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Permalink How can I promote native forages in my pasture and control Texas croton?

R.E.
Texas

Answer: Texas croton (Croton texensis) is sometimes called "goatweed." Croton is a native warm-season annual forb that becomes very coarse, almost woody, when mature. It frequents disturbed sites on sandy to sandy-loam soils, whose seeds are valuable for birds. Seed spread by birds may account for infestations of this forb into range sites in good condition.

Native pastures are resilient, consisting of numerous deep- and shallow-rooted plant species that occupy all the available niches above and below the soil surface. Maintaining a dense, productive pasture includes fostering plant diversity and managing defoliation through mowing or grazing to benefit native plants while discouraging weeds.

Mowing

The frequency of mowing for the control of annual weeds like croton depends on rainfall. A single summer mowing is usually beneficial after flowering but before the seeds set. However, additional clippings will be required if later summer rain results in significant lush weed regrowth. Mowing after flowering in this manner will reduce weed seed production and decrease the amount of weed seeds in the soil for the following year.

Native grasses do better when mowed while dormant. However this is difficult to achieve when controlling croton on Texas rangeland, because the croton is blooming when the grass is still vegetative. In addition, some grass species might be bolting (stem elongation for seedhead production) at this time. If the grass is still green, mow as high as you can to remove weed tops after flowering but to try to keep the growth point of the grass intact. Prior to bolting the grass growing point is low, whereas after bolting the grass growing point is elevated with the developing seedhead. Tall bunch grasses can regrow from above-ground growing points when they are mowed or grazed prior to seed stem elongation. Cutting native grasses like little bluestem or switchgrass when a seed stem is present forces the plant to regrow from root reserves, which is a slower process than if cut prior to stem elongation. During this time, annual weeds have an opening to exploit and can get ahead of native grasses. This is why management to maintain grass in its vegetative stage (prior to seed stem elongation) is critical. Grass is much more competitive when it is actively growing.

In a stand of perennial native grasses, not every plant will produce seed each year. In addition, seeds of many kinds, including perennial grasses, lie dormant in the soil. Mowing for one or two seasons will most likely not have a long term negative effect on native plant longevity. More destructive forces like non-native invaders, overgrazing, and erosion are a bigger concern for native plant loss.

Grazing

Control of seed production is only one strategy in annual weed management. Another management technique to employ is prescribed grazing. Prescribed grazing can be thought of as a process of developing a grazing system that seeks to integrate the economic and ecological realities that ranchers are faced with on native range. The controlled harvest of vegetation with grazing or browsing animals, managed with the intent to achieve a specified objective, is referred to as prescribed grazing. Management objectives addressed by prescribed grazing include:

• Improve or maintain the health and vigor of selected plant(s) and to maintain a stable and desired plant community;
• Provide or maintain food, cover, and shelter for animals of concern;
• Improve or maintain animal health and productivity;
• Maintain or improve water quality and quantity;
• Reduce accelerated soil erosion and maintain or improve soil condition for susceptibility of the resource.

A very crucial aspect of a prescribed grazing regime is the development of a workable and ecologically appropriate grazing management plan. Designing an effective grazing plan isn't as daunting as it seems. Mostly it is applying observation to management, observing some more, and then adjusting as needed. There are five areas to consider in developing a grazing plan. They are (1) Inventory, (2) Define Goals, (3) Determine Grazing Units, (4) Develop a Schedule, and (5) Development of a Monitoring and Evaluation Plan.

Inventory

This is for gathering baseline information to allow you to make appropriate decisions about land and pasture use. Find out what plants are in each pasture, and evaluate the pastures based upon a condition score. Utilize features such as key species, percent canopy cover, amount of bare ground, presence of noxious weeds, annual forage production in pounds per acre, amount of residue, etc.

Define Goals

Make a list of what you want to accomplish. This will be a list of your expectations and will guide you in making plans and decisions. Do you want to improve the economic value of the ranch? Maintain wildlife habitat? Improve water quality and quantity? Reduce noxious weeds? Also consider available acreage and the amount of time you have to put into this project.

Determine Grazing Units

Divide the pastures into units that you can rotate animals through. This will allow you to rest pastures and allow for regrowth following grazing. It will also allow you to rotate grazing on a seasonal basis as well. Determine how much forage is available in each grazing unit and map it out. Note key species, percent cover, water availability, facilities, and other aspects important to you. Remember that livestock should always be within at least two hours walking distance from water. This will help you to determine grazing unit size (for large parcels).

Develop a Schedule

This will be a graphic illustration of your plans for grazing each unit during the grazing season. Develop the schedule based on your total Animal Units (AUs) and available Animal Unit Months (AUMs) in each unit. If you have a 100 acre pasture with 2 AUMs per acre, you have 200 animal unit months of forage available. At 50 percent allowable use, cut it in half to 100 AUMs. This means you have enough forage available to feed 100 animal units for one month. Or, said another way, 50 animal units for two months, 33 for three months, and so on. For more detailed information on calculating AUM’s see the Montana Grazingland Animal Unit Month (AUM) Estimator located at: www.mt.nrcs.usda.gov/technical/ecs/range/technotes/rangetechnoteMT32.html

Important concepts here are duration of grazing and time for regrowth. Some range ecologists and managers believe that grazing intensity is also important, and it is. A plant needs to have green leaves left after grazing for photosynthesis and subsequent regrowth. However, others feel that grazing severity isn’t as important as regrowth time. Whichever you choose, it is important to remember to allow plenty of time for adequate regrowth before the animal gets to bite a plant a second time. Take a look at the native plants on an upland range site if you have the opportunity. Some, like little bluestem, are large-statured and can handle several bites from an animal in one grazing event. Some, like black grama, are smaller, and one bite is all it takes to reduce the plant to stubble. Cattle, especially, tend to graze severely, so don’t get too caught up in how much they take off. Strive for 50 percent use, and allow for regrowth. For some sites on dry ranges, this will mean one grazing event per year. For areas with more moisture, you might be able to return every 15 to 30 days for another grazing event.

Monitoring

This is the most neglected part of range management, and the most important. A good monitoring system will allow you to check how your management decisions are working on the ground. It will allow you to determine, for instance, if a particular grazing plan is having the desired effect over time. A monitoring plan will often involve a few important evaluation criteria, such as plant species composition, percent cover, and frequency of species. By comparing these measurements over time, you can start to see trends, and by comparing them to your grazing system, you can alter and adjust where you need to in order to arrive at your goals. To obtain more detailed information on rangeland monitoring contact Lee Rinehart at ATTRA at 800-346-9140.

Overgrazing

It is important to remember that overgrazing is not really a function of how many animals are on a pasture, but how long they remain there. In grazing management, time is the most important factor to consider in establishing a grazing system for sustained forage production. Continuous grazing allows livestock to selectively graze the most palatable plants over and over. The problem with this isn’t necessarily in the selective grazing activity, but in the fact that the grazed plant does not get the time to regrow before it is grazed again. New growth is more palatable and contains more nutrients than older growth, so animals will come back for a second and third bite as long as they are in the pasture, resulting in the most palatable forages being killed out.

A grazing system should allow the animal to be in the pasture long enough to take only that first bite. Frequent movement from pasture to pasture is a way to ensure that all plants have ample time to re-grow after grazing. In addition, for pastures with adequate water during the growing season, a very high stock density encourages animals to graze the pasture more uniformly than if the pasture was lightly stocked. In this situation the “weedy” species are being grazed at the same intensity as the “good” species.

Managing for Drought

Drought is a natural ecosystem process. The concept of an “average” or “normal” precipitation or temperature is a fabrication that humans use to try to understand complex systems and attempt to predict behaviors and outcomes. Whether in a humid zone or an arid environment, a producer will experience relative wet and dry years. Dealing with the dry years is a real challenge to livestock operations that rely on water to grow the plants and recharge the aquifers and streams that feed the animals. Having a drought plan is a very important component of a well-thought out farm or ranch management plan.

A drought-management option that deserves serious consideration is for a producer to maintain cow numbers at 75 percent of carrying capacity for “normal” years, and utilize the extra forage in wet years for high value animals such as stockers. In dry years the pastures will be better able to accommodate current cow numbers. Another option is to slow down rotations during dry years, thereby allowing more paddock or pasture rest time. This option can be effective especially when the herd is split between different pastures to minimize the impact on drought stressed plants.

References

Hatch, S. and J. Pluhar. 1993. Texas Range Plants. College Station: Texas A&M University Press.

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Permalink How can I deal with heat stress in poultry?

B.L.
Texas

Answer: Heat stress in poultry can be very serious, with layers being particularly susceptible. Birds will reduce their feed intake a great deal, since most of the energy in their feed is converted to body heat and reducing intake helps reduce heat stress. This reduction in feed intake means that egg production declines rapidly and may stop altogether.

Use of fans and misters in the poultry house is important in cooling the birds. However, misters should not be used to the point where humidity in the house is too high. Litter is also a source of moisture and needs to be managed so that humidity in the house is no more than 70% (1). Reducing stocking density can also help reduce the number of birds producing heat.

Fortification of water with vitamins and electrolytes is wise, especially when feed intakes are low due to hot weather. You can buy products like Merrick's Blue Ribbon Poultry Electrolyte Pack for this purpose.

Increasing nutrient intake during heat stress, by changing the feed specification, may have an adverse affect on survivability, but increasing the digestibility of nutrients and the use of specialist micro ingredients has been shown to have benefits.

The principal nutrients to consider are (1):

• Proteins and amino acids: nutrient digestibility should be increased rather than nutrient density, minimize excess protein and balance amino acids and minimize the crude protein level in the diet.
• Energy: the diet should be supplemented with fat rather than carbohydrate. Increasing the energy density of the diet will increase growth rate but will also increase heat output.
• Vitamins and minerals: certain vitamins are known to have a positive effect on the birds’ response to heat stress including Vitamin E, D, A, C, B2 and nicotinic acid. Under no circumstances should vitamins be withdrawn from the diet. A product such as Fertrells Nutri-Balance premix for feed may be useful for this.

As temperatures rise, the bird has to maintain the balance between heat production and heat loss, and so will reduce its feed intake. Reduced feed intake is the main cause of poor performance at high temperatures and the feeding practices below have been shown to have a positive effect on survivability and performance of birds experiencing heat stress (1):

• Ensure good physical quality of feed (crumb, pellets or mash) to encourage appetite. If floor space allows add extra feeders.
• Feed should not be stored for longer than one week to reduce the possibility of mycotoxin build up.
• Encourage eating at cooler times of the day as it takes 2-4 hours after feeding before the maximum energy is generated and the bird must dissipate the metabolic heat generated.
• Remove feed 4 to 6 hours prior to an anticipated heat stress period. Birds should not be fed or disturbed during the hottest part of the day.
• Dim the lights while feeding—low light intensity during periodic feeding reduces activity which reduces heat load.
• Reduced feed intake can increase susceptibility to calcium tetany. To ensure adequate calcium is available for eggshell production, feed oyster shell grit as a scratch feed. Feeding 1.5g of oyster shell grit per bird (.05 ounce, or about a third of a teaspoon) will replace this.

Reference:

1) Cockshott, Ian. No date. Hot weather broiler and breeder management: Ian Cockshott, Technical Service Manager for Ross in the Middle East & Africa looks at practical ways to manage stock in hot weather. Aviagen Technical Note. www.aviagen.com

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Permalink Where can I find information on crop insurance for transitional and organic production?

M.P.
Kansas

Answer: In Kansas, Multi-Peril Crop Insurance (MPCI) program is available. The Multi-Peril Crop Insurance Program (MPCI) is available for organically grown insurable crops. Acreage in transition to organic and acreage in buffers is also insurable. Federal Crop Insurance coverage, and thus insurance premiums, is based on average yield, numbers of acres per crop, and desired percent of reimbursement. To figure the terms under which a particular crop can be covered, two situations can be relevant. In the first, a producer reports production for each unit of production (field/crop) for up to 10 continuous years. An average of the data is the base yield that will be used in figuring insurance coverage. If 10 years of data are not available, a figure based on the historic county average will be used instead. New farmers can claim 100% of the historical yield average; existing farmers can only claim 65% (an incentive for real records to come into the office). Organic farms are not segregated or treated uniquely as far as historic yield averages are concerned.

To date, there is no reimbursement premium for organic crop production. Policy payments are based solely on yield reduction, acreage affected, and average conventional commodity price. The USDA Economic Research Service is collecting data on prices for organic crops, but has not collected enough data to have price averages for organic crops. So, for now, organic producers will be compensated for the loss of yield and acreage, but only at average conventional prices.

Organic producers need to apply for MPCI using a "Written Agreement," which is a request for exception, unless RMA currently covers the crop in the county that is being requested to be insured. To write a Written Agreement, a producer must first find a crop insurance agent. That agent will fill out a special form and work with RMA to write the agreement. The specific wording in RMA materials states that "If a Written Agreement is not requested for organic farming practices, loss adjustment procedures for conventionally grown crops will be applicable. Appraisals for uninsured causes of loss will be applied when conventional farming practices would have prevented damage due to insects, disease, or weeds." The use of a Written Agreement supersedes the status quo and acknowledges the unique practices involved in organic production.

Coverage for organic and transitional farming practices is available for all crop insurance plans, including the catastrophic risk protection (CAT) program and pilot programs if they are available in the state and county. Unfortunately, organic producers will continue to have to pay 5% more than their conventional counterparts and will also, in most cases, continue to receive loss payments at the rates set for conventional crops. Also, organic producers will not have the option to purchase conventional crop insurance. Organic producers must identify themselves as such when applying for insurance and not doing so will present a significant risk of not obtaining payments for catastrophic events.

A fact sheet on crop insurance for Organic Crops (PDF/ 21K) is available for mid-Atlantic and Northeastern states. Be aware that this fact sheet is from a different regional office than the one that serves you, and the specifics may vary in your region. For more information, contact your regional RMA office in Topeka. Contact:

Rebecca Davis
Director, Topeka Regional Office
3401 SW Van Buren, Suite 2
Topeka, KS 66611
(785) 266-0248
Fax: (785) 266-2487
E-Mail: RSOKS@rma.usda.gov

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Permalink How do I determine the stocking rate for a grass-based dairy?

C.S.
Oklahoma

Answer: Cattle are selective grazers. If given a choice they will only eat the highest quality, most palatable plants in the pasture. In order to ensure that plant biodiversity and high nutritional status is maintained in the pasture it is necessary to set up a grazing management system to better control livestock grazing. The elements of controlled grazing are (1) timing and (2) intensity of grazing. This means controlling the number of animals and how long they are in a pasture.

Consider developing a rotational grazing system to take full advantage of the benefits of nutrient cycling as well as the ecological balance that comes from the relationships between pastures and grazing animals. High density stocking for short periods helps to build soil organic matter and develops highly productive, dense, resilient pastures. For more information see ATTRA’s Rotational Grazing and Paddock Design, Fencing, and Water Systems for Controlled Grazing. Also available is Jim Gerrish’s Management-intensive Grazing: The Grassroots of Grass Farming, available from Green Park Press.

A rotational grazing management plan need not be complex. It merely has to direct the grazing animal to eat when and where you want them to in order to keep the plants in their growing (vegetative) stage. The basic principles of rotational grazing management include:

1. proper timing of grazing (corresponding to plant physiological stage)
2. proper intensity of grazing (duration on the pasture)
3. residue or plant height after grazing.

In order to efficiently utilize the dry matter available, a rotational grazing system should be implemented. Rotational grazing allows for more effective forage utilization by increasing herd size on smaller paddocks for a shorter time, thereby decreasing grazing selectivity and giving the farmer more control on what and when the livestock eat.

It is important to allow the pasture plants to get to sufficient height prior to turning the cattle onto the pasture. By waiting until the grass is 5 to 10 inches high, depending on species, the roots have become well developed and the plants can handle defoliation. Grazing intensity, or duration, can be taken care of by designing a suitable rotational grazing system. Rotational grazing, as the name implies, involves moving the cattle periodically from pasture or paddock to paddock. For instance, a good rule of thumb is to split a pasture into 10 or more paddocks (see guidelines for number of paddocks and paddock size below) with electric wire or electric tape, and stock each paddock heavily for a short amount of time. By doing this you are forcing the cattle to eat all that’s there, including weedy plants they might otherwise not eat. However, before the animals eat the plants to the ground, you move them to the next pasture. This takes into account the third principle. It’s important to leave several inches of grass to allow adequate leaf area for subsequent regrowth. Depending on the species, you will need to leave from 2 to 6 inches of plant stubble at moving time. An 11-paddock rotational grazing system that allows animals to graze each pasture for 3 days will give each paddock 30 days of rest (These figures are for planning purposes, and it is recommended to move according to forage height rather than by the number of days on pasture). Most grasses will need 15 to 50 days of rest between grazing events to allow adequate regrowth, depending on season, moisture, and plant type.

Calculating Paddock Size and Number

Two questions that will immediately come up for someone contemplating a rotational grazing system are (1) how many paddocks should I have, and (2) how big should the paddocks be? Essentially, answers to these two questions can be easily acquired by utilizing the following formulas:

To calculate the number of paddocks needed, use the following formula:

Paddock Number = Rest Period (days) /Grazing Period (days) + number of animal groups

Example:

Paddock Number = 30 days / 2 days + 1 = 16 Paddocks

Then, to calculate the size of each paddock in acres, use this formula:

Paddock Size = Daily Herd Forage Requirement X Days in Grazing Period / Lbs. Available Forage per Acre

Example:

Considering that growing steers will generally consume around 2.5% of their body weight, we will estimate the intake of one hundred 700 pound steers to be 17.5 pounds per animal per day, times ten animals equals 1750 pounds daily herd forage requirement. If the animals will be in each paddock for two days, and the available forage in the paddock is 2000 pounds per acre, then,

Paddock Size = 1750 X 2 / 2000 = 1.75 acres

Therefore, for a herd of one hundred 700 pound steers, and grass availability of 2000 pounds per acre, you would need 16 paddocks of 1.75 acres each, allowing for two days of grazing in each paddock before moving them to the next paddock. It is very important to realize, however, that 2000 pounds per acre is not the total productivity of the paddock, but reflects only the amount of forage the animals will be allowed to consume. A dense pasture in good condition will produce approximately 400 pounds of forage for each inch of plant height. So if you plan to begin grazing when the grass is 10 inches tall, and move the cattle when the grass is 5 inches tall, you should only calculate the 5 inch difference in height in your paddock size calculations. In our example, 400 pounds per inch X 5 inches = 2000 pounds per acre of available forage.

The figures and interpretations in this example are highly variable, and your situation will likely be different from this or any other grazing plan. This example is intended to familiarize producers with the basics of developing a rotational grazing system.

Overgrazing

It is important to remember that overgrazing is not really a function of how many animals are on a pasture, but how long they remain there. In grazing management, time is the most important factor to consider in establishing a grazing system for sustained forage production. Continuous grazing allows livestock to selectively graze the most palatable plants over and over. The problem with this isn’t necessarily in the selective grazing activity, but in the fact that the grazed plant does not get the time to regrow before it is grazed again. New growth is more palatable and contains more nutrients than older growth, so animals will come back for a second and third bite as long as they are in the pasture, resulting in the most palatable forages being killed out.

A grazing system should allow the animal to be in the pasture long enough to take only that first bite. Frequent movement from pasture to pasture is a way to ensure that all plants have ample time to re-grow after grazing. In addition, for pastures with adequate water during the growing season, a very high stock density encourages animals to graze the pasture more uniformly than if the pasture was lightly stocked. In this situation the "weedy" species are being grazed at the same intensity as the "good" species.

Determining Forage Yield

Forage yield can be determined with a (1) pasture ruler or (2) a rising plate meter. A pasture ruler is just that; a ruler calibrated in inches placed on end at ground level, with forage height measured in inches. A rising plate meter measures density as well as height. A 20 X 20 inch plate weighing 2.6 pounds is dropped on a rule at waist height. For this measure in Iowa and Missouri, each inch of forage height equals 263 lb/ac DM, and has been verified by numerous clip and weigh field studies. This measure should be calibrated for local conditions by clip and weigh method to obtain accuracy.

A good rough estimate is 300 pounds of dry matter per acre per inch on a ruler. This measure is likely to have a 50 to 80 percent accuracy depending on if you have calibrated your measurement procedure. Jim Gerrish’s values range from 150 pounds per acre per inch in a fair stand to 600 pounds per acre per inch in an excellent stand as determined by clipping and weighing numerous quadrants and comparing them to sward heights (Gerrish, 2004). The vast differences in the above estimates reflect differences in pasture types. For example, bermudagrass will most likely be different from bromegrass when measuring stand density with a ruler or rising plate meter.

References and Resources

Forage Information System
http://forages.oregonstate.edu/index.cfm
A comprehensive website for forage-related topics, including publications, educational opportunities, and professional resources. Maintained by Oregon State University.

Grazing Systems Planning Guide
Kevin Blanchet, University of Minnesota Extension Service
Howard Moechnig, Natural Resources Conservation Service
Minnesota Board of Water & Soil Resources,
Jodi DeJong-Hughes, University of Minnesota Extension Service
University of Minnesota Extension Service Distribution Center,
405 Coffey Hall, 1420 Eckles Avenue, St. Paul, MN 55108-6068 order@extension.umn.edu
Delineates the components of a grazing system by taking the farmer through the grazing management planning process. You can also view/download it at www.extension.umn.edu/distribution/livestocksystems/DI7606.html.

Management-intensive Grazing: The Grassroots of Grassfarming
Jim Gerrish, Green Park Publishing
This book can be obtained through The Stockman Grassfarmer’s Bookshelf at 800-748-9808.
The industry-standard for growing and managing pastures for sustained livestock production.

Southern Forages
Donald M Ball; C S Hoveland; Garry Lacefield
Altanta, Ga.: Potash & Phosphate Institute: Foundation for Agronomic Research, ©1991. Third Edition 2002.

Pastures for profit: A guide to rotational grazing
Cooperative Extension Publications, 45 N. Charter St., Madison, WI 53715
www1.uwex.edu/ces/pubs/
Grazing ecology, and setting up a rotational grazing system.

The Economics of Organic and Grazing Dairy Farms
Regional Multi-State Interpretation of Small Farm Financial Data from the Fourth Year Report on 2003 Great Lakes Grazing Network Grazing Dairy Data. Madison, WI: UW Center for Dairy Profitability. Kriegl, T. 2005.
Fact Sheet #1: Project Overview
Fact Sheet #2: Comparing the Top Half with the Bottom Half of Graziers
Fact Sheet #3: Comparing Herds by Size. Less than 100 Cows vs. 100 Cows or More
Fact Sheet #4: Comparing Seasonal Calving with Non-seasonal Herds
Fact Sheet #5: Grazing vs. Confinement Farms.
Fact Sheet #6: Preview of Financial Performance of Graziers by Breed
Contact: Tom Kriegl at 608-263-2685 or
277 Animal Sci Bldg
1675 Observatory Dr.
Madison, WI 53706
http://cdp.wisc.edu/
Comprehensive research project comparing conventional and pasture-based dairy farms in the Midwest. An excellent resource for dairy farmers considering a transition to organic and/or pasture-based production.

Organic Dairy Farming: A Resource for Farmers (2006)
Jody Padgham, editor.
Midwest Organic and Sustainable Education Service
PO Box 339, Spring Valley, WI 54767
www.mosesorganic.org
715-772-3153

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