A bi-monthly news publication of The Ohio State University Extension, Editors: Clif Little and Mark Sulc
This newsletter is made possible with support from the Bob & Jewell Evans Foundation
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Contents:

• Analyzing your Forage
• Grazing Corn Residue
• Winter Supplementation of Beef Cows
• Grazing Loses a Great Supporter

[top] Analyzing Your Forage - Clif Little, Extension Educator, Guernsey County

Forage quality changes with maturity and storage. A forage test can supply useful information about the nutritive value of hay or pasture. This information can be used to adjust the amount of supplement fed. If forage quality is high, the producer can feed less supplement, resulting in savings. Conversely, if the forage quality is low, diet supplementation can improve animal performance, and increase profits. This article discusses how to take a forage sample and how to interpret the laboratory results.

Taking a forage sample
Forage test forms can be obtained from your county Extension office or from the website of the lab you plan to use. These forms contain complete instructions on how to collect forage samples. Proper collection and identification of a sample is very important. A tool is needed to collect hay samples. Your local Extension office may have a Penn State Forage Sampler or similar device. A hay sampler consists of a long tube with a cutting edge on one end and a shank on the other that can be fastened to an electric drill or hand brace.

1. To correctly sample a rectangular bale, the bit is driven into the end of 18 to 20 bales from a particular lot of hay. Drill to the full depth of the sample tube on loose bales and half depth in tight bales. Mix the cores thoroughly and send the entire sample to the lab in a sealed plastic bag.


2. Large round bales should be sampled on the rounded side of the bale. Collect a single sample from each of 10 to 12 bales from the same lot, combining the core samples into one sample for analysis. If the outer layer of the round bale is weathered, pull away 1 to 2 inches and sample underneath. Drill to the full depth of the tube.

Your hay should be segregated into lots, each lot representing a fairly uniform population of hay. For example, each hay type and cutting should be sampled and analyzed separately. Hay harvested on different dates within a cutting or even from different fields should also be sampled separately. Therefore, it is important that each cutting is stored separately and can be identified with its forage test. When sampling forages one cannot over stress the importance of proper sampling technique. Samples should be representative and selected at random. In summary, sample each lot of forage separately, and make sure that the forage can be identified with its analysis when feeding.

Silage can also be analyzed. To sample silage, run the unloader and collect from the feed bunk in 5 to 6 places. Put four handfuls of silage into a plastic bag. Collect samples for two or three days, then mix thoroughly and subsample 1 to 2 pounds. Keep samples in the refrigerator during the collection period and store them in a plastic bag. Seal the bag, attach a completed tag and mail immediately or freeze and mail the frozen sample to the laboratory.

Bagged silage can be sampled by cutting slits along the side of the bag in 5 to 6 places. Collect handfuls and mix in a clean plastic bucket. Mix well and bag in plastic with a tag. Reseal the slit with heavy duty tape.

Silage can also be sampled while it is going into the silo. Collect representative samples from each wagon as it is unloaded and mail immediately or freeze the samples. Take the same number of samples from each wagon and keep them in a container. If the silage lot changes (i.e., a particular hybrid, field, area of the farm), start another container. When all samples have been collected, mix the sample within each container, and collect a random 1 to 2 pound subsample for analysis. Seal in a plastic bag and send to the lab immediately or freeze if they can't be mailed promptly. Fresh silage samples are a good way to plan your feeding program. However, it is a good idea to sample silages when they are being fed and have gone through the fermentation process.

Pastures can be sampled by collecting pasture grass at the height animals are grazing. Collect random grab samples of forage from several locations. Air dry the sample if possible, before sending to the laboratory. This can be done by hanging the forage inside a burlap bag for about a week. Fresh samples should be mailed immediately. There are many reasons to forage test. If you are considering testing your forage, most forage testing labs can provide forage or feed analysis.

Interpreting Lab Test Results
Let's say you have sampled four lots of different hay. Let's take a look at some typical lab results. Table 1 shows samples taken from hay produced on a farm in Guernsey County. These samples were all harvested in mid- to late June.

Now that we have our results, how do we use them and what do they mean? As a hay producer you probably have a similar scenario, several lots of hay, each with a different nutrient composition. Let's go through our report and look at the differences between each nutrient and finally determine how we might use these forages. As we consider the nutrient levels in our hay we should consider the animal's sex, weight, daily gain, stage of production, and environmental conditions.

The analysis of these forages has indicated that only one sample (158) can meet most of the nutrient requirements for our cattle. The three other hay sources will need to be supplemented with a protein source and mineral supplement. Our good quality hay should be used for cows requiring an improvement in body condition or lactating and growing animals.

Analyzing your ration will save you money and help to ensure the nutrient requirements of your cattle are being met. Almost all forages should be provided with access to trace mineralized salt. Hay quality is most affected by maturity. Early harvest and pasture rotation before seed heads appear will greatly improve the quality of your forage. Forage quality can vary significantly and so can the nutrient content of your forage. A forage analysis can help you evaluate the nutritive value of hay when buying and selling hay. Without this analysis is will be difficult to correctly determine your winter supplementation program. For assistance with your forage analysis, contact your local Extension office.

[top]Grazing Corn Residue- Dave Samples, Extension Emeritus, and Jeff McCutcheon, Extension Educator, Knox County

Within Ohio, more than three million acres of corn are harvested each year. Most of those acres are harvested for grain with the remaining plant parts redistributed on the soil. In addition to the value of the grain, one acre of corn residue can supply enough forage to sustain a 1,000-pound cow or animal equivalent for 1.5 to 2 months.

Considering that Ohio's beef herd consists of more than 280,000 head, enough feed is going out the back of combines to feed the total cow herd in Ohio for at least 16 months. Snow, mud, and the need to plant next year's crop make that calculation unrealistic, but there is enough feed remaining on corn fields after harvest to significantly increase the grazing days for ruminant livestock.

Livestock producers do not take advantage of this vast feed resource for various reasons, such as: the location of the animals in relation to the harvested fields, lack of fencing and water supply, and concerns about compaction and residue compliance for conservation programs. In spite of these obstacles, grazing corn residue can be an important part of many livestock operations. The use of corn residue offers producers increased flexibility for fall and winter pasture and helps reduce the overall feed costs.

How Much Forage Can I Expect?
Half of the weight of the total corn plant is residue left after harvest. This residue consists of stalk, leaf, cob, and husk. The stalk, which is typically the last plant part consumed by livestock, contains the most moisture and is one-half of the dry matter weight of the total residue (Table 1).

It is estimated that for each bushel of shelled corn produced per acre, 50 pounds of residue are also produced. At that level, an acre yielding 120 bushels of corn will produce 6,000 pounds of residue. An added benefit for grazers is that corn grain is also lost in the harvesting process. It is estimated that at least three bushels of grain per acre are left on the field during harvest. This means that more than 150 pounds of corn per acre are also available for the animals to consume.

How Good Is the Residue?
Corn residue is not a high-quality feed (Table 2) and would not be adequate for growing animals or maintaining producing females year-round unless supplemental feed was provided. However, if grain is available in the residue, then the consumed feed quality may be adequate for some stages in the livestock production cycle (Table 3). The feed quality of corn residue is lower 60 days after harvest, indicating some weathering and loss of nutrients. The greatest loss is from deterioration of the husk and leaves, while cobs and stalks less affected. Rain can accelerate the decomposition process. Also, snow cover will limit an animal's ability to find the smaller plant parts, further limiting the quality of feed available.

How and When Should Livestock Graze?
Corn fields should be used immediately after harvest for 30 to 60 days to take maximum advantage of the feed value of the residue. This would allow the permanent pastures to "stockpile" additional days of fall growth that could be grazed after the animals come off the corn fields. Grazing corn fields for an extended period, even all winter, is also an option if supplemental feed is provided and the fields remain dry.

Livestock will selectively graze the most palatable portions of the residue first, starting with the grain, leaves, and husks and then the cobs and stalks. Generally, animal grazing will leave 75 to 80% of total residue in the field, especially if animals are rotated to new areas before much of the cob and stalk material is consumed. With this in mind, one acre of corn residue will yield approximately 60 animal-unit grazing days. This means that one acre of corn residue will provide 60 days of grazing for a 1,000-pound animal, or 30 days for two animals.

Limiting access by strip grazing will allow for an increased stocking rate and greater utilization of the residue. This can be accomplished by using portable electric fencing. Either a single break wire to the front, or double wires with one in front and one behind can be used effectively, depending on the layout of the field and water sources. However, if strip-grazing practices are used, and snow cover arrives before the field is grazed through, some of the best feed may be lost if the grain and husks cannot be recovered.

The easiest fit for grazing crop residue is with non-lactating, mature beef cows or ewes that are in the middle trimester of gestation and are in desirable body condition. Animals that have grain to select will consume a diet that is probably above 7% crude protein and as high as 70% Total Digestible Nutrients (TDN). If corn is visible in the manure, supplementation with anything other than vitamins and minerals is probably not needed. However, when most of the grain has been consumed, or little grain was left in the field, protein supplementation will probably be needed. Several studies have shown that dry cows will at least maintain body weight and may gain up to 1.0 pound per head daily while grazing corn stalks that have grain, husk, and leaves to select.

For other classes of livestock such as first-calf heifers, ewe lambs, fall-calving beef cows, lambs, and calves will require supplementation when grazing corn residue. Those classes of animals have higher nutritional needs than average corn residue can provide, and producers cannot afford to ignore those needs.

For more information check out the factsheet "Grazing Corn Residue", ANR-10-02 http://ohioline.osu.edu/anr-fact/0010.html

[top]Winter Supplementation of Beef Cows- Clif Little, Extension Educator, Guernsey County, Stephen Boyles. OSU Extension Beef Specialist

Protein Supplements
Protein supplements can increase low-quality forage digestibility and intake while extending the grazing season. Limited amounts of high-protein supplements greater than 30 percent crude protein (CP) can be used with low-quality forages (less than 8 percent crude protein and 45 percent total digestible nutrients [TDN]). High-concentration protein supplements that are natural protein sources do not need to be fed every day. Simply feed twice as much every other day. When forage is of 8 to 10 percent crude protein content, a 20 percent crude protein supplement can be fed daily. Protein supplements containing nonprotein nitrogen can be used, but only in limited amounts, and should be provided on a daily basis. The prices utilized in these calculations will vary between sources. Use these formulas by substituting in the correct price and nutrient value of your supplements.

Cost of Protein Supplements
A simplified method of determining cost per unit of crude protein follows:

Soybean Meal, 50% Crude Protein (as fed) at $236/ton:
2,000 lb. soybean meal x 0.50 = 1,000 lb. crude protein
$236/1,000 lb. = $0.24 cost per pound of crude protein

Cottonseed Meal, 41% Crude Protein (as fed) at $230/ton:
2,000 lb. cottonseed meal x 0.41 = 820 lb. of crude protein
$230/820 lb. = $0.28 cost per pound of crude protein

These calculations illustrate the importance of comparing the cost of protein when considering the purchase of a protein supplement. Producers may also want to consider the mixture of protein being provided. These calculations don't consider concentrations of rumen degradable protein and "bypass" protein sources. For proper rumen function, a portion of the dietary protein must be degraded in the rumen for microbial growth, and the rest can be absorbed later in the digestive tract. Providing a mixture of microbial protein and bypass protein will maximize animal production. Low-bypass protein sources include casein, soybean meal, sunflower meal, and peanut meal. Medium-bypass sources include alfalfa meal and brewers dried grains. High-bypass sources include meat meal, corn gluten meal, feather meal, fish meal, and formaldehyde-treated proteins.

Value of Supplements
The previous example of cost per unit of crude protein is only part of the information when determining which supplement to use. Other considerations are availability of the supplement, feeding method, time required to feed, and service provided with the supplement.

Typically cubes, cakes, blocks, and tub supplements may have a higher cost per unit of nutrient supplied. However, they can be easier to feed and require less daily management. A meal- or pelleted-based supplement may require feed bunks to effectively provide the supplement to cows whereas cubes, blocks, and tubs are ready to feed and do not require a feed bunk. Distance from the cows also needs to be considered. Blocks and tubs can remain with the cows whereas a bag supplement must be transported to the cows on a fairly regular basis.

Supplements developed by feed companies often will contain additional minerals, vitamins, and selected feed additives. Simply calculating cost per unit of a single nutrient fails to take into account the benefits of these added products.

Selecting an Energy Supplement
In many cases, our forages may be adequate in protein to meet the requirements of gestating cows but may lack sufficient energy. Energy units may be Total Digestible Nutrients (TDN), Net Energy Gain (NEg), and Net Energy Maintenance (NEm). Price per unit of nutrient will vary within the same feed depending upon the unit you use for comparison. Grain usually contains a readily available starch. Grain sugar and starch ferments rapidly in the rumen and may lower rumen pH, resulting in reduced feed intake and digestibility of forages. It is therefore recommended that the amount of grain be limited when used in a forage-based diet. Certain feeds such as soybean hulls, corn gluten feed, beet pulp, and brewers grains are satisfactory energy sources, but the starch is more slowly degraded and does not alter rumen pH to the same degree as grain sources such as corn.

Comparing the cost of TDN, we can estimate the cost of energy supplements as we have done for protein supplements in the previous example.

Hay valued at $60/T with 50% TDN
$60/20 (100 lb. increments) = $3 per 100 lb. hay
$3/0.50 (% TDN as fed) = $6.00 per 100 lb. TDN

Corn valued at $70/T with 80% TDN
$70/20 = $3.50 per 100 lb.
$3.50/0.80 (%TDN as fed) = $4.38 per 100 lb. TDN

Soybean hulls valued at $85/T with 70% TDN
$85/20 = $4.25 per 100 lb.
$4.25/0.70 (% TDN as fed) = $6.07 per 100 lb. TDN

Like protein sources, energy sources also vary amounts of minerals and vitamins available. For this reason, it is important to consider the cost per unit of nutrient along with the ease of handling, amount of concentrate fed, forage quality, and type. In addition, protein and energy sources that differ significantly in dry-matter content should be adjusted and compared on a dry-matter basis. For these calculations, we have used (as-fed) values for crude protein and Total Digestible Nutrients. If we had utilized book values, based on a 100% dry-matter basis, we would simply divide the cost per unit (CPN, TDN) by the percent dry matter (decimal value) of the feed ingredient.

Shop for the nutrients you need this winter. Comparing the price per unit of nutrients you need can help you put an economic value on the feed. Yet another important factor in determining the correct supplement is the methods of feeding and method of storage.

For more information check out the Factsheet "Winter Supplementation of Beef Cows", AS-1-99, http://ohioline.osu.edu/as-fact/0001.html

[top]Grazing Loses a Great Supporter- Clif Little, Extension Educator, Guernsey County

This past June the national media published stories of the passing of Mr. Bob Evans. The articles chronicled Mr. Evan’s life and restaurant business development. This very newsletter however was staunchly supported by Mr. Evans. Mr. Evans covered the cost of postage and mailings, making it possible for this newsletter to go out free of charge to hundreds of recipients.

However, this was not the only contribution Mr. Evans made to grazing. Mr. Evans sponsored many trips to grazing conferences. He would help to cover the cost of transportation and hotels for Ohio farmers when attending educational events. In addition, Mr. Evans gave to support forage related research projects. He also sponsored the publishing of educational materials utilized in grazing schools. He personally hosted grazing educational programs at his own farm while demonstrating innovative techniques on rotational grazing and the use of alternative forages.

Mr. Evans believed in the small farm and efficient grazing practices. He felt by making efficient use of existing forages, livestock producers could be competitive.

I for one will never forget Mr. Evans’ unselfish contributions to many Ohio farmers. The thousands of Ohio livestock producers attending grazing schools and conferences over the last twenty years may not have known Mr. Evans was contributing to their education. He did not insist that his name or his contributions be highlighted. Mr. Evans was very sincere in his love and hope for Agriculture. I doubt that I will ever again see a man as generous as Mr. Evans.

Thanks Bob.