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<br />;lppcar in your lawll and you pay aucntion to Ihcir
<br />lHHnbcrs. Y{lU call gel all idea or the ~ize or the
<br />,!:n1h POPUblioll hl come. Porc\Varncd i~ fore-
<br />armed.
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<br />2. Evaluation of risk. Unlike lhe "see and spr;lY"
<br />;Ippro;tch, lPM c::t:lolishes action thresholds. For
<br />example, if Japanese Beetle grubs might be a
<br />problem in spring or fall, dig a onc foot square
<br />plot (2-3 inches dccp) :::md simply count the grubs.
<br />lrmorc lhan 6-8 grubs per square foot arc prcst'nt,
<br />L'ontrol may be needed.
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<br />3. Physical! cultural controls. For example, adult
<br />hpancse Beetles can easily be h::mdpickcd and
<br />destroyed.
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<br />4. Biological controls. Encourage predators and
<br />parasites to take up residence. For example, car-
<br />dinals eat Japanese beelles. If birds are attracted
<br />with a nesting si{e, water, and winter food, they
<br />will be ready for duty when the beetles come.
<br />Beneticial nematodes can be introduced to attJck
<br />[he grubs_
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<br />How carl pest damage be prevented?
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<br />MOS11awn diseases are caused by fungi, and they
<br />are most likely to occur under particular conditions of
<br />temperarure and humidity. Thus. an important part of
<br />prevention is learning which diseases tend to occur
<br />during which seasons_ Selecting resistant grasses, wa~
<br />termanagement, fertility management, mowingl thatch
<br />management, and aeration are all important in disease
<br />prevention. For example, dull mower blades tend to
<br />tear the grass, and the resultant ragged cut allows
<br />disease organisms easy entry. Having a mixture of
<br />lawn grasses also increases disease resistance,
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<br />One method of both prevenling and treating lawn
<br />diseases is to increase the numbers of beneficial soil
<br />microbes. These microbes, which Qut-compete the
<br />disease organisms, are found in aged cornpostpiles and
<br />com posted tree bark. They are also available in some
<br />commercial organic fertilizer products. Least toxic
<br />chemical treatments include plant-derived products
<br />like ncem oil or garlic oil as well as fungicidal soaps.
<br />For a thorough discussion of integrated pest manage-
<br />ment for lawn diseases and pests, consult a reference
<br />such as Olkowski. Daar, and Olkowski (1991),
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<br />St~}.8:'~S ~'~~~~~~~~R~~!?mi~~S~~7~lf~~;?}~.:,j-~r~j~~~}{
<br />:' Practlci!,\farer1c6iisffITiii'~niif{dS'8":i'rt' :;'te~l1~':
<br />.' ,..".:".-..,.:.."',.,-.A}..,.........'.,.:.J}'... .g:'.,.,/'l.{',.-<....,p.~_:_,.~.t..--:.".,.J''''t
<br />niques., For albw iripinla.,,:ni..vat~r infre'li1i:hlly;in.tIie:~
<br />earl y ,roOming; iiufiS'oalC;1h~'I~V{ nMeif:iPor)lli loWer);
<br />in pulla;vn!w"rlir'?njy}h~rr\h~li~H::de:fi.ijl'\~1f':io/~i
<br />i l. and~al ibrat,esp.rl oJ{] eisii;(!i,iJi"to/i:eHlii'p~~~Wii~:';
<br />acee 'filial' lfie~' .'1ffi'tP\'a:~'.~;btgtet;l1"""'1~'itrlif~~
<br />p; ,... ,gr .. .,. Y...q . ;.' ". .Y<i,.u;"~""r,,i'.~
<br />.:,: .: ..;r.'c~/; ,~;;ej.'l',::;[~:_ ;:< :;:;~.:~.":.t~;..::'\~..i::.L1~.tiJ:~:..'~j;}~,,Y1~
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<br />ErririL:nllawn irri~:llioll is nul well lInd~rslood hy
<br />most homeowners. Of[cn, Ihe lawn is ~i"cn a lig.ht
<br />walcring whenever the weather is dry. This appro;\C;h
<br />may do marc harm lb:m good. .since the water never
<br />penetrates ol;low the top few inl:hes or soil. Such
<br />shallow frequent watering leOlJs to shallow rooled.
<br />fragile gr<lss. II is much better to water less often hut
<br />morc deeply_ Also, wl1tcring in the early morning
<br />avoids wasting water Ihrough evaporation.
<br />
<br />At the other extreme, SOllle homeowners inst,lil an
<br />nutomalic system nnd water whether {he lawn needs it
<br />or not.lllis ovcrwatering lends tocxccssive (OP growth,
<br />weakens the grass, requires frequent
<br />mowing. and sets the stage for dis-
<br />ease ta flourish. Overwatering alsa
<br />can leach away nitrogen even with.
<br />out overfertilization (see Technical
<br />Nole 56), Inslead, the goal should be
<br />to water only when the lawn really
<br />needs it.lffoatprints can be seen after
<br />walking across the lawn, it may be a signal to water.
<br />Sprinklers should be carefully calibrated in inches of
<br />water per hour to determine the time required to wet the
<br />soil to a depth of six inches. In times of drought, it is
<br />necessary to make up the difference using a general
<br />rule of thumb of one inch of water every 7 to 10 days
<br />(or water until it reaches a desired soil depth of 6-]8
<br />inches). Be sure not to apply water faster than the
<br />ground can absorb it, or runoff may be crealed. Lastly,
<br />water harvesting techniques such as sloping walkways
<br />toward turf areas or extending downspouts into the
<br />ground can be used to promote runon and make more
<br />'efficient use of rainfall.
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<br />Finally. it should be kept in mind that it is not
<br />natural for lawns to stay green year-round in most parts
<br />of the country. Since grass grows from the crown
<br />instead of the tip. the planllets (he leaves go dormanl
<br />in order to survive a droughL Though brown..crunchy,
<br />and to an appearances dead,lhe lawn will revive when
<br />cooler temperatures and wetter weatherretufTI_ Drought
<br />should be regarded as a natural seasonal event. like
<br />trees losing leaves in the Fall. Homeowners lhat resist
<br />the urge to water save on water bills and get a welcome
<br />break from mowing chores.
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<br />;rn:N\l::i:\ill.l~..:um\!!)~~E;Tl~T"';''''~..1EI.ID
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<br />Sensible irrigation rates can
<br />reduce the potential that nitrate
<br />flushes through the soil and
<br />into the groundwater.
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<br />~~\ol..llii\,~\,~.,..\l,.~;:';7:\1r\t""'::..'I:JX;J
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<br />Helping communities move toward {he low input lawn
<br />
<br />The accompanying Lawn Care Field Guide gives
<br />exnmpJes of publications intended to help homeowners
<br />move toward the low input lawn within their region of
<br />the country. The field guide is divided into the six
<br />major grass zones of lhe United Stales. Mi.loy of the
<br />publications included in the guide Iwvc used a variety
<br />of wchniques to educale thl.: public; ahout low inrut
<br />lawn C<lre including: voluntcerOulre~lch progri.lms such
<br />as master g<lrdencrs. newsletters or bill inserts, :mu
<br />demonstration g.lrdcns. An approjJch thaI is bcginnlllg
<br />
<br />Watershell Protection Techniques _ Vol. 2, No.1_ fall1S95
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