. Alfalfa was grazed the second year for 117 days with

gains of 477 lbs./acre and ADG of 1.61 lbs. per head. Steers grazed alfalfa 152 days during the third year and gained 732 lbs./acre with ADG of 1.31 lbs. per head. The alfalfa stand declined some by the end of the test, but no more than would have been expected in a hay system.

Results of the 3-year study indicated that:
1. Alfalfa can support excellent gains for yearling beef cattle.
2. Bloat can be controlled with daily intake of poloxalene.
3. Temporary electric fence can be used effectively.
4. The alfalfa stand persisted after 3 years of intensive grazing.
5. Best results were obtained by removing the heaviest calves midway through the grazing period and replacing them with lightweight calves.

Editor's Note: While any alfalfa variety can be grazed with careful management, varieties with improved grazing tolerance are now available. Results of university trials on alfalfa grazing tolerance are available at the following websites:
http://www.public.iastate.edu/~brummer/extension.html
http://www.ca.uky.edu/agc/pubs/pr/pr438/pr438.htm

All educational programs and activities conducted by Ohio State University Extension are available to all potential clientele on a nondiscriminatory basis without regard to race, color, creed, religion, sexual orientation, national origin, sex, age, handicap or Vietnam-era veteran status. Keith L. Smith, Associate Vice President for Ag. Admin. and Director, OSU Extension. TDD No. 800-589-8292 (Ohio only) or 614-292-1868.

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.

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