November 9, 2015 Comments are off Montana Stockgrowers Association
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Forage Considerations For Fall Grazing

From “Pastures for Profit: A guide to rotational grazing”. University of Wisconsin Extension. 2014.

From “Pastures for Profit: A guide to rotational grazing”. University of Wisconsin
Extension. 2014.

By Dr. Emily Glunk, MSU Extension Forage Specialist and Assistant Professor

There are a lot of questions regarding whether or not it is safe to graze your fall pasture, and to what extent. Fall is a tricky time to manage grazing on pastures, as there is a lot going on with the plants below-ground, which we can’t always see. Grazing too hard in the fall has the potential to be very detrimental to forages, and should be managed accordingly.

So what all is happening right now in our forages? Cool-season grasses are trying to grow more new roots to replenish those that had been shed earlier in the summer. Right around June 21, the summer solstice, a lot of our introduced cool-season grasses shed their roots and begin to grow new ones, contributing to what is known as the “summer slump”. If you trek out to your pasture and dig up a couple plants, you should see quite a few new white roots and tillers forming, indicating a healthy plant and a healthy stand. Our legumes don’t shed their roots, as they have one well-defined taproot, but they are trying to store up enough carbohydrates to serve as any energy source for regrowth in the spring.

It is important that we don’t graze our pastures too heavily in the fall, as we can significantly impair the plants ability to store carbohydrates, or energy, which will help in the regrowth and recovery process. Plants go through a process called photosynthesis, which transforms sunlight into a usable energy source. The plants ultimately convert the sunlight (in the form of photons) to carbohydrates, which are stored in the roots or lower parts of the stem in some grasses. By grazing heavily, and removing most of the leaf area which is required for photosynthesis, we are limiting the plants ability to capture sunlight, and therefore create and store energy. This will be evidenced by slow growth in the spring, creating an opening for weed invasion, or if bad enough, winter kill over the winter.

So what can we do to manage these plants and prevent this from happening? Number one is to not graze very heavily in the fall. Allow those plants enough leaf area to continue photosynthesis, while not trying to use too much of their carbohydrate reserves for regrowth prior to winter. That is not to say don’t graze at all, but try to maintain an adequate stubble height for those forage species. You can contact myself or your local county agent to get species-specific recommendations. Number two, you can wait until after the plant has gone dormant to graze it down lower, because at this point the plant is no longer going through photosynthesis and accumulating carbohydrates, and it will no longer be using its energy reserves for regrowth before spring. You still should take care and be mindful of the impacts of hoof traffic on plant roots, especially in muddy conditions. While the plant may be healthy and have plenty of carbohydrates, if the animal physically injures the plant or its roots, this too can have a negative impact on regrowth ability and plant survival.

From the figure below, we see that carbohydrate reserves are at their lowest around internode elongation phase, a time when we have to be very careful in our management. This is when reserves are being used for primarily for plant regrowth and leaf production. Once there are enough leaves present, and the plant has begun the stem elongation phase, we see an accumulation of carbohydrates. The plant will be able to start storing carbohydrates at this point for regrowth in the spring. We want to make sure that the plant has the ability to store enough carbohydrates before a killing frost, so that we don’t see a problem in the spring.

Another thing that we see happening in the fall is the development of growing points for next spring’s growth. Those are the tillers that we can hopefully see when we dig up some plants. Old tillers may appear brown and dead, but they still serve an important role to the plant. They are a form of stored nutrients, as well as provide protection to the new, developing tillers. We also want to avoid allowing animals the ability to graze off these new tillers, which will be helped by leaving adequate stubble height. Another benefit of leaving some stubble in the field is that it increases the amount of snow that is caught, insulating the soil, and decreases the potential for ice sheeting. This too will help increase plant survivability over the winter.

For any questions or forage recommendations, contact Dr. Emily Glunk at [email protected] or 406-994-5688. or contact your local county extension agent.

September 1, 2015 Comments are off Montana Stockgrowers Association
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Watch for Nitrate Toxicity in Forages

Emily Glunk Montana State Forage ExtensionBy Dr. Emily Glunk, MSU Extension Forage Specialist

Nitrate toxicity is a problem that many producers have to deal with in Montana. Particularly this year, with a large amount of cereal grains being harvested for hay, it is something that should be kept in the back of your mind at harvest and feedout.

Nitrate toxicity is an accumulation of nitrates in the plant. Typically, the lowest third of the plant stem will have the highest level of nitrates. Why are these high levels of nitrates toxic to the animal? When the animal consumes a large amount of nitrates, it is unable to be completely converted to microbial protein in the rumen. Instead, an intermediate in the conversion of nitrate to protein, nitrite, will be transported to the small intestines and absorbed into the blood system. This is where the real problem starts. Nitrite will bind to hemoglobin, the oxygen carrying component of blood, to form methemoglobin. Methemoglobin is unable to supply oxygen to the rest of the body, and the animal will start to become stressed.

Acute toxicity signs include things such as labored breathing, muscle tremors, weakness, and ultimately death. Animals that have chronic toxicity, or have been consuming high levels over a long period of time, will have decreased production, rough hair coat, and reproductive issues, among others.

What is happening in the plant to cause increased nitrate levels? Nitrate accumulation can occur for many reasons: environmental stress such as drought or hail, excessive application of Nitrogen fertilizer, deficiency of other nutrients such as K and S, shade, prolonged cool temperatures, the list goes on. Another important factor is plant species. Cereal grains tend to accumulate nitrates more-so than cool-season forages. Oats have been found to be the most prone to accumulating toxic nitrate levels, with wheat and barley a little less likely. Warm-season grasses such as sorghums and sudangrasses also have potential to accumulate nitrates.

If any of these situations occurs, or the plant becomes stressed, the likelihood of accumulating toxic levels is increased. In most of these situations, photosynthesis is inhibited or decreased, which supplies the Carbon, or energy, that is required to convert the nitrate to plant protein. Without the required Carbon, similar to in the rumen, the nitrate will not be converted to the final, desirable product, protein.

How can we decrease the chances of nitrate toxicity? There are a few things that we can watch out for. Always make sure that you are monitoring soil nutrient levels, and try to apply fertilizer according to soil and plant needs. Make sure to not overlook other soil nutrients, like Potassium and Sulfur, as they can have a significant impact on Nitrate uptake and accumulation in plants. Take care when applying and handling any N fertilizer, so that large amounts don’t get spilled or over-applied in one particular area. When harvesting, wait for several days after a drought-ending rain before harvesting, or after a hail event.

If you suspect your forages may be “hot”, I would advise to test them before harvesting or feed out. Your local county agent has an in-field test called the Nitrate QuikTest, which allows them to qualitatively estimate whether your forages may have toxic levels or not. This test does not provide a level of nitrate, but rather advises you as to whether there may be toxic levels or not based on what color the testing solution turns, and how rapidly that change occurs. We are also looking to test some in-field quantitative nitrate testing kits, to evaluate whether these commercially available products are accurate and reliable ways to determine nitrate levels in standing forage.

If your forage tests hot, or may be marginal, I always recommend sending it in to a lab for a quantitative nitrate analysis. This will help you determine if you need to dilute the hay in the ration by feeding it with a low-nitrate forage, or if it is safe to feed. Toxic levels also depend on production stage of the animal, with young and pregnant animals having low tolerance to nitrates, as depicted in the table below. You can contact your county agent, or myself, to help develop a ration that is suitable to feed to your animals.

If you have any questions or comments, please contact Dr. Emily Glunk at 406.994.5688 or at [email protected]. For more detailed information on nitrate toxicity, you can also reference the Montana Extension MontGuide “Nitrate Toxicity of Montana Forages” (MT200205Ag).

July 20, 2015 Comments are off Montana Stockgrowers Association
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How Much Seed Should I Plant?

Emily Glunk Montana State Forage ExtensionDr. Emily Glunk, Extension Forage Specialist and Dr. Jessica Torrion, Crop Physiologist

Depending on who you ask, you may get a wide range in how much seed you should be planting per acre. There are a lot of factors to consider, but in my experience, there are many producers throughout the nation that are spending more money, and putting more seed in the ground, than is necessary. There are some situations where it may be desirable to increase your seeding rate, say in an irrigated field versus a dryland field, if the seedbed is less than optimal, or where the seeding depth is hard to get completely accurate due to rough terrain.

It is important to remember that not every seed that is dropped will result in a plant. This is where your seed tag can be helpful. On the seed tag, it should list a germination percentage. This is an estimate of how many of the seeds in that bag are actually viable and able to germinate. Also important on the tag is the list of other potential “contaminants”, such as weed seeds (which will be listed as a percentage), other seed, and inert matter. The percentage of each of these should be minimal.

Another factor that can decrease germination rates is the seeding rate itself. Research from other states has found an estimated 45% mortality rate in the first year for alfalfa planted at 10 pounds per acre, and a 60-70% mortality rate for seeding rates over 20 pounds/ acre. So having a high seeding rate can actually be detrimental to your seed!

The important thing to start with is how many plants do you need per square foot? This will then help you to calculate how many pounds of seed you will need per acre. There are many tables available which provide estimates of desired number of plants per square foot. Alfalfa, for example, 30 plants per square foot is an optimal target plant population. Now, that does not mean that every year thereafter we are expecting to have 30 plants per square foot. Competition amongst plants for nutrients, canopy space, and water will decrease that number to less than 20 plants per square foot just after the stand’s first winter.

There are approximately 199,000 alfalfa seeds in one pound of seed, which equates to about 5 seeds per square foot if that pound were spread evenly over an entire acre. So, to figure out how many seeds you are planting an acre for alfalfa, take your seeding rate (in pounds per acre), and multiply by 5. If you were planting at 8 pounds of Pure Live Seed (PLS, we’ll cover that later), that means that you are putting approximately 40 seeds per square foot. Will you see 40 plants per square foot? Likely not. Seeds will also compete with one another, just like germinated plants, for light, moisture, and nutrients, and the most competitive plants will survive.

How can we figure out then how many pounds of seed we need to put in the ground? Let’s first get back to that thing I mentioned before, pure live seed or PLS. This is the amount of seed that has the ability to germinate, and is what we should be using when we are considering how much to plant. To figure this out, we simply use the information provided on the seed tag.

seed tag how much to plant

Step 1. We first want to figure out the purity of the seed in the bag. To determine this, we simply subtract the percent other crop, percent innert matter, and percent weed seed from 100.

For this tag, it would look like:

100-.11-.69-.18= 99.02% purity.

As you will notice, this number is already on the seed tag, however, not all seed tags will list this.

Step 2. Next, we need to determine PLS by multiplying that percent purity by the percent germination, and then by 100 as a conversion factor. Also remember to convert your percent’s to decimals, so 99.02% would be .9902.

.9902 (% purity) * .93 (% germination) * 100= 92.08% PLS

You will notice the percent germination was not actually listed on the bag, but we were able to figure it out by dividing the PLS weight (2.79 pounds) by the bulk weight (3 pounds).

Step 3. To figure out how many pounds of PLS we would need to get our desired establishment rates with this bag, we would then divide the recommended seeding rate (usually listed on the tag, for this we’ll use 10 pounds).

10/ .9208 (PLS in decimal form)= 10.9 pounds required at seeding

For this particular bag, there was very high germination rates and low levels of foreign seed, so we didn’t have to increase our seeding rate that much to get the desired number of seeds in the ground. This may not always be the case, which is why knowing how to figure out your PLS rate is extremely important to attain adequate stand establishment.

One final note, just like any other crops, seed size can influence the number of seeds per pound. Bigger seeds means less seeds per pound, and smaller seeds mean more seeds per pound. This is something to be mindful of, and to ask of your seed dealer, when purchasing seed.

For a list of recommended seeding rates, contact myself, Dr. Jessica Torrion, or your local county extension agent. There are also numerous publications available with seeding rate recommendations, such as the “Dryland Pastures in Montana and Wyoming”.

If you have any questions or concerns, please feel free to contact Dr. Emily Glunk at 406-994-5688 or [email protected], or Dr. Jessica Torrion at [email protected]

May 18, 2015 Comments are off Montana Stockgrowers Association
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Importance of Soil Testing Livestock and Hay Pastures

Image via: nrcs.usda.gov

Image via: nrcs.usda.gov

By Dr. Emily Glunk, Montana State Forage Extension Specialist

I get a lot of questions on the importance of soil testing, and if it’s worth it. My answer: yes.

A soil test can give you a lot of very helpful information that can help in your forage production, for a relatively small amount of money. I like to use the comparison of feeding your livestock to feeding your forages. When we develop a ration for our cattle, we make sure that they are meeting their energy, protein, vitamin and mineral needs so that they can perform to the best of their abilities. Why wouldn’t we do the same for our forages? By neglecting to ensure that there is sufficient Nitrogen (N), Phosphorous (P), Potassium (K), Sulfur (S), etc. in our soils, we are decreasing that plant’s ability to produce to its maximum potential, also decreasing the amount of nutrients that it can supply to the foraging animal.

The first thing I always ask when people look for advice on forages to establish is “what is your pH?” This piece of information is so important, and can save you a lot of time, money, and headache down the road. However, the only way to accurately estimate this is by performing a soil test.

The pH of a soil is important for a couple of reasons. 1. It gives you an idea of whether or not a species will be able to establish in your soils. For example, sainfoin does not particularly like acid soils, so if your pH comes back at a 6, then you may have some issues getting sainfoin seeds to germinate. And 2. It gives you an idea of the availability of the nutrients in your soil

Not every nutrient is going to be highly available at every pH. Macronutrients, such as Nitrogen, Phosphorous, and Potassium are usually more available to a plant at a more neutral to alkaline pH, or a pH greater than 7. Micronutrients like Iron (Fe), Copper (Cu), Molybdenum (Mo), and Manganese (Mn) are typically more available at slightly lower pH, say around 6. Knowing this helps us to cater to the soils, and provide adequate amounts of necessary nutrients for plants.

Image via extension.org

Image via extension.org

Soil tests will also give us an idea of how much of a particular nutrient is already in the soil. This will help us in developing a fertilizer regimen, and potentially save us some money in the long term. Instead of applying the same amount of fertilizer year after year, which may or may not be needed in that particular amount, we can provide only what is necessary to produce a healthy plant.

Nutrients will differ in how long they “stick around” in the soil. Nitrogen is a highly mobile nutrient, and fertilizing annually (if recommended from the test) is usually appropriate. However, because it is highly mobile, we don’t want to over-fertilize, which can lead to nutrient leaching, and wasted money on fertilizer. Nutrients such as Potassium and Phosphorous are relatively immobile, and usually are in the soil for longer periods of time after fertilization. In fact, if a stand is deficient in Phosphorous, and adequate amounts of P are applied, you may not see a huge increase in yield or quality until up to a year after that first application, due to its slow release.

When soil testing and fertilizing, don’t forget to look at the micronutrients. While needed in much smaller amounts that the macronutrients, these can play just as important of a role in forage production and quality. Things like Selenium (Se), Boron (B), and Manganese (Mn) can all be limiting to plant growth if they are in too small of amounts, or too large of amounts as well. With Boron, for example, it can be easy to surpass sufficiency needs and enter into toxic levels of applied B. Soil testing is extremely important in determining exactly how much your plant needs so that you can feed it properly. To help in developing these recommendations, Montana State University Researchers are looking into fertilization guidelines, and have developed several publications, with more still on the way. Most can be found on my website (http://animalrangeextension.montana.edu/forage/) or on the other Extension specialists’ websites as well.

For more information on how to soil test, or if you have any questions, please contact Dr. Emily Glunk at 406.994.5688 or [email protected].

March 16, 2015 Comments are off Montana Stockgrowers Association
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What’s the deal with sainfoin?

Emily Glunk Montana State Forage ExtensionBy Dr. Emily Glunk, Montana State Extension Forage Specialist

I have been getting a lot of questions on my travels around the state about sainfoin (Onobrychis viciifolia), and how can it fit into forage production in Montana.

Sainfoin is a legume, with a bright pink flower (although they can also be white or purple), and leaves with 11-21 leaflets. It may grow a little taller than alfalfa in certain environments, but a lot of times we are seeing similar production results.

One of the biggest benefits of sainfoin is that it is a non-bloating legume, which means that not only is it valuable in hay production, but we can also safely graze our livestock on it without having to worry about any bloat issues. In addition, because it is a legume, it is providing Nitrogen back to the soil via nitrogen fixation, which is a huge benefit and a large reduction in cost. Because let’s face it, the cost of fertilizer these days can be a little hard to swallow. When we add sainfoin, or other legumes, in a mixture with other grasses, we can significantly reduce or eliminate the amount of Nitrogen that we need to apply (however, soil samples should always be taken to know exactly how much we need to fertilize and with what).

We also know that sainfoin is very palatable. I have even heard it described as being “too palatable” (if you can imagine that) with it being preferred by wildlife over alfalfa and other forages. It has been described as being slightly more drought-tolerant than alfalfa, although it likes a little higher average precipitation, typically over 14” of annual rainfall. However, some producers actually state that they have had better luck with sainfoin in dryland situations than alfalfa, although this may not always be the case. It also likes soils with a pH above 7, and it seems to prefer coarser soils, or calcareous soils.

Another huge benefit is that sainfoin does not exhibit the allelopathic, or autotoxic effect that we see in alfalfa. This means that when we have a declining stand, or one that is producing below our desired goals, we can interseed more sainfoin, or allow itself to interseed naturally. This is a huge benefit, as we don’t have to worry about completely renovating our stand.

Typically, we see sainfoin mature at a quicker rate than alfalfa. One study found that sainfoin reached full maturity (100% bloom) while alfalfa was only at 78% bloom.

The same study also recommended that for the highest yield of both dry matter and nutrients that you harvest when sainfoin is closer to full maturity, a little different than that of alfalfa. We do see slightly lower crude protein values when the plants are compared at similar maturities, but they have similar TDN (total digestible nutrients) concentrations, and in some cases the NDF and ADF (see previous column, “The case for RFQ” for an explanation) were actually lower in the sainfoin compared to alfalfa. Because sainfoin is able to retain its lower leaves better than alfalfa, we see a slower decline in nutrient quality through the growing season, another added benefit.

Another interesting thing about sainfoin is that it seems to have a natural resistance to glyphosate (Roundup). This does not mean that it won’t have significant yield reductions like RoundUp Ready alfalfa  after glyphosate application, but when varying rates of glyphosate were applied to a stand of sainfoin over two years in Wyoming, the stand was able to survive glyphosate application. However, it should be noted that it did have a significant reduction in yield. Even glyphosate applied at a rate of 8 fluid oz. per acre resulted in a significant yield loss. However, the stand was able to recover the following year after in the low-rate treatments. So while it may potentially be a tool for weed control, it should not be a first resort.

So what are the drawbacks? Sainfoin can be finicky to get established, and it seems to take a little bit longer than other forages such as alfalfa. It also requires significantly higher seeding rates than alfalfa, which can prove costly. Also, when being grown in a mixture with many forage species, alternate seeding is more conducive to adequate stand establishment than a complete mixture.

This is especially important when it is grown with bunchgrasses like Russian wildrye and crested wheatgrass. Another limitation to establishment is that it does not like soils with high water tables, or soils that are poorly drained. We also recommend that you do not graze for two seasons after planting to allow it to get established.

Care should be taken when harvesting and grazing sainfoin so that there is still some leaf area remaining. Sainfoin does not store carbohydrates during the summer, and relies on photosynthesis for regrowth, hence the need for extra leaf area.

On average, we typically see alfalfa persisting for longer periods of time than sainfoin, but there are stands that are over 20 years old in Montana. The biggest problem that producers have is that it is a little more susceptible to root and crown rots than alfalfa, this typically being the reason that a stand needs to be terminated. But, especially in a rotational setting, sainfoin can be a great option to look at.

Overall, sainfoin is a great forage, with a lot to offer to Montana producers. If you have any questions or comments, contact Dr. Emily Glunk at 406.994.5688 or [email protected].

February 24, 2015 Comments are off Montana Stockgrowers Association
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The Case for Relative Forage Quality When Feeding Cattle Hay

Emily Glunk Montana State Forage ExtensionBy Emily Glunk, MSU Extension Forage Specialist

Feeding represents a large portion of the production and maintenance cost of animals. Some estimate that feeding can represent over 70% of the annual costs of maintaining a livestock herd, with hay representing a significant portion of that cost. Making sure that we are buying quality feedstuffs, and feeding in appropriate amounts, is critical in ensuring that we are being as economical as possible. In recent years, the cost of hay has increased significantly, and so efficient purchasing is critical.

A hay analysis is key in knowing the quality of the hay, how much to feed our animals, as well as being helpful in the buying process. Tools such as Relative Feed Value (RFV), which can be found on a hay analysis, have traditionally been used to compare hay. RFV uses fiber estimates, the acid detergent fiber (ADF) and neutral detergent fiber (NDF) portions of a hay analysis, to estimate the quality of the hay. This has been helpful in comparing between two types of similar hays, i.e. comparison of two alfalfa or two grass hays, however, it does not tell us everything about the availability of the fiber or other nutrients in that hay.

Several years ago, University of Wisconsin researchers developed a new method of comparison, called Relative Forage Quality, or RFQ. This value takes into account not only the fiber components of the plant, but the digestibility of those components as well. This tool is extremely helpful in telling us a little more about what may be available to the animal to use from that forage.

The ADF portion of a plant analysis is an estimate of the cellulose and lignin portion of the plants, cellulose being slowly fermented by the rumen or hindgut microbes before it can be converted into energy for the animal. Lignin is indigestible by both mammalian and microbial enzymes, and so is completely unavailable to the animal. Because it includes the parts of the plant that are relatively indigestible, ADF has been found to be negatively correlated to digestibility of plant material. This means that as ADF increases, digestibility of the plant decreases.

The NDF portion of a plant includes both cellulose and lignin, similar to ADF, but also includes hemicellulose, a fiber that is fermented more rapidly than cellulose by microbial enzymes in the hindgut or rumen. NDF has been found to be negatively correlated to intake, so as NDF increases, intake will decrease. This is largely a function of gut fill, so as an animal consumes a more fibrous feed, it will take less to fill up the gastrointestinal tract, thereby decreasing intake.

The problem with RFV is that it does not evaluate the availability of the nutrients. On average, a grass will typically have more fiber than a legume. However, the fibrous portion of grasses are  usually more digestible than the fibrous portion of a legume. Relative forage quality, RFQ, was developed to help account for that, using total digestible nutrients (TDN) in the calculations. This will be a better indicator of what is available to the animals and the microbes within that animal to use, and convert to energy. RFQ is typically going to be higher in grasses than the RFV value, while legumes may slightly decrease.

RFQ and RFV are also a great means of evaluating who got a “better deal”. Typically, if the RFQ ends up being higher than the RFV, then we say that the buyer got a better deal. This is because initially, with RFV, we may have thought that the forage was more indigestible than it actually it, which was shown in the RFQ. If the RFQ is lower than the RFV, we like to say that the seller got the better deal, as the forage was higher in indigestible fiber, so less is going to be available to the animal to use.

It must always be kept in mind that both RFV and RFQ are to be used only as a comparison between hays, its purpose is not to aid in ration balancing, but as an evaluation and buying tool. For any questions, please contact Emily Glunk, MSU Extension Forage Specialist, at 406.994.5688 or [email protected].

February 10, 2015 Comments are off Montana Stockgrowers Association
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Proper Winter Hay Storage

Emily Glunk Montana State Forage ExtensionBy Dr. Emily Glunk, MSU Extension Forage Specialist

There have been a lot of questions lately concerning how to properly store hay over the winter. The main goal with winter storage is to maintain quality and decrease any dry matter losses that we might incur. Minimizing exposure to the winter elements, especially precipitation which can decrease both hay quantity and quality, is our top priority.

Hay is the most common feeding option during winter, as it is less risky than other options such as stockpiling, and we know how much, or rather how long, our stores will last. However, not only is it important to have enough tonnage to support our herd, but also that we are maintaining the quality of our hay throughout the season.

The ideal storage for hay is inside, out of the elements, in a well-ventilated structure, whether this be a barn, shed, or a pole structure. Unfortunately, in Montana this is often not possible. So next we need to decide what are some other feasible methods of decreasing exposure to the elements. Leaving hay outside completely uncovered increases dry matter losses, ranging anywhere from 5-40% dry matter loss. Quality is also decreased, with some of the water soluble nutrients, like water-soluble carbohydrates, potentially leaching from the hay. This can decrease the overall energy available from the forage. Other components, such as nitrates, can move within the hay stack, and become concentrated in the lower bales, creating a potentially toxic feed for our animals.

Regardless of bale size and shape, it is advised to keep the forage off of the ground. Whether you stack it on pallets, fence posts, or even a well-drained gravel base, this will help to minimize loss. Storing bales on bare ground can cause an estimated 5-20% loss in dry matter, which can add up pretty quickly and account for over half of total dry matter losses. Even if the ground immediately below the hay is not receiving moisture, the surrounding soil is, which will leach into the soils directly underneath the hay stack. It is common to see molding occur on the lower bales due to direct contact with wet soils. The same sort of issues can occur even on concrete floors, as concrete is great at absorbing moisture, so make sure to keep this in mind even if your hay is being stored under a shelter.

Covering the tops of bales with something such as a large tarp or water-resistant canvas will help to divert moisture away from the stack. Make sure that there is some overhang of the tarp over the side of the stack, so that lower bales are not accumulating moisture. If bales are not going to be covered, it is advised to keep stacks small, as water from upper bales will penetrate directly into lower bales, increasing the number of damaged bales.

Ventilation is really important in continuing the drying process after bales become wet. For example, it is best to keep round bales in single layers placed end-to-end, with several feet in between rows to increase air flow and circulation around all bales. Bale density is also really important. The tighter the bale, the better it will be able to withstand winter precipitation and damage. Loosely-packed bales will “pick up” more moisture, and it will penetrate throughout more of a bale than a densely-packed bale.

Wrapping round bales will help to significantly decrease any quality and yield losses from winter storage if the equipment and resources are available. A study found that six layers of plastic wrap is ideal, as it is the optimal trade-off between money spent on wrapping and amount of hay lost to the elements.

Proper storage of your hay is really important in ensuring that your animals will have enough roughage to get through the cold winter months. Decreasing exposure to the elements is the most important factor, and minimizing the number of bales that are exposed to the winter elements will help to minimize total quality and yield losses.

November 12, 2014 1 Comment Montana Stockgrowers Association
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Concerns When Feeding Frosted Alfalfa


Emily Glunk Montana State Forage ExtensionBy Emily Glunk, MSU Extension Forage Specialist

I have been getting many calls and emails from agents and producers about how to graze their frosted alfalfa. The biggest concern with grazing frosted alfalfa is the potential for bloat. Bloat is a serious problem in livestock, especially cattle, and preventative measures must be used when animals are placed in bloat-inducing situations, such as grazing alfalfa.

While a very nutritious forage, with high energy and protein values, grazing of fresh alfalfa comes with its risks. Typically, if a pasture is less than 50% alfalfa, there is a reduced occurrence of bloat. Care must always be taken when grazing alfalfa, even “non-bloating alfalfa”. “Non-bloating” or “bloat-safe” alfalfa have lower amounts of soluble proteins, the cause of bloat in ruminants. However, animals should still be monitored, because even though it is considered “safe”, bloat can still occur.

Why does alfalfa cause bloat in the first place? Soluble proteins in forages and other small particles within the cells of the plant are rapidly released once they reach the rumen. These proteins and particles are attacked by slime producing rumen microbes, which cause a buildup of stable foam. The foam decreases the animal’s ability to expel rumen gases that are created from fermentation of plant material. These gases begin to accumulate, causing pressure on the diaphragm, leading to bloat. In severe cases, the rumen can become distended, and death may occur.

montana alfalfa bloom feeding ranching hay cattleSo when does alfalfa become “safe” to graze? This seems to be the money question, as you will find several different answers. We know that we can feed pure alfalfa hay to ruminants, without causing any issues. This is because that forage has gone through a drying process, and the soluble proteins are significantly decreased. But at what point does it become safe, and what are some strategies that we can implement to decrease the risk of bloat?

Some things to consider are the environmental effects. Freezing of alfalfa, and grazing frosted/ frozen alfalfa, can significantly increase the chance of bloat. After a frost, the intercellular liquids freeze, and can puncture the cell walls, causing the cell to “burst” and contents to leak out. Soluble proteins will be released, and the incidence of bloat will be increased. If cattle are out grazing alfalfa during a frost, remove them immediately.

Some studies say that only three days are necessary after a frost to allow soluble proteins to decrease, however others cite that waiting five to seven days is safer. As a precaution, I generally recommend waiting about a week after a hard killing frost before grazing the alfalfa, at this point the plant has significantly dried down and the risk of bloat will be reduced.

Other recommendations for grazing frosted alfalfa include:

  • If it was not a killing frost, then wait until the alfalfa is in full bloom rather than bud to early bloom to graze. Soluble proteins decrease with increasing maturity.
  • Make sure that cattle are not turned onto alfalfa hungry. Feeding with a non-bloating forage beforehand will decrease the likelihood of bloat as they will not consume the alfalfa as rapidly
  • Monitor cattle for bloat several times throughout the day, especially when they begin to graze
  • Consider including the bloat preventative poloxalene (Bloat Guard) into your ration

Livestock that are suffering from bloat will begin to swell rapidly on the left side. If it is a severe case, the animal can die within the hour, which is why it is important to be constantly monitoring your animals. Kicking at their sides or stomping their feet are other signs that the animal is experiencing discomfort. If you notice any of your animals exhibiting these signs, make sure to call your veterinarian immediately.