Drought: Weathering Troubled Times - University of Wyoming
College of AgricultureCooperative Extension ServiceAgricultural Experiment Station a A parched Wyoming eagerly drank the recent spring precipitation. However, the grim news is that one of the worst dry spells in the state’s history is still a reality. Agriculturally speaking, drought means hard times for ranchers, farmers, livestock, crops, gardeners, and the economy. Ultimately, it impacts almost everyone. In this special section, University of Wyoming College of Agriculture faculty members and Cooperative Extension Service educators join forces to help advise drought victims about how to best manage and recover their operations and lands and about how to be resilient as they weather tough times.
Page 2 Spring, 2003 UW College of AgricultureDry weather calls for summerSteve Paisley mals is the safest route. WhenUW Cooperative Extension feeding, introduce the high-Service Specialist, Department nitrate feeds gradually. Cattleof Animal Science do have a limited adaptation to higher nitrate levels. By in-A lthough parts of the state received much-neededmoisture during recent troducing feed slowly, one can reduce but not eliminate the risk of having problems. Also,months, perhaps enough to at making sure the overall rationleast “green up” this spring, is balanced by providing ad-there are still no guarantees of equate energy (small amountsadditional summer moisture of supplemental grain) will re-to maintain grass or replenish duce the risk.the already low reservoirs or If forced to feed bales oflivestock water sources. While high-nitrate feed, introducethe recent moisture will allow them slowly, feeding some ofnearly everyone to turn out both the high-nitrate and safethis spring, there are a few is- hay each day. Generally feedsues to consider as the sum- the high-nitrate feed first fol-mer progresses. lowed by the safe feed. There is still the risk that some cowsWater Concerns will eat only the high-nitrate As stock ponds remain hay. For example, dominantlow, the quality of the remain- Pictured are a cow and spring calf. cows may push the thin oring water becomes a nutrition timid cows away from the bet-and health concern. In the fall, ings suggest that sulfate lev- nitrate susceptible forages, pro- are that nitrate levels of 6,000 ter hay, forcing them to eatadult cows typically require 7 els less than 1,000 ppm are ducers can reduce the risk ppm (1 percent KNO3) or less only the high-nitrate forage. Toto 11 gallons of water per day generally safe, with 1,000 to through livestock and forage are generally safe. Nitrate lev- reduce the risk of this, sort thedepending on outdoor tem- 2,500 ppm levels causing re- management. els of 6,000 to 9,000 ppm (1 to cattle into thin/weak cows andperatures and stages of pro- duced performance and occa- 1.5 percent KNO3) are poten- adult cows.duction. Ewes typically require sional cases of polio. Levels ap- Nitrate-Susceptible tially toxic and should be fed When managing high-ni-2 to 3 gallons per day. Poor proaching 2,500 to 4,000 ppm Forages with caution. Nitrate levels over trate forages, it is better to feedquality stock water can actu- of sulfate indicate very poor In most cases forages to 9,000 ppm (1.5 percent KNO3) frequently and not allow cattleally decrease water intake, put- water with definite reductions be most concerned about are are extremely dangerous and to go hungry. Also, it is impor-ting additional stress on an ani- in animal performance and an drought-stressed warm season must be diluted and blended tant to manage feedingmal. Most water tests report increased occurrence of polio. annual forages such as sor- with other feeds. When testing closely, especially during se-Total Dissolved Solids (TDS) as Additional concerns with ghum/sudan “cane” hays and hay for nitrates, be sure to vere weather. If cattle go with-a measure of the concentration poor water quality include millet hays. Weed species such sample from at least 10 bales out feed for a day, they mayof dissolved salts. TDS levels mineral interactions and sec- as kochia, lambsquarters, sun- since there is a lot of variation go back and pick throughless than 3,000 parts per mil- ondary mineral deficiencies flower, and pigweed can also in nitrate levels from bale to coarse stalks from previouslion (ppm) are generally safe that can occur with high TDS accumulate nitrates, so emer- bale. It is generally safer to feed feedings. Those lower stalksfor livestock. Levels of 3,000 to and high sulfate water. High gency feed resources should susceptible forages to non- are where most of the nitrate5,000 may not dramatically levels of sulfate or other min- be watched closely. Finally, pregnant animals, and it is located, increasing the riskaffect adult livestock, but erals can compromise an under extremely stressful con- should be remembered that of nitrate problems.young, growing livestock may animal’s immune system, ditions, additional crops such nitrates remain in the plant no Finally, be aware of allhave poor performance and leading to an increased inci- as corn, wheat, oats, and bar- matter how long hay is stored. sources of nitrates. Somecharacteristic looseness. TDS dence of health problems. It ley can also accumulate ni- stock water sources can belevels of 5,000 to 7,000 should is always a good idea to trates. From a management Feeding high in nitrates, adding to thenot be offered to pregnant or sample and test water sources standpoint, the plant nitrates Recommendations risk. Also, poor water sourceslactating animals. to avoid future problems. are generally located in the Once the nitrate level of a can reduce a herd’s water con- Another water quality lower 1/3 of a stalk. Raising the forage is known, one can sumption, also adding to theconcern is the sulfate level of Concerns of High cutterbar when swathing or manage accordingly. The best problem.water. High iron and sulfate Nitrate Forages reducing the grazing pressure situation is to keep the overall While there are risks asso-levels can affect trace mineral During Drought so animals are not forced to ration nitrate level below ciated with using high-nitrateabsorption, especially copper, While concerns about ni- graze the lower portion of 6,000 ppm nitrate (1 percent feeds, weather conditions, haybut high sulfate water can also trates typically occur during the stalks will help reduce the ni- KNO3). This may mean blend- availability, and hay prices mayincrease the risk of fall and winter when produc- trate concerns. ing or mixing hays. When limit any other alternatives.polioencephalomalacia or po- ers are purchasing and feeding feeding nitrate-susceptible for-lio. Symptoms of polio in Nitrate Testing ages, the safest method is to Following a few basic guide- hay, it may be just as impor- lines and managing cattlecattle include blindness, signs When testing forages for tant to think about nitrate con- tub grind and blend with low- closely will definitely reduceof nervousness, and uncoor- nitrate levels, pay close atten- cerns early in the year and re- nitrate hay. If a producer is the risk of nitrate problems.dinated movement. South tion to how the nitrate levels duce the risk of nitrates unable to tub grind, some im-Dakota State University re- through forage-selection deci- are reported. Depending on portant management consid- Supplementationcently reported results from sions, harvesting, and grazing the lab, nitrate levels may be erations result. Strategiesan ongoing project evaluating described as nitrate (NO3), ni- management. Although dry, As mentioned before, Catering the Supplementwater sulfate levels. Based on trate nitrogen (NO3N), or po- stressful weather increases the feeding susceptible forages to to the Situation. One of thetwo years of data, their find- tassium nitrate (KNO3). Gen- risk of nitrate accumulation in growing (non-pregnant) ani- common misconceptions con- eral nitrate recommendations
UW College of Agriculture Spring, 2003 Page 3herd management cerning the use of supple- fordable supplements are of- SITUATION 2: Early Weaning ments is the “one-size-fits-all” fered, summer supplementa- Adequate to limited hay/ Raising the cutterbar Another important sum- mentality. In reality, there is a tion programs are going to be forage available, and the mer management consider- wide range of responses to an option to consider. It is im- forage is not providing when swathing or ation is early weaning, espe- enough nutrients to supplements, depending on a portant not only to capture all meet a cow’s reducing the grazing cially if summer rains do not number of factors. Some of of the benefits that are avail- come and forage becomes these factors include the qual- able through drought assis- requirements pressure so animals limited. Studies involving early This situation describes ity of the forage being grazed, tance programs but also to are not forced to weaning indicate that remov- the quantity or availability of make the supplement fit the common conditions when ing a calf during mid to late the forage, the nutrient re- situation to help get the de- cows are close to calving or graze the lower summer reduces a cow’s for- have just begun calving and quirements of the animal be- sired results. When evaluating portion of the stalk age requirement by 35 to 50 ing supplemented, the range supplements, there are are being fed a medium-qual- percent. This reduced forage amount of supplement being three general situations to con- ity meadow hay. The in- will help reduce the requirement may help buy creased energy demands of fed, the source and quantity sider. Each has its own unique nitrate concerns. time, allowing cows to stay on of TDN or energy being sup- solution provided by the late gestation and early lacta- summer grass rather than hav- plied by the supplement, and supplementation program. tion are greater than what is ing to bring pairs home early. the level and quality of the provided in the forage. Often If cows appear thin, early SITUATION 1: There is the first limiting nutrient in protein being offered in the situation would tend to either weaning may also help add adequate forage, but these situations is energy, fol- supplement. During drought increase forage intake or at low forage quality is weight and condition while conditions, the wrong match lowed closely by protein. An least maintain the current for- cows are still on grass. Data limiting intake. additional supplement is of supplement to the situation age intake. One way to stretch from the University of Wyo- This is typically the situa- needed to provide extra en- can have very negative results. the available forage is by feed- ming found that following tion producers face when ergy and protein to meet the For example, feeding small ing supplements that are rela- early weaning, cows gained cows are grazing winter range. nutrient demands of a cow. amounts of a high-protein tively high in energy and low approximately 85 pounds dur- If the pastures have been The best supplement for this supplement (30 percent CP and in protein. These high-energy, ing an 82-day period while saved exclusively for fall and situation is a medium-protein above) to cattle with very lim- low-protein supplements cows still lactating during that winter grazing, there are typi- supplement that provides en- ited forage may not be the best would not work in Situation 1 same period lost an additional cally adequate amounts of for- ergy as well as protein. There match of the supplement for the where the goal is to increase 40 pounds. This occurred age for the herd. The lower are several supplements that situation. Providing high-quality intake and digestibility. They while cows and cow/calf pairs quality of the forage and slow fit this situation well such as supplemental protein typically are designed to replace forage were grazing relatively low- digestion/long retention times higher energy 20s cubes, liq- improves the digestibility of the and actually decrease forage quality range forage in Sep- in rumen limit the amount of uids, blocks, etc. High-fiber forage and increases the intake intake while maintaining ad- tember and October. The early forage cows can eat. As the byproduct feeds also work of low-quality hay. In the situa- equate energy and protein. It weaned calves grazing high- weather turns colder and fe- extremely well in these situa- tion described above, the prob- has traditionally been called a quality meadow regrowth tal growth begins to increase, tions. Byproduct feeds include lem is lack of forage, not its qual- “negative associative effect” gained similarly to those cattle need to increase intake wheat midds, corn gluten feed ity or digestibility. Supplying a when supplements reduce for- calves still nursing their dams to continue to meet their en- pellets, distiller’s grains, beet lower-protein, higher-energy age intake, but in this situa- over this period of time. This ergy needs. Providing small pulp pellets, and probably the supplement may help to meet tion, where forage is limited, management strategy can amounts of a digestible pro- most heavily used medium- a cow’s energy needs while also it works to the producer’s ad- also have major implications tein source will improve diges- protein supplement, alfalfa reducing forage consumption. vantage. High-energy, low-pro- on nutritional costs and the tion of low-quality forage, im- hay. The benefit of these high- As drought assistance pro- tein supplements are typically breed-back efficiency of young proving passage rate and in- fiber byproduct feeds are that grams continue and more af- grain, grain-based range females as 3 and 4-year-olds. creasing forage intake. This they provide needed energy cubes, grain/byproduct mix- While it may not be fea- example of a “positive asso- while also containing ad- tures, etc., with protein levels sible to wean all of the calves ciative effect,” providing a equate protein. They have a below 20 percent. Again, the early, consider weaning a por- small amount of supplement very positive effect on energy While there are risks to increase forage consump- net effect is reducing forage tion of the spring calves early. intake because they can be fed intake while maintaining ad- First and second calf heifers associated with using tion and improve the energy at 3 to 6 pounds daily, and equate energy and protein lev- would definitely benefit from and protein status of a cow, cattle continue to maintain the high-nitrate feeds, has been used for decades. A els for cattle. having the calves removed a same level of forage intake. The three examples de- month to two months early. weather conditions, protein supplement can be of- They are essentially an energy scribed may over simplify the Weaning in two groups may fered as high-protein range and protein “boost” that hay availability, and cubes or pellets, blocks, lick situations. There are obviously also help reduce the stress on doesn’t affect forage intake. several types of supplements, weaning facilities and allow hay prices may limit tubs, liquid supplements, etc. The key points are that the SITUATION 3: Cattle several ways of delivering the more time to address the any other protein level needs to be rela- performance and forage supplements, and additional health and management of alternatives. tively high (30 percent CP and quality are adequate, management considerations. the calves during weaning. It higher), the supplement needs but forage supply is However, they are a step be- may also provide some flex- Following a few basic to be fed or offered in small limited yond the “one-size-fits-all” ibility in marketing calves. This is the situation that mentality with supplementa- Early weaning may be an guidelines and amounts, and the protein many producers were faced tion programs. For additional important consideration every needs to be a highly digestible, managing cattle good quality one with rela- with last summer. Cattle were help or ideas, visit with a Co- year, especially with young in good condition, but there operative Extension Service cows. Getting cows in good closely will definitely tively low levels of NPN to get was little forage left for them educator. He or she can pro- shape before winter sets in is maximum benefit. reduce the risk of to graze. Feeding high or mid- vide additional information important in maintaining ad- protein supplements in this and help work through some equate condition and in improv- nitrate problems. of the choices. ing reproductive performance.
Page 4 Spring, 2003 UW College of AgricultureNot much water? Water-wise choices Karen L. Panter properly. Always keep in mind Cooperative Extension Service that any new plantings will Specialist, UW Department of require consistent moisture Plant Sciences until they are established, es- pecially during the winter. T he drought situation has hit Wyoming hard. Even though there may still be snow Step 1 – Developing a Landscape Plan Spend some time plan- on the ground in some places, ning and designing on paper. the situation is that many Analyze the site, taking into ac- Wyoming cities will put water- count existing structures, ing restrictions in place this other plants, and neighbors. year. Some already have. Then decide what areas are Many believe people needed: turf area for the kids, should practice water conser- a vegetable garden, a center vation all year long inside and for entertaining, or a dog zone. outside homes rather than just in the landscape during the Step 2 – Limiting Turf growing season. Try simple Areas things like washing only full Note that this does not say loads of laundry or dishes, eliminate turf areas. For areasGazania linearis – Gazania with little to no foot traffic, keeping a pitcher of water in the fridge, cutting bath water consider groundcovers such as down a gallon or two, and cut- carpet bugle (Ajuga), thyme ting down shower time a (Thymus), vinca (Vinca minor), minute or two. These will all nettle (Lamium), or sweet go a long way towards saving woodruff (Galium). For heavily the most precious western re- used areas, consider mixtures source – water. of turfgrasses. For areas that In the landscape there are may be tough to maintain and all sorts of wonderful plant mow, consider perennial orna- types from annuals to ever- mental grasses such as feather greens that don’t require reed grass (Calamagrostis much water. And for plants acutiflora), northern sea oats that require a bit more irriga- (Chasmanthium latifolium), tion, there are watering sys- blue oats (Helictotrichon tems and mulches available to sempervirens), or switch grass keep the water in the ground (Panicum virgatum). where the plants need it. Keep in mind that turf ar- Years ago, Denver Water eas help to cool down the en- coined the term “xeriscape” to vironment, soften the land- denote landscaping with low- scape, and provide essential water-using plant material. oxygen. Using rock or gravelCerastium tomentosum – Snow in Summer (No, it’s not pronounced mulch near a home may end “zeroscape.”) Unfortunately, up heating the area. Any sav- many people think this means ings in water might be offset gravel and cactus, but nothing by air conditioning costs in- could be farther from the side. truth. Others have used the Step 3 – Selecting and term “water wise.” Either way, Zoning Plants there is a definite process in- Appropriately volved in landscaping to cut Put the right plants in the down irrigation needs. right places. Group plants with There are seven steps in- similar water requirements to- volved in setting up a water- gether to make irrigation sim- wise landscape or xeriscape. pler and more efficient. Look These steps are, briefly: 1) for microclimates around developing a landscape plan, structures. Every yard or land- 2) reducing turf areas, 3) im- scape will have shady areas proving the soil, 4) selecting that stay moister than south- appropriate plants, 5) mulch- facing zones. Use plant mate- ing the soil, 6) irrigating effi- rials that will fit these particu- ciently, and 7) maintaining lar areas.Helictotrichon sempervirens – Blue Oat Grass
UW College of Agriculture Spring, 2003 Page 5important for gardens and landscapes Step 4 – Improving the Step 6 – Irrigating Step 7 – Maintaining Soil Efficiently Properly This is probably the most Note that this does not say A no-maintenance land- important step in any land- stop watering. Water accord- scape is almost nonexistent, scaping, xeric or otherwise. ing to area and plant type as but low maintenance is pos- Before any plants are put in well as weather patterns. Use sible, depending on the plant the ground, add good quality drip irrigation where possible material. Some xeriscape or organic matter. Put a layer for annuals, perennials, and water-wise gardens may need about two inches thick on the vegetables. Other types of as much maintenance as a area to be planted and then watering systems should be more traditional garden. Such till or spade it in to a depth of used for large trees and shrubs routine tasks as weeding, about six inches. Also, core as well as turf areas. These can deadheading, fertilizing, and aerate lawn areas at least once include overhead sprinklers occasional mowing will still a year. This allows better wa- Perovskia – Sage Calamagrostis acutiflora – and automatic systems. Re- need to be done. ter and air penetration to the Feather reed grass member to change the auto- The tables below list some grass root systems. Leave the landscaping. Good quality or- ganic mulches (gravel, rock, matic clock according to the suggestions for water-wise cores on the turf since they ganic mulches (bark, straw, etc.) can also be used but can weather and season. “Set and plant materials from trees to will add nutrients back to the etc.) keep moisture in the soil, be warm. The type that should forget” is too common and is annuals and even a few shade area as they break down. minimize evaporation, moder- be used (inorganic or organic) not appropriate. Whatever sys- plants. ate soil temperatures, mitigate tem is used, make sure it is Step 5 – Using Mulches depends on the landscape de- freeze/thaw damage, and add sign and the long-term goals functioning properly and is This is arguably the sec- organic matter back into the for the area. not clogged or split or leaking. ond most important step in soil as they decompose. Inor- Trees Groundcovers Acer ginnala deciduous amur maple Antennaaria dioica pussytoes Crataegus crus-galli deciduous cockspur hawthorn Cerastium tomentosum snow-in-summer Gymnocladus dioicus deciduous Kentucky coffeetree Polygonum affine fleece flower Juniperus scopulorum evergreen Rocky Mountain juniper Santolina chamaecyparissus lavender cotton Pinus aristata evergreen bristlecone pine Sedum (many species) stonecrop Pinus ponderosa evergreen ponderosa pine Sempervivum sp. hens and chicks Pinus cembroides edulis evergreen pinyon pine Thymus pseudolanuginosus wooly thyme Prunus virginiana deciduous chokecherry Veronia pectinata blue woolly speedwell Quercus macrocarpa deciduous bur oak Grasses Shrubs Agropyron cristatum bunch turf grass crested wheatgrass Caryopteris x clandonensis deciduous blue mist spirea Bouteloua gracilis clump blue grama grass Ceratoides lanata or ornamental, turf Krascheninnikovia lanata deciduous winterfat Calamagrostis acutiflora ornamental feather reed grass Cercocarpus ledifolius deciduous mountain mahogany Festuca arundinacea turf grass tall fescue Cotoneaster apiculatus evergreen cranberry cotoneaster Festuca ovina glauca ornamental blue fescue Juniperis chinensis evergreen Chinese juniper Helictrotrichon sempervirens ornamental blue oat grass Juniperus communis evergreen common juniper Oryzopsis hymenoides ornamental Indian rice grass Juniperus horizontalis evergreen spreading juniper Juniperus sabina evergreen savin juniper Annuals Potentilla fruticosa deciduous cinquefoil Robinia neomexicana deciduous New Mexico locus Coreopsis tinctoria tickseed Eschscholzia californica California poppy Perennials Gaillardia pulchella blanket flower Gazania (several species) gazania Achillea sp. yarrow Gomphrena globosa globe amaranth Asclepias tuberosa butterfly weed Lavatera trimestris annual mallow Callirhoe involucrata wine cup Pennisetum setaceum rubrum purple fountain grass Centranthus ruber valerian Portulaca grandiflora moss rose Eriogonum umbellatum sulfur flower Portulaca oleracea purslane Gaillardia x grandiflora blanket flower Sanvitalia procumbens creeping zinnia Hemerocallis sp. daylily Zinnia angustifolia narrowleaf zinna Nepeta x faassenii catmint Oenothera missouriensis evening primrose Shade plants Perovskia atriplicifolia Russian sage Penstemon (some species) beardtongue Arctostaphylos uva-ursi evergreen shrub kinnikinnick Salvia (many species) sage Heuchera sanguinea perennial coral bells Sedum sp. stonecrop Mahonia repens creeping grape holly Tanacetum densum partridge feather Symphoricarpos x chenaultii chenault coral berry Vines Lonicera (some species) honeysuckle vine Parthenocissus quinquefolia Virginia creeper Polygonum aubertii silver lace vine
Page 6 Spring, 2003 UW College of AgricultureDrought affects livestock diseaseDonal O’Toole particularly dairy cattle, whenProfessor and Department concentrations exceed 1,000Head, UW Department of ppm. Concentrations in ex-Veterinary Sciences cess of 5,000 ppm will de- crease production in rangeMerl Raisbeck animals and may cause illnessProfessor, UW Department of and/or death.Veterinary Sciences Salt poisoning leads toLynn Woodard seizures and prostration. SaltProfessor, UW Department of poisoning/water deprivation isVeterinary Sciences especially hazardous during times of high temperatures.T hree years of drought in the high plains have hadan appreciable impact on the High levels of magnesium (greater than 250 ppm) may aggravate the problem. Thus,range of diseases that Univer- This is the brain of a steer with PEM. The arrows point to areas of damaged gray matter. Higher complete salt screens should magnification of the boxed area shows necrotic gray matter of brain.sity of Wyoming diagnosti- be requested when watercians at the Wyoming State which can be obtained from a ties suggest concentrations of during drought due to irritation samples are collected for test-Veterinary Laboratory (WSVL) county agent, to collect 10 less than 500 ppm as a safe caused by dust. Fine dust par- ing. One recent case occurredrecognize in Wyoming live- to15 sub-samples from each cutoff for water. If both feed ticles enter the airways and when yearlings were moved tostock. Many of these are just stack or load of hay. Results and water contain appreciable damage the lungs, setting the a pasture where they could notworse cases of what is seen in obtained from testing samples concentrations of nitrate, one scene for infection by micro- locate a water tank. The de-normal years, but some are collected by grabbing handfuls has to consider the contribu- bial agents. Feedlot and ranch hydrated yearlings developedunique to periods of extended here and there are unreliable tion from both sources. In operators sometimes use the constipation and/or diarrhea,drought. since they are likely to miss other words, subtoxic concen- term “dust pneumonia,” but weakness, emaciation, and aggressive behavior. SomeNitrate poisoning nitrate “hot-spots” in the hay. trations of NO3 in water com- this is not specific and the con- It is important to have testing bined with subtoxic concen- dition seen may have nothing died before finding water. A major risk during peri- done at a laboratory familiar trations in hay may result in to do with inhaled dust. One Some dehydrated steers thatods of drought is nitrate (NO3) with this type of analysis. For- toxicity. way to minimize losses is to found the water drank to ex-poisoning of adult ruminants. age nitrate analysis is differ- Horses are resistant to ni- give modified live vaccines for cess, developed convulsions,Drought stress exacerbates ent from the similar-sounding trate intoxication. Assuming viruses like BRSV with precon- and died. In another recentthe tendency of many plants nitrate-nitrogen test on water the hay is good in other re- ditioning shots. By contrast, episode, 130 cattle died in ato accumulate nitrate, particu- samples by environmental spects, moderately high NO3 killed products have, in some 48-hour period as a result oflarly oat hay and Sudan grass laboratories. It is recom- hay can be fed to horses. If the cases, increased the disease salt poisoning.hybrids that were fertilized in mended that samples be NO3 concentration is not too severity in BRSV outbreaks. Polioencephalomalaciaanticipation of normal mois- tested at the Wyoming Depart- high (less than 1.5 percent), it Stressed animals are more sus- (“polio” or PEM) due to high-ture. While it is a good idea to ment of Agriculture’s Analyti- can be diluted to acceptable ceptible to infections of all sulfate (more than 2,500 ppm)test hay before feeding it, it is cal Services Laboratory in concentrations with clean kinds. It is important to stick water is another disease exac-especially important during a Laramie [(307) 742-2984; ac- feed. Feed must be thoroughly with a good vaccination pro- erbated by drought. Sulfate isdrought. Nitrate poisoning cession forms available online mixed before serving (e.g., gram during a drought. concentrated in stock pondsimpairs the ability of blood to at www.wyagric.state.wy.us/ using a grinder) otherwise and sinkholes by evaporationcarry oxygen. The result is aslab/aslab.htm.] It is impor- some cattle may still get a Blue-green algae so that water sources thatsudden death, which may tant to understand how results toxic dose. Merely throwing poisoning were previously safe becomestrike a large number of adult are reported since there are out one bale of “bad” and two Blooms of toxic blue- deadly under drought condi-cattle in a herd at once with- several ways to express nitrate bales of “good” hay does not green algae leading to cattle tions. Like nitrate poisoning,out warning. In most cases, concentration. In fact, one constitute dilution. Fermenta- losses occur on rare occasions the sulfur contents of feed andcattle are found dead, and measure of a laboratory’s ex- tion may decrease NO3 con- in the High Plains. Blooms water are additives in causingtreatment is impractical. This pertise is whether its person- tent somewhat if there is suf- form on bodies of water un- the disease. In spite of itsis one of the more common nel make recommendations ficient soluble carbohydrate der conditions of heat, stagna- name, it has nothing to docauses of poisoning confirmed based upon results and offer present, but most Wyoming tion, eutrophication (high ni- with the infectious diseaseby the WSVL in cattle. Lower more than just a number. forages lack the necessary trogen and nutrients), low flow poliomyelitis in children –concentrations of dietary ni- The WSVL uses less than energy to fuel the reaction. rates, and a concentrating polioencephalomalacia is atrate may also cause abortion. 0.5 percent NO3 (measured as The probiotic feed additive wind. Toxic algal blooms lead technical term for breakdown Hay should be sampled the nitrate ion) as a “safe” cut- Bova Pro® (FarMor Biochem, to sudden death due to liver of gray matter in the brain,for nitrate testing after it is cut off for forage. Many authori- Milwaukee), based upon a pat- damage, shock, and/or central which is what happens in bothand cured. Use a bale corer, ented Propionibacterium bac- nervous system injury. This is dehydration/salt poisoning teria, is advertised to decrease a rare cause of loss in Wyo- and sulfate poisoning. rumen NO3 and blood meth- ming. When losses occur, the Ponds are the biggest emoglobin concentrations by death toll can be heavy and problem, but well water may 40 to 50 percent. Preliminary sudden. also be high in sulfates. Al- though PEM is normally a data looked promising when Dehydration-salt the product was introduced problem in spring and sum- poisoning and mer when water consumption several years ago. sulfate poisoning is greatest, it may occur in any Dust and pneumonia (“polio”) season when sulfate concen- Bovine respiratory disease, High levels of NaCl (com- trations are high or if animals especially due to bovine respi- mon salt) and/or water depri- are abruptly exposed to high- ratory syncytial virus (BRSV) vation are hazardous to live- sulfur waters. Clinically, ani-Three of 130 dead cattle that died of salt poisoning over a 48- and Pasteurella (Mannheimia) stock. Sodium may affect pro- mals become blind and showhour period in one herd in Wyoming are shown. bacteria, may be more serious duction in sensitive animals, nervous signs such as incoor-
UW College of Agriculture Spring, 2003 Page 7on the high plains dination and a goose-stepping ing large amounts of dense, and open-mouth breathing in Plants containing high con- The sudden switching of gait. Testing stock water is poor roughage may cause ex- the absence of coughing centrations of soluble ox- feeds or increases in grains important to prevent prob- tensive lesions in the mouth shortly after they are turned alates (Halogeton and grease- may lead to rumen acidosis lems. Cattle develop some tol- and throat, resulting in ab- out on fertilized or irrigated wood) are more toxic when and diarrhea. Drought-related erance to elevated sulfate wa- scesses of the head region. aftermath. This disease pre- ingested by sheep lacking acidosis is common when ters if they are introduced to Several episodes have oc- sents a challenge to producers adequate water. Locoweeds short feed inventories neces- it gradually. There is no cost- curred in which adult animals during periods of drought. remain toxic even in winter sitate more frequent switches effective method for removing had such severe oral lesions Most ranchers don’t move months. Cattle may consume or when some non-traditional sulfate from stock water. Haul- that they were unable to swal- cattle to meadows until after more locoweed during a feeds such as baker’s ing water may be the only low and lost weight or died heavy frosts, which lower the drought. Clinical signs are byproducts or dough (high car- option on some ranches with due to pus draining into the risk. During a drought this abortion, nervousness, and bohydrate sources) are added a high sulfate problem. lungs from mouth abscesses. may not be an option. Preven- brisket disease. Pine needle suddenly to rations. The pre- In one episode, 23 of 150 adult tative strategies include gradu- abortion cases may occur vention of abomasal impac- Salinity cattle belonging to one pro- ally adapting cattle to a pas- more commonly during tions, rumen acidosis, and Sodium and sulfate are ducer developed large, ture over 10 to 12 days, cut- drought as cattle will eat the hazards of unusual feeds cen- not the only elements concen- chronic, pus-filled facial swell- ting and windrowing the pas- needles more readily. ters on providing a proper trated in livestock water sup- ings. Cattle had large lymph plies by drought. A number of nodes due to secondary bac- different inorganic substances terial infections. Treatment cumulatively contribute to the was unavailing. No foxtail or property of water referred to other penetrating plant frag- as “salinity.” Simply stated, the ments were found, and the salinity of a water sample is owner was adamant that he what is left after the water is avoided foxtail stands when boiled off and organic com- haying. The owner ran the pounds are oxidized. Salinity cattle on an arid creek where may be indirectly measured as there were heavy stands of total dissolved solids (TDS) or greasewood (Sarcobatus conductivity. Although the re- vermiculatus). Due to the lationship between salinity drought and lack of forage, the and disease is not as clear-cut cattle probably grazed on as for sodium and sulfur, high- greasewood and developed salinity water does not sup- extensive wounds of the port productive animals. The These three horses have swelling of the brisket or shoulder area due to pigeon fever. mouth due to the stiff spines impact depends upon the of the plant. Opportunistic bac- class of animals and their wa- ture before turnout, and ex- Management of plant poi- diet. Rations should be bal- teria infected the wounds and ter requirements. For ex- posing less susceptible sonings centers on preven- anced to allow for optimal pro- created the clinical problem. ample, lactating dairy cows younger stock (less than 15 tion. Grazing management tein, mineral, energy, and Coarse feed can also result may be affected by as little as months old) or sheep to the involves the prevention of roughage contents. Roughage in abomasal impaction in 1,000 ppm TDS whereas beef pasture first. Ionophores such overgrazing by proper pasture should be of the proper den- cattle. Heifers in late pregnancy cattle may tolerate as much as as monensin will prevent or rotation and by reducing sity to allow for optimal gas- are at most risk due to the in- 5,000 to 7,000. High salinity reduce pulmonary emphy- stocking rates. Weed control trointestinal activity. Unusual creased nutrient demands of is more likely to result in pro- sema if fed in advance, but can be attained by proper feeds, while tempting at times, combining growth and gesta- ductivity losses than in clini- many cows won’t use the fencing, prudent application should be consciously avoided tion. Pregnant heifers develop cal disease and deaths. blocks and they are of no of weed killers, and mowing/ or viewed with skepticism. bloat, recumbency, and die value once clinical signs begin. plowing. If herbicides are Sudden feed switches should Coarse feed with large amounts of black Keep a close eye on cows for used, beware that some can be avoided. It is helpful to ac- Poor quality feed can lead fluid in the rumens and impac- a few days after a change to temporarily increase toxicity climate cattle to new rations to diseases when nutritional tions in the abomasum. lush meadows. and/or decrease the palatabil- slowly. contents are low and/or alter- Pulmonary ity of plants. nate feeds are abused. Feed- Toxic plants Pigeon fever emphysema (“cow Unusual feedstuffs The danger from poison- myositis in horses asthma”) ous plants is magnified during Feeding of unusual feeds A disease that is unusual Pulmonary emphysema drought. Overgrazing, aggra- or those of unknown quality for Wyoming except in with edema (“cow asthma,” vated by poor pasture growth, and composition may be drought years is a bacterial “grunts,” “fog fever”) is asso- forces animals to seek less tempting to ranchers when infection that most often af- ciated with an abrupt change palatable, potentially toxic quality feed is scarce. Unusual fects the brisket of horses. It from dry pastures to mead- plants. Plant populations in or unbalanced rations can lead is called pigeon fever because ows, especially regrowth pastures tend to change as to mineral and other dietary of the pigeon-breasted appear- meadows after haying. The drought-resistant weeds begin deficiencies leading to insidi- ance of affected horses. disease occurs because of high to dominate more desirable ous disease in herds. An ex- The disease is caused by concentrations of the amino forage plants. Drought stress ample of toxicosis due to an a specific bacterial agent and acid L-tryptophan in forage. may increase the toxicity of unusual feed involves whey, is probably spread by flies. It The amino acid is converted some plants such as nitrate- which when used as a supple- is not known how drought pre- to a toxin in the rumen, caus- accumulating and cyanide- ment may contain toxic quan- disposes horses to this non- ing an acute reaction in the forming species. Exposure to tities of salt (causing seizures) fatal disease. More than 100 lungs. The result is an acute toxic plants may occur directly or fat (causing bloat). Grazing horses with this disease were respiratory distress syndrome on the pasture or in poor qual- of turnips has led to This is the skinned head of a diagnosed in Wyoming in in a high proportion of the ity feeds obtained from fields polioencepha-lomalacia (PEM) cow with extensive abscess 2002, most in the months of formation in the cheeks, herd. Cattle display character- stressed by drought and/or from excessive sulfur. August to November. probably due to coarse feed. istic breathlessness, distress, overgrown with toxic weeds.
Page 8 Spring, 2003 UW College of AgricultureTrees and shrubs demand specialwatering to survive droughtDonna Cuin Trees and shrubs also tree roots. Remember, treesUW Cooperative Extension need to be watered periodi- evolved in forests where treeService, Program Associate I, cally during the winter canopies shaded their rootsNatrona County months. The necessity for day in and day out through- supplemental water depends out hot summer days.T rees and shrubs are the foundation plants in anylandscape whether in a rural upon the presence or lack of snow cover, daytime tempera- tures, and wind. Typically in Trees and shrubs have developed over time with de- caying organic matter cover-windbreak or an urban setting. Wyoming the recommenda- ing the soil over their roots.These plants live the longest tion is to apply water when the The use of organic mulchesand are the most expensive daily temperatures exceed 45 helps to recreate a more natu-assets in landscape plantings. degrees. Warm winter tem- ral environment. As organicWith long-lasting, severe peratures lead to the loss of matter begins to break down,drought conditions, trees and snow cover and are usually the presence of fungus willshrubs should receive the focus brought on by warm Chinook increase, further assisting inin sustainable landscapes. If winds. Watering is not recom- this break-down process. Treeswater supplies are short, trees near the tips of their growing application is to take the diam- mended during high winds. have lived surrounded by fun-and shrubs should receive the ends. However, the critical root eter of a tree times the five Summer or winter, trees will gus for centuries. This is whymost attention. mass is within the drip line of minutes needed to get 10 gal- need the same amount of it has become increasingly Tree roots develop in a the tree. By watering within lons of water flow. Therefore, water in the soil to sustain life. more prevalent forfashion similar to that of their the drip line, one can create 8-inch diameter trees will However, in the winter, water homeowners and landscapersabove-ground growth. Trees soil moisture for the greatest need 40 minutes of water flow will not need to be applied as to do away with turf grassesdevelop approximately 40 majority of the roots. to receive 80 gallons of water. frequently. Watering once a growing over tree roots withinpercent of their mass above Moisture applied to turf Most trees will need three month from October through the drip line of trees andground and 60 percent below grass associated with trees will waterings per month from April will supply plenty of wa-ground. This means that there also supply moisture to the April through October. ter to sustain trees. Shrubsis more living plant tissue be- tree roots below the roots of Shrubs need to be wa- may benefit from wateringlow ground dedicated to ab- the turf grass. If watering rows tered approximately once ev- twice per month if conditionssorbing moisture and gather- of trees in a windbreak, one ery week if there is a lack of warrant watering. Shrubs willing nutrients from the soil. should think of it as watering natural precipitation. Estab- also require less water in theHowever, the roots tend to the tree area, not the rows of lished shrubs need between 2 winter months than during thespread farther from the trunk tree trunks. Be sure to spread and 10 gallons per week based growing season. Establishedand do not grow to a depth water applications over the upon their size. Small shrubs shrubs will only require 5 togreater than 18 to 24 inches. entire tree-root areas, rather less than 3 feet tall need 2 to 18 gallons per month duringThis translates to a shallow than focusing on areas close 4 gallons of water per week. the winter months. Newly es-root structure growing close to to each tree trunk. Medium shrubs between 3 tablished trees and shrubsthe soil surface and spreading Water deeply and infre- and 6 feet tall need 5 to 7 gal- may need watering twice peroutwards from the trunk. This quently to create moist soil to lons. Large shrubs more than month depending upon win-spread can be up to three to a depth of 12 inches. To as- 6 feet tall will need from 8 to ter conditions.five times the height of a tree. sure survival, a tree will need 10 gallons per week during the Mulch is a garden product Watering trees at the drip 10 gallons of water per inch growing season. that is almost crucial for suc-line of tree branches and be- of trunk diameter with each Newly planted trees and cess in growing trees andyond is recommended. As watering. A typical garden shrubs need additional, shrubs during drought condi-shown in the above illustra- hose on medium pressure will supplemental water applica- tions. Mulch is typically some-tion, the finer moisture-gath- supply 10 gallons in 5 minutes tions during their first growing thing organic like shredded shrubs. Grasses tend to haveering root tissues are at the ex- of run time. Test hoses for ac- season. These plants need to tree bark, chipped tree branch root structures more suited totreme ends of the tree roots. curacy. The way to calculate expend a great amount of en- material, coconut hulls, or bacterial colonization ratherIn order to gather water, the how long to leave water run- ergy to develop a healthy nu- pine branches and needles. than the fungal colonies whichroots need access to water ning for appropriate water trient and water-seeking root There is an extensive list of are preferred by trees. system in their first year. This other materials that can also Mulched areas will also help growth requires water and make wonderful mulch for improve the pH acid level of nutrients from the soil. Due to tree areas. In Wyoming these soil around tree roots. the dry climate in Wyoming, products can be difficult to use These practices in rural the water source must be in high-wind-exposure areas, and urban landscape settings supplemented even in low- but rocks and gravel can pro- will improve success with trees water-requiring plants until vide alternative sources of soil and shrubs and help to con- the root system is developed protection. The main purpose serve water during years of and well established. During for using mulch is to prevent drought. For suggestions on that first critical year of root soil moisture evaporation. The species and varieties of trees establishment, small shrubs organic mulches will also and shrubs suited to a particu- will require 4 to 6 gallons of break down to add nutrients lar area, contact a local Uni- water per week. Remember to to the soil and improve its versity of Wyoming Coopera- keep in mind that the soil moisture-holding capacity. tive Extension Service office. should be kept moist, not wet, Mulches will help in weed pre- to encourage healthy root vention and in keeping soil growth. temperatures lower around
UW College of Agriculture Spring, 2003 Page 9Rigidula medic is a new annual legume forage crop being developed by UW at the Torrington Research and Extension Center for grazing in dryland cropping systems.Equal in quality to alfalfa, the new crop (shown here on April 15) will regenerate from soil seed if given adequate fall moisture or will maintain viability for another year.Alternative crops can helpduring drought emergenciesJim Krall age or that lack a market struc- consideration that could lead pastures with such crops as tions on the production of al-Professor, UW Department of ture. Type III: Crops that are to additional narrowing of the forage turnips. ternative emergency forages.Plant Sciences lacking both a market and a choices is the potential effect To get the best out of win- These can be found at the Web production package but which of herbicide carryover from a ter wheat, it takes 1.8 pounds site www.uwyo.edu/CES/D rought is on everyone’s mind. Regardless ofwhether it is for irrigated crops have potential for both. Among the first type are stand- bys such oats, barley, and previous crop. Do not under estimate this, especially dur- ing dry periods. and 1 pound of nitrogen and phosphorus, respectively, to produce a bushel of grain. plantsci.htm. For summer annual crop- ping, corn, although not anor dryland agriculture, the spring wheat. In the Type II What is the weather going Consider split applications alternative crop in the region,search is on to find an alterna- category would be crops like to do? Many producers have between fall and spring and an is an example of a crop thattive crop or practice that will safflower, Niger thistle, canary planted irrigated winter application of 15 to 30 pounds offers some alternative prac-help get the most out of low- grass, flax, and amaranth. wheat. The crop has a lower of nitrogen at flowering to tices for short-water years.water conditions. In effect, an Type III crops would be milk- water use, but the peak water boost grain protein if there will Consider lower populations,alternative on crop dryland is weed, canola, and hemp. use is early (April 15 to July be a premium for protein. reduced fertility, or short-sea-anything other than winter Grouping crops by season 5), which is important if there There are good pest manage- son hybrids, but remember itwheat. For irrigated areas, it is is another way of narrowing is a concern about late-season ment packages available for is important to get the cropanything other than corn, dry the choices. There are cool- irrigation water availability. this crop, but careful monitor- started right away with a shotbeans, sugar beets, and alfalfa. season grasses like winter Grain yield potential can run ing of insects, foliar diseases, of water if needed. Searching for more than wheat, spring wheat, oats, up to 120 bushels per acre and weeds is important. The Each new crop has its ownthese crops is critical because triticale, and barley and cool- under the best irrigated con- University of Nebraska offers set of production parametersnot all alternative crops have season broadleaf crops like ditions, and with average wa- an irrigated winter-wheat pro- and market challenges. Therea production package or a peas, canola, crambe, and len- ter 80 bushels per acre is rea- duction guide at its Web site may yet be a proso millet con-market to fit Wyoming. David tils for spring and early sum- sonable. One can still get a at www.ianr.unl.edu/pubs/ tract to be had, but producersBaltensperger of the Univer- mer production. There are crop of 60 bushels per acre fieldcrops/g1455.htm. Con- may end up looking to forages.sity of Nebraska Panhandle warm-season grasses such as under stressful irrigated con- cerning a second crop of bras- If so, check the University ofResearch Center breaks alter- corn, sorghum, sudangrass, ditions. With a normal year sicas or warm-season grass Wyoming Web site atnative crops into three catego- sorghum-sudangrass hybrids, and secured irrigation water, forage, there is less to go by, www.uwyo.edu/ces/Drought/ries. Type I: Crops which pro- proso, and forage millets and one can plant a second crop but this does not mean there Drought_Main.html as well asducers know how to grow, that a few warm season broadleaf of brassica forage pasture or is not information available. the University of Nebraska Webhave an established market, alternatives like some forage one of the warm-season grass University of Wyoming Profes- site at www.panhandle.unl.edu/but that may not fit current bassicas, sunflower, safflower, forage crops. In New Zealand sor Dave Koch of the Depart- drought/html/rural.html foreconomics. Type II: Crops that and chickpea for summer and producers plant a large num- ment of Plant Sciences has more information on droughtare short of a production pack- early fall production. A further ber of annual forage brassica produced extension publica- and drought strategies.