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Show ( By J . . r . Parrisli Parrish , County Agent ) ) l\lcth l lcth \ Methods ds of Destroying Destroymg AtraUa Alfalfa Alfalfa\\ccvil Alfalfa ccvil 11 \ \ \ eeVil eeVilPauuers . Paimcrs Pauuers Faimers are urged eeVilI to make m9ke mike a c'cse ccse dose c'cseinvestxgation doseinvestigation c ' cseinvestigation I investxgation investigation of all alfalfa fields to toobserve toobsenc observe ( ) bcen ; e the numbers of newly newlyJla.tched newlyhatched newlyliatched toI I Jla.tched Jlatched hatched . wee11 weevil wce wee\ wee \ il 11 larvae 'worm worm ' ' worm . The Thecoler Thecolor Thecolor coler color of the lirvae hrvae larvae is a greenishyellow greenish greenishyeUow greenishyellow yeUow yellow : with a small black greenishI head headfull head'Then headWhen I 'Then Then ' ' full grown , the larvae are areabout areabout areabout about - % 'I I ' . , c of ! an Inch long and are arelght arelight arelight lght light ] gicen gxeen gieen in color Shortly after afterhatching I ) Il1atching l1atching hatching in the hollow portion of ofthe ofthe ofthe the alfalfa stem , , the young larvae larvaeera larvaecrawl larvaecrawl -era era crawl - \ 1 up to the bud of the alf.a alfa alfalfa alfalfastock alfalfastock . lCa lCactoc ctoc\ ctoc stock ctocwhere : ; \ . where feeding takes tal.es tales . place It Itis Itis Itis is at tills this stage where wl1cre the greater greaterportion greaterportion greaterportion portion of the damage is dene dcne done by I I I I the alfalfa alfatra weevilThere weevilThere weevil weevilThere There is but one generation oC oC"eevil o oweevil oweevil "eevil eevil weevil " in m a year but they bald baldfrom ha hatclfrom te from the eggs at varied time times thne timesthroughout thnethroughout ; throughout the growth of the .first first .firstcutting 1irs . . + ' cutting of alfalfa The rate of hat- hat hatching hat hatching - ching thing depends en on , weather \ eather condi condi- conditions conditions conditions - - tions They usually hatch raptdly rapidly raptdlyIn rapidlyin rapidiiin In warmeatller warm \ weather \\eatller eatller \ and slowly when whenthe whenthe wherthe the weather is cool and cloudyAIC.JlIa cloudyAlf.ilfa cloudy cloudyAlfjifa Alfjifa AIC.JlIa AICJlIa Alf.ilfa Alfilfa . . \ weevil ecvIl ma may ' be t'ontroUed tontroUed controlled t'ontroUedby controlledby ' controlledby by individual farmers fgrmers fsrmers in 111 their own ownalfalfa ownalfalfa ownalfalfa alfalfa fields regardless rcgardless of a heavy heavyinfestation heavyinfestation heavyinfestation infestation on surrounding sUlTounding farms farmsThts farmsThis farmsThis Thts This is because the spread of alfalfa aUaUa alfalfaweevil ' \ weevil ecvil is slow and gradualCle gradualClean gradual gradualClean Cle Clean m , . well wen cultivated cu1t1\ated cu1t1 ated \ farms afford af- af afford af afford - - ford less favorable tfa\orable tfa orable ( \ conditions 'COnditIons renditions ' for forthe forthe forthe the winter hibernation of oC the adult adultweevIl adultweevil adultweevil weevIl than a poorlv poorly cultivated cultivatedand cultivatedand cultivatedand and neglected ' ilfalfa 11falfa 'ilfaifa ilfaifa flield fiield meld Stands Standscf Standsof Standscf cf of old , thin thm alfalfa proVIdecevII provide weeviIwith \ - weevil \\-cevII cevII weeviI cevIIwith with almost ideal conditions Cor for Corthclr fortheig fortheir thclr theig reproduction wheieas whereas v . hel cas . . , young } voungthick Dung , thick vigorous growing growmg stands of ofalfaIra ofalfalfa ofalfalfa much1Jess alfaIra alfalfa . afford these insects msects a much1 much muchless , Jess less fa\oJAble fa oJAble favorable favorable \ environment enurcmnenf for for'theirincreasCy fortheirincreasCy ' 'their their 'theirincrease Theirincrease ' increase . . This Tlus ThS { difference dlfference ] is S due to toth tothahig toth'e tothe thahig th ' ' .higher higher . , tier temperature prevaihng prevailing prevailingin prevaihngin toI I . in fields fielaS ' " " with thin thm stands stande ; than m in mI mthose inthose inthose I those "having having nE1\mg nE1 mg 1savrng " . \ heavy hcavy stands stand stan ; - ; * ' Investigations Imestrgatlons have dcmcnstrated demonstrated dcmcnstratedthat demonstratedthat demonstratedthat that by Qy cutting cuttmg the first crop of alfalfa al- al alfalfa al alfalfa - falfa about the time it begins beginc ; to tobloom tobloom tobloom bloom that most of thecung the \ vcung \cung cung young un- un unpala un unparasitized un-paiasitized un paiasitized - parasitized pala It1zed lanaeorms larvae lanae "worms worms " \\orms orms \ , . , and andmany andmany andmanv many unhatchedeeVlL unhatched weevil \\-eeVlL eeVlL \ - eggs shU still stillnt stillin 111 nt the alfalfa stoe3re stock stoe\ stoe \ . are 3re destroJed destroyed destroJedstarvaticn destroyedStarvation destroyedStarvation starvaticn Starvation and the sudden increas mcreas- mcreas mcreass.d increase4 increased - s.d sd e4 ed . tempeiature tempelature temperature cf of the ground le- le ze- ze zerzlting let'i11tmg ic-ftultmg ic ftultmg - ; t'i\11tmg t'i ti 11tmg rzlting ' ; \ } from fronl . . the removal remo\al remo al \ of thericp the theC'ICP thencp C'ICP CICP ricp ' kills kJlls most of thevec tlie the \vec\ vec \ weevil vecII \ II lanae larvae lanaend larvaerid laivaernd -nd nd : - rid the voung oung young pupaeTn pupaeJn pupae pupaepi pi Tn Jn most cases in 111 this dlstnct district dlstnct"here districtnhere district"ft districtft "here here nhere " " here fields have ha\e ha e \ fiom flom from a light to toheay toheavv , heay heavy } v . weevil e\1l e 1l \ damage , . it is 1'3 13 ' suggested suggest suggest- suggestf'd suggested " - ' ed f'd fd that the U1e a alfalfa Ifalfa faifa be cut eailv enlj early : , ' and andI and'that andthat andthat I 'that that ' fOl1JOed the f111\\ f111 f111m f following llcwurg : \ m treatment be fOl-1 fOl 1 fol- fol followed fol followed - lowed JO\\ed JO ed \ \ , , The alfalfa is cut and ra- ra re- re removed ra1nO re removed - moved 1nOed 1nO\ 1nO \ ed from the field as quickly as aspossible aspossible possible ] ) CK'3ible CK3ible ' " while "hUe hUe the gI giound ground ound is dry As Asscon Asscon Assoon scon soon as the hav haj hay is off the ground groundthe groundthe groundthe the alf'1'fa alf1fa a1f1'fa a1f1fa alfarfa ' ' is scringtoothed sormgtoothed scrrngtoothed ; thor- thor thorcuhl thorcughly thor-cu thor cu - cughly cuhl ! : ; hlv } . , , followed fcl1ov.ed fcl1oved fclloued . by dragging draggmg 'with with 'witha " ' witha th thn n a spike sptke toothed hal hairow harrow ro\\ ro roand \ and v . with Ith a aspecially aspecially Ifjthe specially piepired plep'1red plep1red prepared ' brush drag If Iftne Ifj Iftne tne the " spike "pIl.e pIl.e pIle . toothed teothed hairow harrow hauo ' . is ) ] s 5 used usedIre useda a : \ wire \\Ire Ire \ or cr bat baibed batted bed bedure \ wire \ure ure entanglement entanglemententangled entanglemententangled ) entangled undeineath undetneath underneath the harrow harrowhas harrowhas harrowhas has plovedeD pioved ploved proved \eD eD very \ verv satisfactory satisfactor } m in mcreatmg increating increating creatmg creating a vigorous v1gol"cus v1golcus : " dust By thIS thISmeans thismeans thismeans means practically practicall 100 pel pet cent kIU kill killof killof of ( ) f the ' \ weevil ceVlI Ian larvae ae will resultA resultA result resultA A second method has pro proven en sue-I sue I sueIcessful suc- suc successful suc successful - - cessful by effectively destroying destro"mg destromg } " by bydustmg bydusting bydusting dustmg dusting or spiaymg splaymg spraying with Calcium CalciumOnenate CalciumOrsenate CalciumOrsenate Onenate Orsenate ; at the rate of 2 pounds peunds per peracre peracre peracre acre It it is desired to apply it m in mthe inthe inthe the form of a spiay splay spray , . , the Calcium CalciumOrsenate CalciumOrsenate rsenate Orsenate ' ) I is placed rlaced in 111 a < ; spiay play spray tank tankIt tankit It the iate late rate of cf 2 pounds jounds Founds : to 100 galians gal- gal galI galns gal-(3ns gal (3ns 3ns - ians I ( ) ns ofater of cf \ water \\ater ater \ Tins TIus This spiav splav is applied appliedt t the rate of 100 gallons to eachcre eachcre each cre ! 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