CIS 1160

University of Idaho • College of Agricultural and Life Sciences

Procedures for PlantingDryland Grasses for Small AcreageLandowners in Southeastern Idaho

by Brian McLain, Wayne Jones, Howard Neibling, Joseph Robins

Why this publication?Southeastern Idaho has seen alarge increase in populationgrowth, much of it with homesbuilt in rural areas. Recent popula-tion growth and drought conditionscontribute to critical water resourceissues in southeastern Idaho.

Legal constraints. Mostcurrent zoning laws require thesenew homes to be built on lots thatare a minimum of 1 to 5 acres.Protective covenants and statenoxious weed laws require thatthese small-acreage lots be main-tained properly. However, many ofthese lots do not have sufficientsurface water rights to maintainirrigated pastures or lawns: singleresidence culinary wells permitproviding water only for the homeand one-half acre.

Audience. Current and futuresmall-acreage owners in southeast-ern Idaho can use this publicationto help establish and maintainsmall acreages with reduced irriga-tion water inputs. With properlyestablished low-maintenancegrasses, fertilizer and pesticide usealso may be reduced.

Figure 1. A well-established grass stand with a variety of grasses isnot only better for grazing animals, but it also may reduce water, fertilizer, and pesticide needs. Photos by Brian McLain

Figure 2. Failed grass planting is full of invading annual and perennialweeds and volunteer alfalfa plants.

IntroductionPerennial grass stands that are established andmanaged properly will aid small-acreagelandowners by providing animal grazingoptions, soil erosion control, improvedaesthetics and overall environmental health,weed management and control, and increasedfire protection.

Establishing a perennial grass stand is along-term investment. Eliminating steps neces-sary to establish a successful grass seeding willlikely result in failure, or at the minimum, anunhealthy grass stand.

Expect to take several years to achieve ahealthy, viable grass stand. Uncontrollable vari-ables such as weather, moisture availability, andpest problems will often determine the success orfailure of a grass seeding.

When planning a low maintenance grassseeding, these basic principles must be consid-ered for success.

• Available moisture/irrigation and poweroptions

• Equipment availability

• Seedbed preparation

• Weed management/existing weeds

• Grass selection, seed quality, and seedavailability

• Soil types

• Seeding time

• Seeding method

• Seeding rate

• Seeding depth

• Grass maintenance during and after establishment

Moisture, the biggest limiting factorAvailable soil moisture is the biggest limitingfactor in planting grasses. The species selectedand when and how they are planted are highlydependent on water availability. In southeasternIdaho, most areas receive 8 to 14 inches ofannual precipitation. Some areas in Idaho, suchas the alpine mountain valleys, receive 16inches or more precipitation annually.

Precipitation. Determine the averageannual precipitation in your area by contactingthe Natural Resource Conservation Service. Ahelpful Web site that lists precipitation amountsby area ishttp://www.wcc.nrcs.usda.gov/climate/prism.html.

Irrigation water. Also, consider irrigationwater that may be available for the site to beplanted. Flood irrigation or sprinklers areoptions for irrigation. Flood irrigation requires asmaller investment in money but requires morelabor and larger water supply as compared tosprinklers. Sprinkler irrigation uses a limitedwater supply efficiently and distributes the watermore uniformly, especially on uneven ground.However, sprinkler systems require a larger invest-ment in equipment and power. If you plan topump water from a surface water source or a well,an adequate power supply must be considered.

Equipment: Buy, rent, or hire?Tilling, planting, and mowing equipment areneeded for establishing and maintaining a grassplanting. If equipment ownership is not prudent,then hiring custom operators or renting equip-ment may be options for small acreages. Localequipment dealers, rental businesses, soil conser-vation districts, and county weed departmentsare resources for rental equipment. Sometimeslocal farmers can be hired to do the equipmentwork, although patience is needed to workaround farmers’ busy seasonal schedules. Small-acreage farmers will more likely have appropri-ately sized equipment to accommodate the needof smaller- acreage plantings.

Seedbed preparation: Weed-freesoil must also be firm, fineSmall seeds, such as grass seeds, need adequateseed-to-soil contact. To accomplish the properseed-to-soil contact required for small-seededplants like grasses, the final seedbed should befirm, fine (no clods), moist, and weed free. Thismay require prior tillage and herbicide applica-tions. Tillage may include moldboard plowing,disking, chisel plowing, rototilling, harrowing, or rolling.

Weed control is necessary since weedscompete against the new grass seedlings. Weedsrob germinating seedlings of critical moisture,nutrients, and space. Weeds should be identified

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and weed-control plans implemented. Mostweeds fall within three categories—annuals,biennials, and perennials.

Annual weeds germinate from seed, grow,flower, produce seed, and die within one year.

Biennial weeds germinate from seed andgrow vegetatively the first year, then flower,produce seed, and die the second year. Annualand biennial weeds can be managed with tillageor herbicide applications.

Perennial plants live three or more years.Perennials can reproduce via seeds or plantparts. However, perennial weeds often requiremultiple tillage and herbicide applications. Allperennial weeds need to be controlled beforeplanting grasses.

UI Extension can help. Contact your localUniversity of Idaho Extension Office or countyweed department for weed identification andcontrol options. Find the office nearest you athttp://www.extension.uidaho.edu/find.asp. Youcan also find a number of guides to identifyingand getting rid of weeds athttp://info.ag.uidaho.edu:591/catalog/pests.html;click on “weeds.” Many of the publications canbe downloaded for free. Remember to read andcarefully follow the accompanying labels ifherbicides are used. See page 5 for more on weedcontrol.

Fallowing. In addition, it may be necessaryto fallow the site. Fallowing—the process ofusing tillage or herbicides or a combination ofboth processes to remove weeds and allow thesoil to accumulate moisture—is important if thesite has not been farmed recently and weeds—especially perennial weeds—have been allowedto establish. The soil may need to be fallowed forat least one year to stabilize the site prior toplanting a permanent grass seeding.

Plant a grain crop. It may be advantageousto plant annual grain crops for one or moreyears to stabilize the site prior to planting peren-nial grasses. If done properly, planting grainscan reduce soil erosion and aid in weed removalby using herbicides labeled for grains. The graincrops can be harvested as green forage or dryseed. They can also be mowed and/or tilledunder for added organic matter. Planting theperennial grass seed directly into the stubble ofthe final crop can be beneficial by providingprotection to the new seeding.

Recently farmed land. If the site has beenrecently farmed and is free from weeds, you maybe able to prepare the seedbed with only limitedtillage. While minimum or no soil disturbanceresults in retaining moisture and organic matter,herbicide applications may still be required toremove weeds and volunteer crop plants. In thiscase, minimum or no-till drills may be best forplanting depending on the firmness of the soilsurface. Planting directly into weed-free cropstubble can be an excellent option for establish-ing grass seedlings. The stubble will aid incapturing and saving moisture as well asprotecting young grass seedlings from damagingwinds and sun.

How firm, how fine? If the seedbed has beendisturbed by tillage, it is important that the soilis firm and fine prior to planting. Done mechan-ically with harrows, rollers, or seedbed makers,firm and fine soil assures good seed-to-soilcontact and proper seeding depth. Large clodsand excessive plant residue should be brokenup. A quick test for firmness is to walk across thesoil. If footprints are ¼- to ½-inch deep, then thefirmness is correct. If the footprints are morethan ½-inch deep, then more mechanical firm-ing is needed. Caution should be observed toensure that the soil is not either too powdery ortoo compacted as this will result in poor seedgermination and establishment.

Grass selection: See Tables 1 & 2Selection of the proper grass species is dependenton available water, including annual precipita-tion and irrigation water, if available. Otherconsiderations include land use, ease of estab-lishment, soil type, and seed availability. Table 1lists dryland grass species with varietiescommonly grown in southeastern Idaho.Detailed descriptions of each grass in Table 1can be found in the resources listed in the “ForMore Information” section of this publication.

Mix or monoculture? Choosing a mixture ofgrass species over monocultures will enhance thesuccess of the planting. Grass diversity providesincreased resistance to pests. However, mixedgrass stands will require careful managementwhen grazed due to animal preference of onespecies over another resulting in loss of less graz-ing tolerant grass species. Table 2 lists somerecommended grass mixtures and seeding ratesfor different precipitation ranges and soil types.

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The table gives grass recommendations based onthree general categories of soil types; good/deep,heavy/clay, and light/shallow/gravelly soils.Different grasses are better adapted for particu-lar soil types.

Seed quality—certified is best. Good seedquality will determine the seeding rate and vigorof the planting. Purchase seed that has a certified label. The label will state the species,variety, lot number, seed origin, germinationpercentage, pure seed percentage, amount ofinert material, and percentage of weed seeds.Certified seed is also required to be free ofnoxious weed seeds. Idaho’s noxious weeds areplants designated by the Idaho StateDepartment of Agriculture that spread rapidly,degrade land, and are very difficult to control.

Certified grass seed can be purchased at localfarm and ranch stores, feed stores, fertilizer deal-ers, and other seed dealers. A list of grass seeddealers is also listed on the Idaho CropImprovement Web site athttp://www.idahocrop.com/conditioners.aspx.Pre-mixed seed is available, or you can buy individual varieties and mix yourself, or plant amonoculture of a single variety.

Seeding rates are based upon Pure Live Seed(PLS) rates. Seed prices may also be based uponPure Live Seed.

Example: Pure Live Seed is calculated asfollows: PLS = percent purity X percent germina-tion. For example, if a 10 pounds PLS per acreseeding rate is required and the seed label states88% pure seed and 85% germination: 0.88 X0.85 = 0.75 PLS or 75% Pure Live Seed. Thendivide 10 pounds seed per acre by 0.75 PLS (10lbs/.75). This equals 13.3 pounds of bulk seedthat will need to be planted per acre to attainthe 10 pounds PLS per acre rate in this example.

Note that the higher amount takes intoaccount the extra contaminants present with thePLS. This calculation can also be used to deter-mine the best value when comparing prices ofdifferent lots of seed.

Seeding time: Moisture is criticalAvailable moisture is critical for seed germina-tion and grass establishment. Usually drylandplantings are done in the late fall or early winteras dormant seedings. Dormant seedings shouldbe late enough that cold temperatures delay

germination until early spring. For southeasternIdaho, this means that dormant seedings areusually done from late October throughDecember. The seeds germinate in early spring,and the seedlings have access to winter moistureand spring rains.

An optional time for planting is early spring.However, this is risky since much valuable mois-ture is lost before the soil is dry enough to getplanting equipment on the field. Supplementalirrigation, if available, may be necessary whenspring precipitation is insufficient.

Late summer or early fall plantings are NOTusually recommended for dryland plantingsbecause if seedlings are not well established theywill be killed by freezing temperatures. Latesummer and early fall plantings require suffi-cient time and moisture in order for seedlings toestablish and attain winter hardiness. Oftensummer and fall precipitation is not dependableenough for successful plant development.Regardless of planting time, it is imperative thatthe soil is prepared for planting well in advanceso that the field is ready when the window ofopportunity is open for planting.

Planting: Consider depth, seed-to-soil contact, even distributionBecause grass seeds are small, proper seedingdepth, good seed-to-soil contact, and even distribution of seed is critical for a successfulplanting.

Grass seed should not be planted any deeperthan ¼ to ½ inches. Double disk opener drillswork well if depth bands are used to ensure aproper seeding depth. The disks should befollowed with press wheels to firm the soilaround the seeds. If the drill is lacking presswheels, a chain or roller should follow to incor-porate the seed and firm the seed bed. If depthbands are not available, remove the seed tubesfrom the disk openers so the seed falls in front ofthe disk openers, thus allowing them to incorpo-rate the seed. Another planter option is theBrillion type, which drops the seed in front of anindented roller, which then incorporates the seedinto the soil. To ensure even seed flow, plantersshould have a grass seed bin with an agitator tokeep seed blended and prevent seed bridging ornot feeding through the planter evenly.

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Broadcasting is another seeding method;however, 30 to 50 percent more seed is requiredto compensate for seeds that fail to be placed atproper depths.

Ideally, the seed is split in half with each halfbroadcast over the field, repeated with twopasses perpendicular to each other to obtain aneven distribution. Broadcasting can be donewith an air fertilizer applicator, a spinner typehand or wheel driven fertilizer spreader, or it canbe carefully spread by hand. Following broad-cast, the seed must be incorporated into the soilwith a roller, chain, harrow, or seedbed makerwith the tines raised. It is important that theseed is properly covered and soil firmed toprovide good seed-to-soil contact without beingplaced deeper than ¼ to ½ inch.

Broadcasting is the preferred seeding methodin areas where planting equipment is limitedsuch as rocky areas, steep slopes, or in smallenclosed areas.

Setting equipment properly. Whatever theplanting method, it is critical that the equip-ment is set for the proper seeding rate, depth,and even distribution. First, follow equipmentmanufacturers’ instructions to calibrate seedingrate and set planting depth. Then do a test runin a small area to measure seeding rate anddepth. Adjust equipment as needed. Rememberthat a firm seed bed will help prevent seed frombeing planted too deep.

Maintenance: water, weeding,mowing, or grazingAll perennial grass plantings require propermaintenance during and after establishment.Irrigation (if available), weed management, andmowing or grazing are all part of the mainte-nance program.

Irrigation if available is beneficial, espe-cially during grass establishment. Irrigationbroadens the choices available when selectinggrass species. Even a limited amount of irriga-tion in the spring and early summer on newseeding or established grass will supplement anyprecipitation received.

Weed management is very important ingrass stands, especially during establishment.The best weed management tool is a thick andhealthy stand of grass. Weed control is criticalduring perennial grass establishment because

weeds compete against the young grassseedlings for space, water, nutrients, andsunlight. Weed infestations can result in thin orfailed perennial grass stands. Thin standsbecome future weed problems. As previouslymentioned, any weed management programshould start first with identifying the weeds,since different weeds respond differently to weedcontrol practices.

Proper mowing is an effective weed manage-ment tool for controlling certain annual weedsduring and after perennial grass establishment.It is important to mow annual weeds prior toseed set. However, the grasses should not bemowed any shorter than 4 to 6 inches to allowfor good recovery and root development.

Herbicides are available for weed manage-ment in grasses. Herbicide selection is based onthe stage of grass and weed growth, the weedspecies identified, timing, and the applicationmethod. Weed control is most effective when theweeds are actively growing and when the grassesand weeds are not under stress. Only use herbi-cides that are registered for use on the grassespresent to avoid permanent damage to thegrass stand.

Annual weeds are best controlled when theyare small, and biennial weeds are best controlledwhile in the rosette stage or first year of vegeta-tive growth. Since application timing for peren-nial weed control varies according to the speciesof weeds and types of herbicides, read the herbi-cide labels to determine the optimum time tocontrol the weed species present. When usingherbicides, always read and follow the labelcarefully. Contact the local University of IdahoExtension office or county weed department forhelp identifying and controlling weeds or to askquestions about herbicide use.

Mowing or grazing: Leave 4 to 6 inches.Established grass stands should be mowed orgrazed once or twice annually depending on thegrass growth. Properly managed mowing orgrazing prevents the build-up of dead plantmaterial that chokes out grass plants, reducesspring green-up, encourages rodent populations,and increases fire hazards.

Always leave 4 to 6 inches of stubble tosustain healthy plants and enable quicker recov-ery. Mowing or grazing too short results in weakplants and thinning stands. Leave 4 inches ofstubble in the fall to give the plant enough food

reserves to survive the winter and provide energyfor spring green-up.

Grazing: Wait a couple of years. Grassstands should not be grazed for one to two ormore years after planting to ensure that grassesare well established and will not be pulled outby livestock or damaged by trampling.Generally, when grass plants start to produceseed heads, they are established well enough forgrazing. Avoid heavy grazing when soil is wet oron newly established grass stands.

Fertilizers not recommended for drylandgrass stands. Applying fertilizer benefits thegrass only during unusually wet years and ifsupplemental irrigation water is used. Fertilizerapplications during normal to dry years willweaken a dryland grass stand and encourageweed growth.

Finally, routinely evaluate the grass stand todetermine maintenance needs. Reseed thin orbare areas as required. Change managementpractices as needed to obtain the desired healthystand. However, sometimes a grass seeding willfail, even with the best planting conditions, dueto uncontrollable environmental conditions. Ifthis occurs, reseeding will be necessary. Once thestand is established and properly maintained, itwill likely survive many years.

About the AuthorsBrian McLain is University of Idaho ExtensionEducator in Jefferson and Clark Counties; WayneJones, is UI Extension Educator in BonnevilleCounty; Howard Neibling is UI Extension irriga-tion specialist at the Twin Falls Research andExtension Center; Joseph Robins is a researchgeneticist at the USDA-ARS Forage and RangeResearch Laboratory, Logan, Utah.

For more information (all online)Hart, K., R. Brooks, and J. Church. 2008. Pasture

Principles for Smaller Acreages. BUL 849.Moscow, ID: University of Idaho Extension.Download it for free athttp://info.ag.uidaho.edu/pdf/BUL/BUL849.pdf

Jensen, K.B., W. H. Horton, R. Reed, and R.E.Whitesides. 2001. Intermountain PlantingGuide. AG510. Logan, UT: Utah StateUniversity Extension. Available athttp://extension.usu.edu/files/publications/publication/pub__7717229.pdf

Ogle, D., L. St. John, J. Cornwell, M. Stannard,and L. Holzworth. USDA Natural ResourcesConservation Service. 2008. Pasture andRange Seedings: Planning-Installation-Evaluation-Management. NRCS PlantMaterials Technical Note No. 10. Boise, ID,Bozeman, MT, Spokane, WA. ftp://ftp-fc.sc.egov.usda.gov/ID/programs/technotes/tn10_pasture.pdf

Ogle, D., L. St. John, M. Stannard, and L.Holzworth. USDA Natural ResourcesConservation Service. 2008. Grass, Grass-Like,Forb, Legume, and Woody Species for theIntermountain West. Plant Materials TechnicalNote No. 24. Boise, ID, Bozeman, MT,Spokane, WA. ftp://ftp-fc.sc.egov.usda.gov/ID/programs/technotes/tn24_seedspecies.pdf

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Common Name VarietiesNative (N) orIntroduced (I) Character

PrecipitationNeeds (inches)

Bluegrass, Big Sherman N Bunch 9 – 18

Brome, Meadow Regar, Fleet, Paddock I Bunch 15 – 20+

Brome, Mountain Bromar N Bunch 16 – 20+

Brome, Smooth Manchar, Lincoln I Sod 16 – 20+

Orchardgrass (Dryland) Paiute I Bunch 16 – 20

Orchardgrass Latar, Dawn, Potomic I Bunch 18 – 24

Wheatgrass, Bluebunch Goldar, Anatone N Bunch 10 – 20

Wheatgrass, Crested (various) Douglas I Bunch 13 – 15

Fairway I Bunch 10 – 18

Ephraim, RoadCrest I Sod 10 – 18

Nordan, Summit I Bunch 9 – 18

Hycrest, Hycrest II, CD-II I Bunch 9 – 16

Wheatgrass, Intermediate Rush, Reliant, Oahe, Amur,Tegmar

I Sod 12 – 18

Wheatgrass, NewHy NewHy I Sod 14 – 20

Wheatgrass, Siberian P-27, Vavilov I Bunch 7 – 16

Wheatgrass, Slender Primar, Revenue, Pryor, San Luis N Bunch 12 – 18

Wheatgrass, Snake River Secar N Bunch 8 – 12

Wheatgrass, Thickspike Bannock, Critana N Sod 8 – 18

Wheatgrass, Western Rosana, Rodan, Walsh N Sod 12 – 18

Wildrye, Russian Bozoisky-Select, Bozoisky II I Bunch 8 – 18

Table 1. Dryland grass species commonly planted in southeastern Idaho.

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Table 2. Suggested grass seeding rates are listed as pounds (lbs) of pure live seed (PLS) per acre.* The table is divided intoprecipitation ranges. Within each precipitation range, grass mix options are listed in columns under the letters. The numbersgive the seeding rates in pounds of PLS per acre for each grass in the mix. Find the total seeding mix rate at the bottom of eachcolumn within the precipitation range.

Example: If your annual precipitation is 12 to 18 inches per year and you have a heavy clay soil, you can choose between twomix options—either D or E. If mix option E is your choice, then on each acre you would plant 5 pounds crested wheatgrass, 5 pounds intermediate wheatgrass, and 4 pounds Russian wildrye for a total mix of 14 pounds seed per acre.

*Seeding rates are based on using a properly calibrated seed planter. If you broadcast seed, add 30 to 50 percent more seedper acre.

Source: Adapted from Jensen, K.B., W. H. Horton, R. Reed, and R.E. Whitesides. 2001. Intermountain Planting Guide. AG510. Utah StateUniversity Extension. Logan, UT.

Soils: Good/Deep Heavy/Clay Light/Shallow/Gravelly

AnnualPrecip.(inches) Grass A B C

Mix Options

D E F G H I

8 – 12 Crested Wheatgrass 3 4 4 4 7

Siberian Wheatgrass 2 2 2 2 3 7 12

Russian Wildrye 3 5 3 5

Thickspike Wheatgrass 5 2 3 7 5

Snake River Wheatgrass 7 2 2

Total lbs PLS/acre 12 12 11 12 11 12 12 12 7

12 – 18 Crested Wheatgrass 3 5 7

Siberian Wheatgrass 3 7

Intermediate Wheatfrass 5 6 5 5 7

Russian Wildrye 3 5 4 7

Western Wheatgrass 2 4

Bluebunch Wheatgrass 6 4 7

Thickspike Wheatgrass 6 4 7

Total lbs PLS/acre 14 14 14 14 14 14 14 14

18 – 25 Orchardgrass 4

Smooth Brome 6

Meadow Brome 7 6

Intermediate Wheatgrass 8 8

Big Bluegrass 3 4

Bluebunch wheatgrass 3

Mountain Brome 5 6

Slender Wheatgrass 3 3 4

Total lbs PLS/acre 14 14 14 14 14

LimitedIrrigation(Springand EarlySummer)

Intermediate Wheatgrass 7 8 7 7 7 14

Smooth Brome 7 7

Dryland Orchardgrass 6

NewHy 9 9

Total lbs PLS/acre 14 14 16 14 16 14

July 2009 © 2009 by University of Idaho

Issued in furtherance of cooperative extension work in agriculture and home economics, Acts of May 8 and June 30, 1914, in cooperation with theU.S. Department of Agriculture, Charlotte V. Eberlein, Director of University of Idaho Extension, University of Idaho, Moscow, Idaho 83844. TheUniversity of Idaho provides equal opportunity in education and employment on the basis of race, color, national origin, religion, sex, sexual orien-tation, age, disability, or status as a disabled veteran or Vietnam-era veteran, as required by state and federal laws