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The District launched a five-part workshop series about Comprehensive Nutrient Management planning (CNMP) in November, 2001. We hope you find the following summaries of the sessions helpful. Please feel free to contact our office for more information about CNMP or to receive a complete binder of the material presented in the series. |
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Comprehensive
Nutrient Management: Session One Date: Thursday, November 1, 2001 Welcome: Heather Ryan, MCCD District Manager Animal Feeding Operations (AFO) and Concentrated Animal Feeding Operations (CAFO): Mike Lynch, District Conservationist, Concord USDA NRCS office. The Clean Water Act was passed in the US in 1972. Since this time, Lynch feels the country has done a good job with point sources (PS) of pollution. Next on the agenda will be non-point source (NPS) pollution which is often viewed as being a primarily agricultural problem. At some point, farmers may be expected to have a written, documented Comprehensive Nutrient Management Plan (CNMP.) Lynch believes farmers already have a nutrient management plan or they would not be able to run a viable operation. Writing it down pulls all documentation into one place and forces the farmer to think through the various facets of nutrient management, including off-site manure disposal. Specific rules addressing AFO/CAFO issues are expected in 2003. Under currently proposed rules, EPA will consider an AFO operation a CAFO in need of a permit if it has the following characteristics: "more than 1000 animal units (AU)" or "301 to 1000 AU and discharge of waste directly or via any manmade ditch or structure into any US waters." There are an estimated 30,000 such operations in the US. EPA feels about 10% of them will require permits, at a cost of $830 to 925 million per year. About 1900 to 2400 facilities are expected to close when/if these regulations pass in their current form. AFO is a category that relies heavily on voluntary stewardship by farmers. Most New England animal farmers are AFO, defined as an operation in which animals are confined a total of 45 days or more within a twelve-month period and where vegetation is unable to be sustained over any portion of the feedlot. Proposed EPA regulations require a permit only if someone complains about an animal operation. NH Departments of Agriculture (NHDAMF) and Environmental Services (NHDES) currently receive and respond to complaints. At this point, no one knows if NH's state standards will be stricter than the federal government's; so far, this is the case in Maine, Massachusetts and Vermont. You can find a list of documentation you'll need to write your own plan at the end of this session summary. Lynch recommends using a land grant college for soil tests, to ensure consistency. He also suggests farmers look for Conservation Planning Policy certification from NRCS when hiring a consultant to write a plan, should you decide to go that route. He believes a well written plan includes consideration of animal health and quality of life issues for humans and animals in addition to the financial bottom line. NH Perspective on NMP's and Grant Funds Available: Dick Uncles, NH Department of Agriculture, Markets & Food (NHDAMF.) Uncles stated that most states are ahead of the federal government in the area of NMP. Maine already has livestock licensing and CNMP for any operation of over 100 AU. NH has little in the way of regulations so far, perhaps because money needs to be spent to ensure compliance. There is no one in the state to spearhead such an initiative, at least in part because we do not have as much livestock other New England states. Federal regulations tend to be "one size fits all," so NH, with relatively little ag pollution will get the same regulations as NC, where agriculture is one of that state's top pollution sources. The NHDAMF and NHDES work together to regulate agricultural pollution. DES has authority under the federal Clean Water Act to regulate farms. At present we have a "complaint only" system. Both departments understand agriculture is a fragile industry in New Hampshire. Uncles has noticed a real change in public attitudes in the past couple of years; the general public now sees manure as a potential poison rather than a fertilizer. He has received an increase in complaints about cattle in streams and wetlands. Solving this problem can require fencing off a mile or two of wetland or stream for a summer pasture, a fiscal impossibility for many small operations. EQIP funds are mainly geared towards larger operations and 319 grants for NPS pollution are highly competitive and increasingly spread very thinly. Small farmers Uncles meets are willing to act, but there has no money to help them. Growth in the home gardening market and a corresponding segmentation of the fertilizer market have resulted in an increase in NH's fertilizer registration funds. Uncles asked NH Ag Commissioner Steve Taylor to set aside $20,000 ((20%) of these funds. The money will be matched with $30,000 from DES, creating a new grant program to help small animal operations improve environmental water quality. Application deadlines for the new grants are December and June. Proposals should stress the connection of the project to water quality improvement and should cover simple on-site projects. In-kind contributions such as labor will strengthen a proposal. Potential projects include: concrete paths, roofing, downspouts for barns, creation of vegetative swales and waste divergence schemes; compost pads and new wells for the farm will not be covered. There is a cap of $2,500 per farm. Call Uncles at (603) 271-3685 for further information. Comprehensive Nutrient Management Plans: Stefan Seiter, University of NH. Seiter spoke about the benefits, goals and planning of CNM and about nitrogen and phosphorus management. Nonpoint (NPS) pollution is the nation's largest water quality problem. Agriculture has been identified as the number one source of NPS pollution. Seiter believes a well formulated CNMP will:
A well written CNMP will use Best Management Practices (BMP's) to minimize leaks in nutrient cycles as material moves through a farm. This requires an understanding of nutrient behaviour in soils, manure and fertilizer. The same nutrient appears in different forms within various nutrient cycles. Each cycle carries with it the potential for loss of nutrients via leaks. The process of formulating a CNMP involves the following steps:
One of the things Seiter emphasized is the importance of soil testing and the importance of taking proper samples of soil; results are only as good as the samples taken. He recommends taking many subsamples from each field and sticking with one lab with which you are familiar. Some of the best nutrient management tools are almost free:
Phosphorus (P) exists in three pools in the soil, moving from one physical/chemical state to another according to conditions. When the soil becomes saturated with P, there is a high potential for dissolved P leaching or running off into surface waters, causing eutrophication. P is much less volatile than nitrogen (N) and crop uptake of P is relatively small; most NH soils are too high in phosphorus. Seiter suggested farmers experiment to see if a non-phosphorus starter fertilizer might not work well on high P fields. UNH Extension Service can help set up such a trial. A clear understanding of the nitrogen and phosphorus cycles is extremely valuable. For example, it's possible to skip manure application some years because from 10% to 20% of N in the manure you apply this year will be available next year, about 5% the second year and 2% the third year following application. Seiter noted the following characteristics of smart N and P management:
Resources: A Comprehensive Nutrient Management Program Technical Guide is available from MCCD. Call Lisa Morin at (603) 223-6023 to receive a copy. |
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Comprehensive
Nutrient Management, Session II: Date:
Thursday, November 15 Lynch recommends doing an inventory of your farm, including an environmental assessment. MCCD has soil maps and aerial photos of the entire county which will help identify water sources, fields and wetlands on the property. It is a vital "good neighbour" policy to consider the wells, streams and other water sources of abutters. You can use this information to estimate how much land you have available for spreading manure and which fields are accessible in the early spring. Soil maps indicate slope and soil type-including water table level-and permeability of the various soils on your land. You should avoid creating high P levels in the areas with the most erodable soil. NMP components: Yield goals should be realistic to avoid overfertilizing. Some soils will not produce as much as you might like and won't require as much fertilization. A CNMP needs to address manure storage, including type, number of sites and safety issues. Field stacks should be appropriate in amount to the needs of the field upon which a particular stack is sited. Nutrients enter the farm as grain and fertilizer and exit as milk, corn, hay, manure, erosion and other products and byproducts of your operation. It's important to consider if you have too many nutrients coming on to the farm for your needs. Soil testing and good record keeping play a major part in answering this vital question. Given the litigious nature of our society, record keeping of nutrient application and site assessments are especially vital if you rent fields. Soils-Nitrogen and Phosphorus: Tom Buob, UNH Cooperative Extension. According to Buob, the three goals of nutrient management are to: match resources with needs in an environmentally sound manner, minimize the risk of nutrients movement off site and minimize negative impact on farm profitability. The three big issues of nutrient management in New Hampshire are the soils, nitrogen and phosphorus. When assessing soils, one needs to consider various physical and chemical properties. Typically there are about a half dozen soils on a farm property. This wide variety presents a challenge to NH farmers. Crops need to be matched to the soil in each field. Physical properties include the drainage class, water holding capacity, slope, rooting depth, permeability and texture. These determine what you can grow in a particular soil. The national soil survey results, available through MCCD, define 274 soil series in NH. The soil maps indicate location of these series. Chemical properties of soil include pH, nutrient status, saturation levels, sorption capacities and desorption patterns. A crucial soil test in assessing P is sorption/desorption. Different soils take up and hold (sorb) and release (desorb) differing amounts of P; desorption may be the more important of the two for the environment. You only need to do this test once per field. Sources of nitrogen include manures or other organic residuals, including sludge; soils; fertilizers; previous crops, including cover crops and nitrogen fixation. Again, some soils trap more N than others. Legumes greatly reduce the need for added N in later crops. Nitrogen comes in organic forms such as proteins, amino acids and globs of stuff (such as bedding) containing N (such as manure.) Inorganic sources of N include ammonium, nitrite and nitrates. 90% of our drinking water is groundwater. We grow corn over our drinking water so it behooves us to minimize our use of N. Straight manure is dense and doesn't compost easily so it's good to have bedding to break it up. Urea decomposes into ammonium, which in turn breaks down in to nitrite, then into nitrate. Of these only nitrate is available for use by plants. Completion of this nitrogen cycle is required for manure to become plant available. A nitrate test estimates how much N will be available in the future. Nitrate fertilizer dissipates more quickly than the naturally occurring nitrates. If you have your soil tested soon after adding nitrate fertilizer it will skew the estimate of available N. Nitrogen is fairly volatile and should be worked into the soil quickly to prevent loss into the air, a normal part of the nitrogen cycle. Sandy soils are vulnerable to leaching and denitrification happens readily in waterlogged soils. Cover crops like winter rye prevent leaching of fall-applied manure by binding the N into the plants. The N is released as timely plant-available nitrates when the plowed-under cover rots in the spring. Spring is the ideal time to apply urine because it mineralizes rapidly in a plant-available form. Solid feces release the N more slowly and some is retained in the soil for several years. You need to account for this residual carry over in doing your nutrient assessment. Liquid manure varies widely in the amount of N. If you manage your manure spreading using plant available N and accounting for the residual N from previous applications it will decrease your P application because you'll use less manure. A soil nitrate test will tell you if you're going to need more N in the future. This will enable you to apply the proper amount early in the spring while you can still get into the field without hurting the corn. Issues in N management include: setting reasonable goals (e.g., 24-28 T/acre instead of 30T); including N credits from prior applications; applying reasonable rates of manure at the optimal time; incorporation of N into soil soon after spreading; use of soil nitrate test (PSNT); use of cover crops; keeping and analyzing good records. If you understand the growth characteristics of your crop you can time your fertilizer applications appropriately. Combining grasses maximizes yields over time and across soils and climate conditions. Buob feels a grass/clover mix gives the best yield. Buob cautioned participants to question whether they actually need the P in starter fertilizer. Soil testing will reveal which fields are already high in P, a growing problem in NH. Good use of soil testing can save a lot of money by cutting down on excessive fertilizer use. The soil nitrate test can be a pain but it really fine tunes fertilizer use in corn and saves money. Keeping good records is important, but only if you analyze them to determine the needs of your soils. Sources of P are manure, previous crops, cover crops, fertilizers and existing soils. Even when P levels are high in the soil, so many factors affect bioavailability that it's hard to get it into the plants. The minerals in grains are the biggest source of P on a farm; 70% of it goes right through the cow in a highly available form. Composting concentrates P and increases bioavailability. Until recently scientists believed phosphorus was only lost via erosion, but runoff and leaching cause more loss that was previously recognized. P is being recognized more and more as a danger to the environment, but we do not completely understand its effects on the ecological system. Voluntary stewardship of P is essential to prevent legislative enforcement; Delaware went from no nutrient management to very strict regulation in only one year. Many soils in NH have high P levels. If soil is very high in P it will not respond to added P and you are wasting your money, possibly endangering the environment and increasing the risk of legislative involvement. Buob recommends using potash starter with manure later on high-P fields. He also believes careful crop rotation will help manage your N/P needs. While it is true that manure application in the rain helps N enter the soil quickly, it actually increases P runoff. This is especially serious if the field is near a body of water; manure application in this case is contraindicated prior to heavy rain or in fall. There are some compelling reasons to manage for P: 50 % of the P coming in stays on the farm and levels build up in soils; the EPA considers agriculture the largest contributor to nonpoint source pollution in the US (good proactive recordkeeping can help prove/disprove this belief); the NRCS nutrient management standard (590) and TMDLs. Buob believes we don't have enough data yet to fully manage P, but we can begin to do a better job according to what we're learning. If you have good records you can make good management decisions and save money. Different soils require different management. You need to match your crop to the soil, using the information you've gathered in your assessment. Soil Quality: Don Keirstead, NRCS Soil Conservationist, Concord Office Keirstead was unable to present his information due to unforeseen technical problems. He will do his presentation during the field tour session. |
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Comprehensive Nutrient Management: Field Tour Morrill Dairy Farm, Penacook, NH Date: Saturday, November 17 Refresments and Introductions: Heather Ryan, MCCD District Manager Farm Overview: Mike Lynch, District Conservationist, NRCS Concord Office and Rob Morrill, Morrill Dairy Farm It's easy to put things on paper in an office, said Lynch, but it's important to walk through a real farm to see how things work in the real world. As we stood in the barnyard, we could see two groups of cows. As Lynch pointed out, the two groups each have different quality of manure because of the difference in the cow's milking status and feeding regimen. Mixing the two manures brings up certain problems in assessment of the nutrients in the total mass. The textbook solution is to incorporate the manure with the liquid and analyze the result. In reality, because the total mass is too solid it's not feasible to agitate it sufficiently to create a homogenized mass. Other factors such as time of year and whether the manure is covered or uncovered, affect manure nutrient values. Lynch recommends using weighted individual "book values" for young stock, dry cows and milkers, averaging the numbers to estimate total manure nutrient values. This is probably no less accurate than sampling an insufficiently mixed load. Estimation takes some work but is do-able enough to defend. Lynch pointed out Morrill Farm's many barns of varying sizes and shapes and water coming off at many angles and heights make it hard to keep clean water from dirty. One strategy is to keep roofed areas as clean as possible, so they scrape a lot more than is usual. In the long run, this saves wear and tear on equipment and the lagoon used to store liquids. The sloped barnyard is covered with impervious "dirty dirt," also known as "poor man's concrete." The intentional slope allows the area to drain into the lagoon quickly and dry out faster which in turn means the Morrills can scrape the area sooner. This creates more collected liquid but if you have a large enough lagoon that's not a problem. You can irrigate from the lagoon, but you should account for the nutrients contained in the water. Maintenance of such a system is vital. The lagoon should be dredged occasionally, so it's good to limit the solids that go into it. You can spread the solids from the dredging. These recommendations apply to silage also. "One of the most noxious leachates on a farm, says Lynch, is the stuff coming out of a bunk silo." You pay for all the nutrients coming into your farm in the form of grain, silage, fertilizer and such. The fewer nutrients you lose in runoff, the less money flows out of your pocket. Nutrient Planning for Biosolids: Charley Hanson, White Mountain Resource Management Hanson pointed out that because sludge/biosolids is such a heavily regulated industry "We've always had to have nutrient management." Purveyors of biosolids or sludge are required to sample all fields yearly due to P concerns. They have to balance the C/N ratio in their composting. Too much lime leads to excessive calcium. Hanson's company carries products other than biosolids, including short fibre paper pulp. This pulp is organic matter and is good for holding nutrients. Paper fiber his company has added to one sandy area hit by the 1938 hurricane has increased water/nutrient retention by two percent. In order to get a permit to spread sludge or biosolids you will needs a map of the farm indicating all water sources, residences and runoff areas; a description of the intended crop and an analyzsis of the proposed biosolid, including its origin and nutrient levels. You will need to account for residual nutrients from past soil amendments on each field in question and consider the timing of application in your proposal. Hanson feels biosolid management plans are a good model for nutrient management. At present the DES regulates farms using biosolids/sludge, but not manure. You must have a 250-foot setback on designated rivers, 75 feet on undesignated. Manure and lime are exempt from this restriction unless you top dress, in which case the setback is 150 feet. Hanson feels it's important for farmers to be involved legislatively and is disturbed there are no farmers on the state Agriculture and Environment Commission. Lynch added that any designated stacking sites should be noted in your CNMP. You should indicate any berms or other features that reduce runoff and allow you to reduce setbacks. Cover crops and areas of reduced tillage should also be noted. Soil Quality Testing: Don Keirstead, NRCS Soil Conservationist, Concord Office Keirstead demonstrated use of the comprehensive soil testing kit MCCD purchased with funds for this workshop series. Contact Lisa Morin at the office to borrow it. Infiltration rate is an important factor in assessing runoff and retention in a field. It is heavily influenced by compaction. Keirstead demonstrated a simple test using a slender metal rod to measure the depth of the "plow pan." The higher the plow pan, the shallower the available rooting area. Alluvial soils are particularly prone to compaction. Some things can be done to mitigate compaction: sub soiling; deep tillage; mixing alfalfa, a deep rooter which breaks up compaction, with other crops. Growing corn will degrade soil in a field over time because of the combination of shallow roots and the need for frequent tillage which destroys soil structure and beneficial organisms such as microbes, earthworms and insects. Going into your fields too early in the spring will increase compaction. Keirstead warned of the dangers of the frost pan for New England farmers. To measure aggregate stability of the soil, an important factor in assessing potential for soil erosion, you put small peds of soil into tiny baskets supplied in the kit. Immerse the baskets in water and observe the stability of the peds when you agitate them a bit. The more the peds remain intact, the greater the stability of the soil. Plowing is a degrading factor due to its ability to break up the fungi hyphae and other organisms that literally hold your soil together. When you do your field assessments, note areas that puddle up easily and stay wet longer. The cure is increased organic matter to improve soil structure. Also note any surface crusting which is caused by fine particles collecting on the soil. Keirstead demonstrated use of a soil ring to measure infiltration rate. The small metal ring is covered with plastic wrap and 450 ml of water is poured into the ring. Remove the plastic wrap so the water is released all at once and time how long it takes to sink into the soil. Keirstead also pointed out that tilling adds oxygen to the soil. Nitrogen combines readily with the added O2 and volitizes into the atmosphere. If you do not till your corn stubble in the fall this interaction will not occur and your N will remain in the soil for use by spring seedlings. Cover crops, of course, take this one step further by actively binding up the N in the field for release later. Keirstead shared a small, plastic-coated booklet called a Soil Health Log and encouraged participants to use it in their fields. It contains a wealth of information about soil health indicators and corn and alfalfa scouting calendars. An adapted copy is available at nominal cost from the District office. |
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Comprehensive Nutrient Management: Session Three Development of Nutrient Management Plans Date: Thursday, November 29 Welcome: Heather Ryan, MCCD District Manager Nutrient Management Design and Specifications: Tom Buob, UNH Cooperative Extension There is a cost to poor nutrient management. Good nutrient management not only minimizes environmental impact, it maximizes economic benefit. You can think of nutrient flow into and out of the farm in terms of inputs/outputs, in which purchased feed, fertilizer and legume N enters the farm and is converted to salable animal products and crops. Or you can use the model of cash pathways in which there is income from sales of meat and milk and outgo in terms of purchased fertilizer and feed. Either way, some of the purchased items are lost in the conversion process to runoff, leaching and other forms of costly waste. This waste comes out of your pocket, lowering your net profits. Buob also thinks being able to explain to others what we're doing is becoming increasingly important. One point Buob brought up is the need to label your fields consistently, especially if you do a lot of soil sampling. To maintain consistency, all agencies or agricultural businesses with whom you do business should use the same field names you do. Buob offered some animal intensity levels formulated at Pennsylvania State University in the mid-90's. Low intensity is defined as fewer than 1.25 animal units (AU)/MA and less than 60% feed imports. The issue in this situation is to maximize efficiency of manure use. Medium density is defined as 1.25 to 2.25 AU/MA and 60-90% feed imports. The issue here is to maximize safe utilization. In a situation of high density (>2.25 AU/MA and >90% feed imports) the issue is to use all available means to remove excess manure. You should get an analysis of N and P in your feed from your dealer. There are formulas available to convert protein levels into N. MCCD or UNHCE can help you find them if your feed dealer doesn't have them. Writing a Comprehensive Nutrient Management Plan (CNMP) is an ongoing process because it is a working document that changes over time. It takes time to set up and requires ongoing revision due to new or changing information. There are seven basic steps in writing a CNMP:
Buob recommends encasing the pages of your records in plastic sleeves so you can use them without abusing them. If you computerize your records, be sure to back them up. It doesn't hurt to keep a copy off premises. Individual field information includes:
The more you learn about your soils, the more you will understand some of the limitations you face. For example, fertilizer can't change physical characteristics that may impede growth. Your field information file should include, for each field:
Resource information should include sources of nutrients: NPK for soil, manure, residuals in soil and any other nutrient credits you can think of. When assessing nutrients consider soil fertility levels; manure analysis and availability; residuals analysis and availability and cover cropping and rotational effects. Soil test information includes: level of nutrients; organic matter levels; recommendations for additional nutrients and environmental ratings. P greater than 25% has an increased risk of movement off site. Crop information for each crop type and variety includes: planting population; year in rotation; crop yield and crop quality. Your management records should include: amounts of nutrients applied; time of nutrient application and timing and amounts of harvest. Some things to consider when analyzing your records are:
There are three hotly debated options in phosphorus management:
The P index is a site evaluation tool that attempts to rank fields by risk of offsite movement. It considers many factors of both source and transport. Source factor include P is coming from; how much is being applied and how and when it is being applied. Transport factors to look at include erosion potential; runoff potential; flooding frequency and buffer width. Buob recommends winter rye as a cover crop. In New Hampshire it provides good root growth during periods of maximum nutrient loss. He recommends the Penn State College of Agriculture Nutrient Management Plan Writing worksheet, available for download at the college's web site. Biosolids Regulations: Mike Rainey, NH Department of Environmental Services The first point Rainey made is that DES is interested in the environment, not your profitability. It defines an agronomic rate of sludge/biosolid application as being that which provides the amount of N needed by a crop which minimizes the amount of N that passes below the root zone to the ground water. DES sets maximum annual application rates (AAR) per acre for septage based on N needs of the particular crop. There is a permitting process required in order to use septage which includes a public hearing. AAR determination requires annual soil sampling and testing by UNH Analytical Services Lab. AAR is calculated using N recommendation from UNHCE which accounts for soil fertility, crop type and yield potential, according to 40 CFR Part 503 and state regulations. For example 50 lbs./acre (UNH N recommendation) divided by 0.0026 = 19,231 gallons/A/year AAR. Some post-permit compliance issues concern amount and type of application. You cannot exceed per-acre or total site AARs; you must spread septage evenly and document actual AARs per acre and for the total site. Environmental concerns such as buffers and timing of application must be met. The soil must be tested for presence of metals and there must be documentation and certification of both pathogen and vector attraction reduction (VAR), under penalty of perjury. Finally, DES requires an annual report. A prospective sludge user must file a NMP which includes:
Some elements of a BMP worksheet are:
Rainey sees some changes coming over the horizon, including stockpiling and reclamation requirements and pathogen reduction changes. Potential septage rules changes include hauler certification, storage and holding tank rules and innovative/alternative (I/A) facility permits. There is consideration of using P instead of N as the limiting nutrient. NHDES wants to use the agronomic P option. Farmers who prefer site index need to let the department know this. Developing Your Plan Using NRCS Worksheets: Mike Lynch, District Conservationist, NRCS Concord Office Lynch pointed out that, though he recommended use of book values of manure nutrients during the field tour when assessing manures from mixed sources, in this session he covers about the ideal--testing of manures for nutrients. The more productive a dairy herd is, the higher the volume of manure it will produce. Lynch distributed Solid Manure Volume Estimator work sheets and discussed their use. Contact District Manager Lisa Morin for a copy. Soil and Water Best Management Practices: Mike Lynch, District Conservationist, NRCS Concord Office Lynch went over several handouts, including the Environmental Concerns Checklist. Copies of the handouts are available from Lisa Morin, District Manager. Lynch discussed hydrologic soil groups, which are designated by letter (A,B,C,D) on soil maps. Leaching is influenced by intensity of rain and by soil type. A soil with a score of 2 to 10 has medium leaching potential. The Universal Soil Loss Equation is an erosion rate calculator that indicates soil movement, not necessarily soil loss off site. Lynch said a woody buffer is better than a grass buffer. A sod waterway is better than a gully. He agrees with Buob on the merits of winter rye. Winter rye ties up N; controls erosion; facilitates organic build up, which leads to increased productivity over time; and it grows before corn is harvested, which allows it to tie up nutrients quickly. |
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Comprehensive Nutrient Management: Session Four Alternative Options for Nutrient Management Date: Thursday, November 29 Welcome: Heather Ryan, MCCD District Manager Animal Feeding Management--Feeding to Reduce Manure Nutrients: Peter Erickson, UNH Assistant Professor of Dairy Management Nutrients enter the farm in the form of purchased feed, fertilizer and bedding; new animals and via N fixation, rainfall and irrigation. The greatest expense is feed. The higher quality feed you can grow yourself, the less money you'll spend of purchased feed. You can control the amount of fertilizer you purchase through judicious use of soil testing. Other factors are much harder to control. Nutrients leave the farm in the forms of cows sold, milk, manure and compost sold and via volitalization, runoff and leaching. For many years farmers have been advised to feed P to cows at a rate higher than the required .48% of DM in order to improve reproductive performance. Data determined in the 1950's have been used to determine availability to cows of P in sources. Recent research conducted by Wu and Satter at the US Dairy Forage Research Center in Wisconsin does not support this advice. They found no statistical difference in performance among cows on diets with varying amounts of P, i.e. no benefit to adding P above a certain level. Apparently the more P you feed a cow, the less they absorb per unit of feed. The level of P in manure, on the other hand, is directly related to the amount of P in the feed. The current recommendation of .4% should maximize available P to the cows and minimize amount of P in manure. Less P in feed means savings to the farmer. The P in corn is unavailable to non-ruminants because they lack an enzyme necessary to break down plant P. You need to add this enzyme to make it available to swine and poultry. Increasing the digestibility of feed reduces the amount of supplemental P imported to the farm. Phosphorus (P) is becoming of increasing concern as a pollutant. It is a serious problem wherever a large livestock population exists because it take 18 years to leave the soil. Phosphates move to surface waters by overland flow and erosion; P concentration in surface water is often considered the leading indicator of water quality. An overconcentration of P leads to eutrophication with resultant O2 depletion and fish kill. Erickson told participants "If you get one thing from this talk on phosphorus, tell your nutritionist to lower P in dairy cows' diet to .4%. This will save costs. Any way we can increase efficiency of production of milk per pound of feed to increase the (off-farm) export of products will improve the environment and increase your bottom line." Efficiency should start with high quality forages which will result in reduced needs of purchased supplements. There are several ways to increase the efficiency of your operation:
These three practices are additive; you can do all three and reap benefits from each of them. Anything you can do to reduce stress will increase milk production--hoof trimming, good ventilation, anything you can do to improve cow comfort and health will increase production. Good operators who manage their farm well will see increased production. Erickson quoted a successful farmer he knows who said of his farm "This is a home for mothers." He described a farm where the farmer had to remove the roof of his closed barn one winter. Much to his surprise, milk production increased as a result of the improved ventilation. Erickson recommends high quality diet for dry and pre-fresh cows, which makes for better birthing results. Almost every farm in New Hampshire has an equal number of heifers to milking cows, but if heifers calve by 24 months you should only need a ratio of 2/3 unless you're expanding your herd. There are several useful feed additives:
Erickson went on to share information presented by Chuck Schwab of UNH at the Poulin Grain Dairy Producer Meeting in Burlington, VT in November, 2001. Schwab's presentation focussed on dietary requirements for milk production and the formulation of diets for high milk-protein production. Until a few years ago protein in milk was not an issue for farmers because they weren't paid for it. The process of creating milk proteins in a cow is quite complex. In this process, milk production is directly proportional to the amount of lactose (milk sugar.) Microbial protein is highly regarded. It is produced by bacteria in the rumen and is "what makes a cow a cow." Many factors can affect milk yield: fresh water; high quality feed; a balanced, consistent diet with effective fibre and fibrous byproduct feeds; frequency of feeding; good feed bunk management; cow comfort; milking frequency; BST and amount of light per day. Optimizing carbohydrate nutrition is the first step in increasing milk protein production. To maximize milk protein concentrations, feed a mixture of high quality forages, fibrous byproduct feeds and complementary energy feeds to optimize rumen function and yield of microbial protein. The challenge is to increase intake of fermentable carbohydrates without compromising rumenal digestibility of OM, rumenal fermentation, feed intake and animal health. Optimizing protein nutrition is the second step to increasing milk protein production. Feed adequate, but not excessive, amounts of rumen degradable protein (RDP.) RDP is determined by the amount and type of fermentable carbohydrates in the cows' diet. It is important to synchronize carbohydrate and protein release in the rumen by feeding fermentable carbohydrates such as alfalfa haylage with degradable protein such as soybeans. You should rely on feed intake and milk urea nitrogen (MUN) to make decisions. MUN is an indirect measure of protein utilization. Herd levels of 10 to 12 mg/dl are adequate. A high level indicates high amount of protein waste. This will end up as nitrogen in the manure. Feeding for more milk protein seldom requires feeding more protein. Your focus should be on increasing efficiency of use of feed protein. One approach is to optimize intake of essential amino acids (EAAs). Amino acids are the "building blocks" of protein. There are a total of 22 amino acids, of which eight or ten are not produced by the body; these are the EAAs. Lysine and methionine are the most limiting amino acids. Increase those two and you increase the amount of protein in milk and decrease the amount of N in the manure. Researchers found that dairy cattle responded to lysine and methionine supplementation with variable increase in BW gains and feed efficiency and variable decreases in urinary N excretion. They also found variable increases in content and yield of milk protein, variable and generally small increases in milk yield and occasional increases in milk fat content. You can mix and match protein supplements and incomplete proteins (those lacking certain EAAs) to improve the profile of EAA in RUP and, thus, in metabolizable protein. For example, soybeans are high in methionine, low in lysine. Corn is high in lysine, low in methionine. This is why a soy-corn mix is the basis of pig feed. Schwab's research indicates fish meal is the best choice for dairy cows. He has formulated a suggested diet, included in the presentation slide handout or available from him at UNH in Durham. Alternative Manure Uses: Mike Lynch, District Conservationist, NRCS Concord Office Lynch spoke about alternative ways of treating manure nutrients and transporting them off the farm. For example, when you put cows and heifers on pasture--not good hayland--they pick up nutrients from grazing and deposit manure which fertilizes that pasture. You can also engineer a wetland to treat liquids on site. If you can separate the liquid from the solids it's much easier to handle. Lynch showed a picture of a four-celled system. Bedding can be dried out via mechanical screening and reused as bedding or composted. The liquid can go into an onsite lagoon or engineered wetland. Anaerobic digestion of manure produces methane which can be used for heating or to generate electricity. We do not have an electric co-op to buy the electricity so that's not as feasible here in NH. This system also doesn't reduce nutrient levels. For that reason, Lynch feels Erickson's feed management and Seavey's composting suggestions are probably more useful. Composting: David Seavey, UNH Cooperative Extension, Merrimack County There are some distinct advantages to composting manure:
Cow manure is dense, however, and if you just let it sit you get anaerobic digestion, which leads to objectionable odors. N can also become concentrated and run off into the surrounding area. Horse and sheep manure are good composting materials because of the large amount of bedding in them. Swine manure is very dense. The essentials of composting are fairly simple and consist of:
The ideal composting conditions are 30:1 C/N ratio; 5% O2; 90-140 F temperature and 40-60% moisture. A good test for moisture is to squeeze the material. It should be moist but not dripping. When the temperature of the pile reaches 140F, turn the material to cool and aerate it. If the temperature is too high it kills the bacteria; too low and the process stops. Eventually the temperature goes below 120 degrees F even when you turn it, when it's about 87 degrees set it aside to cure. Wood chips are an excellent bulking agent to provide C; ask your road agent for tree trimmings. You can also use cardboard, corn stalks, pine cones, shredded paper (not glossy), weeds (prior to seedhead formation), mulch straw/hay and brown leaves (you may have to water leaves). Bulk will reduce by half during the process. Grass clippings compost, but are a source of N, not C. Seavey recommends the On-Farm Composting Handbook and the Field Guide to On-Farm Composting. He also has detailed information on the economics of composting. Some problems (and their cures) that can occur with composting are:
Health and safety issues include dust, molds, fungi and the presence of pesticides or other chemicals. When siting a composting operation:
There are several composting methods. Passive composting requires little turning and is appropriate for something like a leaf pile. You can create windrows, even double windrows which are incorporated into one another as the material shrinks. Make sure the row runs up and down any slope to prevent puddling between rows. You can aerate a static pile by building it on a grid of PVC pipe with holes drilled every four inches. Or you can compost in a large vessel. You can sell finished compost to landscapers, nurseries, greenhouse operators, golf courses, parks, market farmers and home gardeners. A good soil mix for resale is one part compost, one part peat moss and two parts perlite. Compost has to be very mature for seedlings. It should be tested for soluble salts. Seavey has a conductivity meter in his office or UNH will test your compost. Creative Manure Storage: John Porter, UNHCE Porter said some governmental agency people are now thinking of farm manure as requiring the same treatment as human manure; they want it totally contained. Until their point of view prevails, there are several options for manure storage, besides free stalls which Porter feels present more of a challenge with bedding sand and odor. The first is in-field storage, something purists dislike. You can compost the manure in the field this way. Make sure your pile is properly sited, surrounded by berms to reduce liquid runoff. You can catch solids with lattice and allow liquids to run into a lagoon via a grassway. When building a barn, you can include an angled ramp the width of a bobcat. Gravity will take care of most material but you'll need to scrape out the bedding sand that accumulates. Porter described one farmer who uses the last quarter of his covered free-stall barn for manure storage. Lining your pit with vinyl limits access of machinery for scraping. You can go 100% liquid and use it for irrigation. There is the greenhouse barn, built over the manure pit and solar heated. The solar heat evaporates the liquid. There are various methane systems that collect manure, pass it through a plastic tunnel to collect the gas. This is not a good economic choice in NH, plus the sulfur in the gas corrodes engines. A fan separator relies on a giant corkscrew; the liquids go in one direction, the solids in the other as the manure passes through. Porter agrees with Seavey that composting and selling the results is a good option. The latest trend is a channeled type methane gas generator. They capture solids with a separator and pass only the liquid through the methane-capturing maze. The gas is used to produce heat in a boiler to dry bedding for reuse or composting of manure solids. |
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