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<br />appear in y()ur lawn ilnd you P:IY attention 10 IhL'ir
<br />Illllnht'r.s, Ytltl can get an idea of the size of the
<br />~nd) pn[H1I:l1ioll 10 C01l1e. Porcwarned is fon.>
<br />armed.
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<br />2. Evahmlion of risk. Unlike the '\cc and !'pr:ly"
<br />:lpproach,IPM c$I~lbli.shcs action thresholds. For
<br />example., if JapJ.nt::se Beetle grubs might be n
<br />problem in spring or L:1I1, dig a one foot square
<br />plot (2.3 inches deep) and simply count the grubs.
<br />lfmorc than 6-8 grubs per square foot arc prescnl,
<br />control may be needed.
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<br />3. Physical/ cultun-.I controls. For example, adult
<br />Japanese Beetles can easily be handpicked and
<br />destroyed.
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<br />4. lliological controls. Encourage predators and
<br />parasites {Q take up residence. For example, car-
<br />dinals eat Japanese beetles. If birds are attracted
<br />with a nesting sile, water, and winter food, they
<br />will be ready for duty when the beetles come.
<br />Beneficial nemawdes can be introduced to attJck
<br />the gru,bs,
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<br />flow can pest damage be prevented?
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<br />Most lawn diseases are caused by fungi. and they
<br />are most likely to occur under particular conditions of
<br />temperature 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 />ter management, fertility management, mowing/thatch
<br />management, and aeration are all important in disease
<br />prevention. For example, dull mower blades tend to
<br />tear Ihe 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 preventing and treating lawn
<br />diseases is to increase the numbers of beneficial soil
<br />microbes. These microbes, which out-compete the
<br />disease organisms, are found in aged compost piles and
<br />composted tree bark. They are also available in some
<br />commercial organic fertilizer products. Least toxic
<br />chemical treatments include plant-derived products
<br />like neern oil or garlic oil as well as fungicidal soaps.
<br />For a thorough discussion of integrated rest manage-
<br />ment for lawn diseases and pests, consult a reference
<br />such as Olkowski, Daar, and Olkowski (199 I).
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<br />step8:se~slti!~11'h~~!~~~:t\{8f!!%~;;';':'Ji~'i~f;"t
<br />... Piacticfi..wate"';~ojc6iis~rvin'/,tHl'i1dSdl":iif;:;:'tecl1'':'~'
<br />. . .~ ,. . ....:. .,:-~."::;:,:".?tw''''''~'''H.:.~..~:-...-:~;,<:<,_-:g., '?h/'?"~'l'j~
<br />DIques. For a low mpu t Iaw~iwaler lnfrequentlYilntlle,~
<br />early m.om i ng; buF~o.u::;ihe' il{~n:;W~ifiFbrl 'flo'!t~j):
<br />input ia\Vii,waU;~;?~iY:~)i~iilh';1';~Fdi.fi~j\~)iij~~~;
<br />i I, and c?libra\C sp!JnlJeis i i;qr.:t1ie1o)f'e.iilnii~f!~Wnl',
<br />accep.ft}0(~h~_1if~~way.':~:q't~~:&:tqp~~~~iW~_g~~
<br />.;;' '.T' ", - \;~_;;..':;-,,: ~;;'; ,.;,. ,,'.~; ".,f ~"~i-t.;~t{~~iLj'~i~),'1~'1
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<br />Efll('i~nll:lwn irri~:llion is not well ulltkrslood hy
<br />most homeowners. Often, the lawn is given a lig.ht
<br />watLrin~ whenever the wcalhcr is dry. This ;,pproach
<br />Illay do marc harm than good, sinL'c the water never
<br />penetrates helow the top r~w inches of .soil. Such
<br />sballow rrequent watering Ic;lds (0 shalluw rooled.
<br />fragile grass. It is much better III watcr less Orlcn bul
<br />more deeply. Also, watering in the carly morning
<br />avoids w~sting watcr through evaporation.
<br />
<br />At tbe other cxtrcmc, :.;omc homcowncr:-o ins(~lll an
<br />automatic system and water whether the lawn needs it
<br />or not. This overw<ltering le3ds to excessive top growth,
<br />weakcns the grass. requires frequent
<br />mowing, and sets Ihe stage for dis-
<br />ease to flourish. Overwalcring also
<br />can leach away nitrogen even with-
<br />out overfertilization (see Technical
<br />Note 56). Instead, the goal should be
<br />10 water only when the lawn really
<br />needs it. Iffootprintscan beseen 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 [0 10 days
<br />(or water until it reaches a desired soil depth of 6.} S
<br />inches). Be sure not to apply water faster than the
<br />ground can absorb it, or nmoffmay be created. Lastly,
<br />waler harvesting techniques such as sloping walkways
<br />toward turf areas or extending downspouts inro the
<br />ground can be used to promote runon and make more
<br />'efficient use of rainfall.
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<br />.re.m'~::ZS:lTh~..1\'iiUQlI,~:2io1~'i:F.,..,r,"'~.l!.~
<br />
<br />Sensible irrigation rates can
<br />reduce the potential that nitrate
<br />nushes through the soil and
<br />into the groundwater.
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<br />.~/;3~"",~mmlW':>.~;:\T."\tr..":;.~1
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<br />Finally, it should be kept in mind that il 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 plant lets the leaves go dormant
<br />in order to survive a drought 1110ugh brown,crunchy,
<br />and ro all appearances dead, the lawn will revive when
<br />cooler temperatures and wetter weather return. Drought
<br />should be regarded as a natural seasonal event, like
<br />trees losing leaves in the Fall. Homeowners that resist
<br />the urge to water save on waler bills and gel a welcome
<br />break from mowing chores.
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<br />Helping communities move !Oward the low input lawn
<br />
<br />The accompanying Lawn Care Field Guide givcs
<br />examples of pub lie at ions intended to help homeowncr:->
<br />move toward the low inputlawll within their region of
<br />the country. The field guide is divided inlO the six
<br />major grass zones of the United Stales. Many of the
<br />publications included in the guide have used il y;uicty
<br />of techniques lO cduealc thl.: purdie about low input
<br />lawn care including: volunteer(Hitreaeh programs.such
<br />ilS master gardeners, new~.;]cltcr.s or bill insert:-;, and
<br />uClIlon:-;tr:Hion g~lrd~ns. An arproach th;ll i:-o beginning
<br />
<br />Walersl1ed Protection Techniques a Vol. 2. No.1. Fall 1995
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<br />263
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