The rice water-weevil and methods for its control (Lissorhoptrus simplex Say)


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The rice water-weevil and methods for its control (Lissorhoptrus simplex Say)
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Tucker, Elbert Stephen
Government Printing Office ( Washington )
Publication Date:

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aleph - 29684359
oclc - 27940883
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Table of Contents
    Front Cover
        Page i
        Page ii
    Economic importance
        Page 1
        Page 2
    Historical account and distribution and descriptions of stages
        Page 3
    Life history
        Page 4
        Page 5
        Page 6
        Page 7
        Page 8
        Page 9
        Page 10
        Page 11
    Natural enemies and methods of control
        Page 12
        Page 13
        Page 14
        Page 15
        Page 16
        Page 17
    Suggestions for protective treatment
        Page 18
        Page 19
        Page 20
    Back Cover
        Page 21
        Page 22
Full Text

L 0. HOWARD. EntomologiLst and Chici of Bureau.




]E2. S. l ( 1 u,

,*. w

i'i EAU 01' E\TOMO110LOY.

L 0. lowARD. Ent1 monoli/i! ild ('Chi icf f 1Bur'eau.
(C'. L M ARI ,ATT. l'lt 'n il1IO!lixst .(I(I 'I lnf ('hii fi ill A ib cl'c Of Clhi'f.
R1. S. (CLIFTON, E.rci tire cA isftianIt.
"V. F. TAS'I'TET. ('hi(f C'iCI'.

V. II. ('iIITi NI: N,1 in cfi'/f nO f I(if'tf A.). I IOI'PKINS, i charg/ffc Of forest i ,cc/ t il rc.sltiltioisi.
\. I). /I IUNTH., i/i C(Iur'/C f sollf tr l ffli crope inc F. AL. AVI:I!STILR, ill i l(m( l (Ic Of l crcil oti foretllc iiln ictinl'c. lil in,'s.
A. L. QU'AIXTAN(C, in c(harI< of ccidil onts fi all inso et il rc'liiy/tioi(s.
I;. 1. PIiiILLirS. illn hil'ic if ,f hIT( culture.
1 '. I1. 11O;rI:S, iln c1/ir!f' Of p crcnlIiiing spi'fd of imoths, f/i<'ll "'ir,'.
1{0.I.A P. C'RiNE, till (tll/ir,' w ,f ( dillorial woirlk.
3IAI:L ('COLCORlD. itn 111h1r 'if liblarfyP.


\W I). IIuN.'P.R, ill c/l/irf./

W. I). PIERCE, (;. I). SMIll, J. 1). MITCHIL i, IIH.ARY PlINXvS, I1. (COAD, R. W.
IoirL 1ANI1). (clfttl c( ill, ci /ll ull-Ioll lrIr ilc i i/lr xtl'lil/ Inx.
.' (C. I1-1iS11O'P, A. II. J.:-NXN s,. 1I1. P. Wool), W. V. Ki.NG, oigagcdi in h-k iwrnvcsti-
pall iofw,.
A. MORGA N. 4;. A. ItR".\ N ., S. E. CltM., 1). ('.. PI:.,'.[. cnllag'cd ia ltob(a )
in ,s'f / ito fc t il/ft l i/o x.
T. I l OWAY, E.E. R. 1 m' !HE I 1f1I E'. A. [cT(;i r(;o1., \V. A. Ti"tOMAS", (tl`f!ift in r'.'I i!/fat if/f .
J. L,. \VIPIPt. (cf/IifIi 01 i/ /i'r1 iI ifI ill i rc t ifItlio/S.
1R. A. (C'OO.f!Y, I ). LV. "ANX Di.N, A. F. F..NORAI, (C. C'. KlI( MHII,.A!R, <.Ol/lt boriatrs.

C C "LAn No. 152. I ' '

United States Department of Agriculture,
L. 0. IHOWARD), Etmntmli t ;ml Chief of Bureau.


lN 1(. S. II N,.

EC'ONMIC I Im i tilM.

The most serious in-eelt emcy of Ir.oVwiiie" rii, in tIW 4HliM> oue
States iW tlIW rice w aleV -\wee\ il I/( .L'AX" to, 1, "NO/.; 11 ,1, Say') (Ii-'. 1).
,W het in its larval s-taig'e. tVe ifm cl i- knolwn t,1 rip,, r'm\'r-- ;>s tlhe
i; ricm rool im i *_-''"t." Tne !yvm, fe11%, lali< va ram on h m.( o At l da[ ts. anid
the ;i(lil11 w 11vil-' c il'clI .-oln. li ri1 1li) fo lini,. oil rip I ci\v' -..
Owi "i 1to (the exI lcii-iv g o' l,'\I' 4f rice 1i 1 >.cl2ion1- of Lotiui,, Iianal,
lexas. a .mi, A win,..s wvithin rccul ymmar., llic wmyvil Ima- t'oiinl vtcr\
l\av'rnhitlhc co,, lithini- i ln OIn ric ficl,/ I' r il- null ildi,'alioi in lirmp tio -
thni 0, tinl' icfra-c oft tli a a ;tnw am aq il tn tile mudmil T't otf V ar,' in
\\'hici rice lhtns lu l girom\'li in ;nitly m.'crihIo 'IV lie vo'\'llil)lii-nll oif
(Ih finih'lit'im -g'rowviii a e, i- iin ll i ., l- Slil(- li iilt, u:1 all' rV-nil( parll'tiowlar' cvlilvrT of I gh'h in fk'-ta ion lv Ow li wt qli,'ll li'ice growilip:
lias co(n>, iimrilt doia !,ai' too liltcr*ops: on
accott of the inmwl-c' altack-.
Tiw a.1mo nt of 1oI?" thlll is omcc sion- n lbv (lie NliNAc i illicitt to
c-ti"i t+, as tldip r1ed tion or vhell liK< I Veei \'a iivi ri.l\' ,e konel d ill
(1111=l'er 1i |oomilitie-. sime, all nnli re ol l ct cd ai lik wiml a d il l'r-
e!lf t rlio o ."-oi lO- u1of a licll ;l'n e ;lj>1l ,* -USill,'r !lie mv e-l injl- 11 1 'q .
alltlh mm, tli le ilil- >elduili fail omi ri l A tli nr j[04,Ucr t' d lle ttt i
ii ilin () Ii ol' mlir exrtTo nt oIr ilJ:mi la-, "li 'lli e\ -k-o hini. lQnt all
--I'(,, il tliN, ',p lato lion 1AM it i- eini- ,ile l>le. (c;esiiel;!l >latn llei nt-c
of (li ., t'"iol .'.'e or l ,rodu ionb i tlinl e i i't hy n! "t\ i/ w' e at I;cIa -
itiO1Ia. AT m.. \\" lIW>Ojlaeed 11- h.-. a- le\\ aI 1 per I el1l l:ilt llir i at;ae
in -oitie W', d- at M!!leiirl., Ark.. hjive lJeqe -,vcr, em oit~li to ciil
do( wn tlhe vi d n-l ;i i 7.A' pI r vorl1.




i f ,



~ ~



^ *- --- -"-

~c. '~

-~ t/~'-"---- -
...1. -.


Fi;. I.- lThil ic<' \v Twxxvil (Li.,iieroplxt',i, Nh picil r i '.:" i 1, lice plant showing ijiiJiiri's;
?i, larvxal .scars on section of root: c, section of rootlet showing feeding sears: d.
:xii'tr lini : c, c, roots siver<'i It larva, : f, injilrtd loaf : f, enlarged seel ion of inju~ir'ed
I, x, Ilirva, 'ild viex'. fiich ciilnra'lIi, : J, nillhair d sol noent of larva, lateral viow ; 1,
dorsill sat ruct i 'i of lar\a. (lrigiinal l



1 /









TH i 1, : l)l 1,;\ II J \ I I 1L.

The It work \v tlh> utreau on I lw Iice water-v, e\ il \;e~ 1erWunW\ 1
in 1!9>10 v )Ir. {'% Cood wIi uI i.- II t h toI oI Ir e\It 1. 1.
V:n D i, I e. Tl', ]PI I II t w riter I,'L; w(ork (1n 1be probl' m 1 V \ 111 I .
lI YIis ,irc l Ia r ImI a I I v ,in 'I t c: 1ot 1 :t .Il\ Ir. I 1 )4 1 are i1 If*( pl)d, 1 t .I .
T he )Ijet ol' thi-. pap IIIr i to "Iv o : at' I I i :I I I I ;>:I l l IfIrtI ti Io I
It I ovW ;\'aila lh Izou I I I I IeasIes to Ii t, l I I I, i- cnn1lro l it I
order lhat rice +roer. m av l ake |)riqi ,r ,lt'oi'l> 111 liclil 11' 1I ie ] Ie(

A ricu lturII a I \|x)wriI 'I ( I SI taI tio `,t n I l'qI I -intt tI I 'I IIzI l 'rolf. \\I lI.
D odso., d1ireCto, I I II I I it IidiI ; Iou IIi tl:tl II> at t lII St:Itte lIZ'e
St1 ltio,0 ( rowdlt a pnc l 1a ,1,-v I Ill w i II It' -- I+ oI | th (le nii ll(( i-li, IoIIs I v
,conuii ilH ii. a prc), limiiin rvy iD^O~ i' :tli{atio oI' 11/' tric't x,\altcr-w<'t'\+il l~v
rr. \Vilniioii Ncwcll. }in I'.1!*'.. dlu-,t' u r;f ,'r l'iil arkiio,}\v -l +H'di'i 'it.

T hi w ,'ccv'il ',wi t ,riiioii dl\' Ih--'- ril~t'd i, 1")! ;>-- l '> i ,,on: /'//< ,,-/
1)v T llotia. S Itay. It i l) d t(li, h r -])>cj{ -(1 1 \v e vII \ cV,' V I\+'I Illt I
",'tiL'. iaincl of I+i>>(rl()|l>trl rus v I )r ].0 1. 1 .- I Coi te ill 1-76. \1 '-
Conrte and Ilort haII Ive stated tlial tit' l e\vetvil eo IIIIIIIi )lI v iI I I;tI its
swai+Ijy plce-, thro l o nt h i eet tlI (' tl lr t ) f Io i, l' 'le ittld l tett's.
Its northelrn rI'Z I ex(tetd- i-nt1to I li ILowel. I'eoiiim n lia olf M itl iiir n,
;aeeord'(itn" to IIiltl );lrd l and t ;.lhvarz. atill( Dltl. v re, + +lcorded tllhe W-
cles as lhei;,.- takenl near ('11ciiillati. ()hlo. It i- also e|)orled froil
New Jersey. Mlarylan ]d. andt the I)i-trie't oI ('Colinl~ii:. MIr. V..\.
Schiwarz lh;-s .(,n) l 'I h "" th( l t -lie t'enh v llS li u'~>( ,rlwo trtit ccliti' all A oll)"
the Atlantio coa, (1inclilding.." the (mtill+ of Mexico), r'{ eeurP athn^ lIe
(;reoil tnd i s, c -i *tal v I'nilld in1lan1 d."
As ;il ilnjllui. lriou-s inll-, t.l the ales i 't tlle nttlentionll o'
rice fanners< ahnr the SaIvmllan iver in. M(ieor-;.1i anld S,onlh(: Caro-
lina. fI l st1 Dr. IL. (). ovwar, Id vi-iteI a ritce p ml; t 1t 1oio kno10\wnl A;
"Pr,{octor side of' the river., a lior tance Ixlow Sa, ant al]. {(i.. for+ tllie pilr-
pose ol sttd in ie iofeths lll ln e tili) tiet {c( o All ;a lcoult ol' li+-
o]-lervationlrs, incltdlili, notel on tle ricet walte +-wee\v 11. \\-;I- l)ildli-1ed
ill tle report or (le C nild Sttatel< 1iii>ls[111 111' A lri'icultll.. fIor
1P Sl atld ISS'2. B ilt little adv:an1ce ;>:1- lwenl nmiah in fI'irtller knlowl-
{ed1g{'e of rice-crop i hsects up) to tlhe prter'-el it s(-tiial ]ionl.

7 "1,' ,in, Ill.-- 1lhe l 1:1tt rc il-ect I- :I -m atll. l \Fl+-w"'rt,> ,'",ce\il (tii1'.
I. T1). Th ect li],c'Il dr1,ti ,l .o v 1+2 F. +A. S'ciwarzIl i (lle, accol t
above melitione'd is wrc (qluotcd:
l.(is'.s'<7o/ri. .vim piilrx,.. IAi;ii;ii : .\ e l'i iill fromn ] ii cf thl'nr x ;fi I lof
( il.i .,'i_'+t~xaI+ ,+oil. ove 'eid lw i th e dili' t -c lioreil .. .;ihlrs. 10111 /slllttly t~ll irel{1v oll-


veloped in ;i a raillalceolls (oaitih. which renders scales and sculpture irrecog-
lnizabhle. Jo'struml sli oul, ias In as head aIlI thoraix, stbcylindrical, densely
rul1osely pullulate, nleither stll(-ate nor (al'rinato: head densely punctnlate.
Tlniax as I l Io ; .;as wide. constricted lliteriorly. lateral 1w)es well developIed.
sides mderateloy rounded. base truncat:e, aI finely impressed Ielldiali eill. sur-
flace densely riloS'ely pun'lalte, sides t iddl wit alll wiw a IIA transverse il-
prlessionll. lytvra mlih widler ait base th:a tlh(Iorax and abollut twice as loll:
hliiiierii ilobil(ue, stnillly declivoills at apex, Iplitcatae-striiate, ilnterstlices wide.
Snlb(ollvex, "11 and :tllh more Iprominent :all declivity than tlhe rest. IProsternuim
flattelled, tlralnsvesel'8y inllpressed inll front o(f coxwe; alldomellnt coarselly pu1ll(1ate.
Til)i;e sonmewhat c(urvod, alrImell within a siron'ui terminal hook; tairsi ilarrow,
third joint not ollirlilnmte; claiws slender, apptroxilate.
Veryv little difference exi-ts between the sexes. The females usually
have a slightly larger body than the uales, and are often more dis-
tinctlv ma rked within a black area onii the back. The marks of colora-
tion, however, ,show more plailnly on live moistened specimens in the
field tlhanii on dry examples either alive or dead. According to Mr.
W. I). Pierce. a secondary sexual character is presented ,y the con-
figuration of thle scrolbe on the beak. lie has determined that the
scrobe of the female is siilihtlv curved, but in thle male it is practi-
cally straight. These fihe distinctions are 1lli. ult to make out with
certainty on accounjit of thle natural curvature of the beak.
The puptl.-No example of the pupa fit for description has vet been
obtained, as it is very soft aid atiy slight pressure or touch that is ex-
erted ill attempting" to remove one from th ie mud crusnhes or distorts it.
T/e. ('!/y.-All attempts to secure deposited (,__ have afforded only
partial results. For purposes of de-cription dependenlice must at
present Ile placed uponll the appearance (of egg obtained by dssection
of gravid female weevils. Mr. Wilmon Newell. in presenting a de-
scription ba:ed utiponi such observations, has stated that the e.', is
pure white, cylindrical anld ighlitly curved in form, anid has a length
about five times the diameter. It is barely visible to the linked eve.

1, 11FE I ISTOIi 'Y.


WXater is an element in \lhich the weevil delights. It swims readily
on or belleath thlie surface, ald it feeds, rests, anid mates almost as fre-
quentitly i ll tie water as above it. To (leterminle how long the adults
cai liive lunilder xxater', Mcr. C. E. HIood conducted a tes in which one
weevic l Ilied i after passingl' the first 24 fI I'ours of sl)billersioll, but two
(lid lnot die until after beli',' kept submeieged for fully 9(C hours. Tlhe
weevil ,doe11s noil (arry a blilbble of air for breathing purposes when it
x.. l)ow thle stirface, although tiivny globules (of air are apt to adhere
to parts of the bodyv. Without xwaer, the insect can not breed. The
eo- are l)rlprobab)ly depositd onl roots under water or i ni mud, and the

14)rva, a1nI] d snhtl- Olko the >11i1n,. req<4ireV a 1041 Olf ;l 4minll4 l;rth! i 1
whimh to live. wet o mpi wo- or w'ol whnt1 om able. voep'c at bd I appeyor
lo In, nect arY JIM for t IVn'd eve ql t oi ;Or ill the -la: -.
IO4 1 l A 1 I AN .

T1i' >euimllip lia c lilfe or hf li is etr1 de4mand thiait itV lprop r A',od
plaInts I'" adaptedl Or ri' ming" in t i .A I I14 l:iti+toi" or env irelv inI
waler. The adull wCev l il'elf is wol Wpi-locd to food On any [i>dlnt
unless lhe root, are atl lca-I parm itlillv covered with water or > l'tor il ].
In Smahl C'arolina 1D1% lloward (oh-tqrxe \wevil- W'cdng: IM SO ai-
taria. Scirlin..(' Q j trim. Nynpl)lima. and 'Nu[)!ar plant-" clani- n',o ip llv
known a '14' IaIrr Io'd. '/''.I 1. I i l wa r I Y. ;>iid -]):I t 11 1r-dOCI.
I1l'1i 'A 14 "1% li' rel: l w"'i l rN'i (/ "q/<:ii i r a s \ l : i"as
cultivait d j l/ i ,i;', (")n" m1pc<'ilt. i i;im- nl l r i r onllc l as :a
visitor oIn l i.NiA at \Victori;i. TA x. .Al I)o>ili"W c i r, my krtl- atdi -
tional oo Plants IV'(d' i)r ellyii tl\ o l,,i i-u- awl dliwv arv lliv rt'toill o ts ( 'rvat ions lthal \ 4v4'r1 ni('tl\v i d in :1,imi''na'. Iir. !II Id 1hi's r4 -
Port'1ed s el' oi" tiS11' I 1)ielii1in \:l 'l't .> l tl v'Ihe co 1 4ilp ll 1i1n anic of !>lil
gross .. and ti cr.''1' w\+ol." \lclch ^,*c a1 ('"hv. "a llI i'rrali
41*s>-'" \w'as I e'o1'C rded lhv Ni' 1 ). 1,. Van ill' i atl4 M ]iala'ol''a. T'I'cx.
Adulllt we \vils fed on t(in leave- id,' llie-e I)llndeteVrmllinelid girai -(-e- and lIlh
1larvw w 'e i o nd oli itho \, rot4 the, writer tas n Pa:11 hil'ln n i4 \am 1 hl'a to 4a lto, l Q lrWIdiledI into
the (or tlir 'V. IBull ,,ra-s is :i a i. ve collillioi ter'in ill ll iei anld
refo's (o sto evvrnl -pec.i, o ,dt ,_,-i s.
Tille oeulreice ol' weeviils on, 1 W ait lle'< -.wale Tr> (WOW "- wia,./i
*nu'nili'i i<, I1111 was 6ir-t o!)ser'edl !A\ M r. N wevle a( lalat e Q \ trlhIr.
LA. W hliilv similar to l'Vnlisihmi hlave lieell inadle v ilie writer at
Cl'(w"1e\". 1;t.. awl I, m'itme ili ll'. .\rk., (l ieinlinis of thle 1i:ra-s at Cr(l vlwy ]re-enled (' M ml. timll.hi ) ol (lie plant. Thi> f .. fa i,\'ever. a:yV Wit\, lieen dis-
cove'red I Mr. NeAMl I \wo year," lprevosly al llthe :ainm plaTe where
he fot' dlaii i n esV( i nfe tin lie roots" o a wwi ky It i -i il \\'iic'li lie was
inclined to re1, ard ast alloth lr -pccices.
A "-M (I ,lri il', tilt, stcasor l 1n 1 at ('r w ) lev, IV.W i e writer i'onnild
two other '-!,,i,- olf K a"> which alll ted ( e w e, vo il-' t'rOi lielt.
rilaret oie planthi ()Ae of llief e \these Ivy- ')er ida l'rus- (C ll '1 rA .,
duy,,ii'n It gTtOW ol a ievee in a i.ce lield w\\ cl i had l i eoi hadrlolov
omr' illh v\y with the tlood water. As aill ate pl li0 10"e madeV tAo
,,rov il on tie ( 11 la d previom I t 111e row "rol. it, occlnrecl e Undvl.r
lfhu h l conditions \ai excepAtiwt lo na l, aw l no lar\;e =T'ee fo ld A Mt-l
in." tlhe roots. It con iot lie co sideieId a a prop r liaahot plant. In
tlIe other 0t-c. a u t iltI- of \\- aler irahl !'r "," lrdolilated ll\" i a spewies
of Syntlheris il, wais makingl ;a depit rat, -il I'oll --V r existelnce

VIE kill! "\'A IA. 1 WFEVIL,.


within a flooded rice field. Leaving evidently started into growth
before the field became irrigated, tlis crab grass was able to live in a
depth of about 0 inches of water. Not only were the leaves severely
fed upon by weevils, but the roots were attacked by larvaw.
Since thle growing of rice others special in Iuceenmits for the breediiig
of thlie weevil, due to the attractioiin of thlie plants and the wet condi-
tions which they demand for growth, rice has Ibecome the favorite
food plant of the insect. D)irectlyv after the rice fields are flooded
flie weevils appear and commeniie feeding oni the leaves of the y,,iii,
plan I ts. In southern Louisialna, where much of the water is supplied
by canals, the irrigation of rice fieldls usually begins inll the first week
of May, but the time of turning on water in different fields is often
later, the flooding somnietinies not being done until iiin J1uly to accord
with late planting. Where water is pullitped onlito the fields, a steady
flow ullUst 1ie maintained for several davs before any large area of land
can lie inumndated. Thle flooding of fields in Arkanlsas is not generally
effected earlier than tlhe middle of Juine.
By following tlhe application of water inll every field the weevils
gather most inulerously on plant that stand in thlie depressions and
lower portions having tile deepest flood. Mr\. Ilood has counted as
limany as IS weevils oi a s'tool and 12 orl a 'single plant. An average
of at lea-t 1 weevil to every 5 ) or (; plants in one field has been
reckoned by Ali. Newell. Some inclination to avoid direct sunlight
duiiing days of hot weather is sliowi by the weevils, as they seem to
l)prefer positions in the shade of thlie plants and under the surface of
the water.
They are rather sl: 'i-l except, when swimming and are disposed
to feigr n death if taken in the hanl. They show no inclination to
fly duriiing the day and even refti-e to expand the wing- on liiig
tossed into the air. Passage between separate plants is accomplished
in thlie daytime bv swimminglll. That they can flly for long di-aiuu'v,-.
however, is clearly proven by their attraction to artificial lights at
niidht. This wn)l1sity will be more fully discussed with reference
to methods of control. Invasion of fields musit therefore be con-
suininliated at iight.
Rice is attacked in thlie same manner as other sii milar host plants
anid lthe effects of the feediig by the adults are soon iianifested by
lie a ippeal raice of scars onl the leaves. (Fig. 1. f.) In tlie act of feed-
ing, the weevil braces its body firmly o)i the upper side of a leaf, and
Im'oing slowly forwaX'rd in a longitudinal direction either up or down
the blade, it eliows out the epidermiis and produces a scar, leaving

TIlH lMCIF! AT \I i\\ 1. 1 Vl.

thn unIIII 'idc' til IIatIc'nI. I1Thc- I:c r- aI 1 vI r I aI' I rI'I X Ic iI, 12 i o l;t
1o Widtler t lini Ithe' s1p1 ait of tilh mn4tdil)'. !4,liIiit tilt' X\;ryX in kql'4 lli
t'N nIII ;a wIlmall fraltini "f ;til inch top umorc tlhan, inchc{':. hlcpemlling,
iI the tit lle ill which the insect' l,'a '- ill ft'vdini!'. \\l'] n e llO w lin
undeh t ,id' drit ilhi, 11' -w'ith'. it -1li- i, 1i fomi,- nI <, tin g i_, 2
1tho14u1 olut1 tilt' injulrd'l lpu'4'. Til .'..v e lilt lii} w i) o iMll h +,'I
fo14li iI f dr A l4 IuII= n Wi.'-, tl1 sc':a 1t'4'{ im4 un nei14'1i'To 1i1i(' i tol 1
Ca1 -{' \\iltilI2 hn 1Id t i 2. Aal tI(- prtvi'n 1 s ieer l44l1r yoi 11'" plants rili'
th1 lin tlhte 4'41ti'-'ir t't' i 'I ,i'r \, Ill.
M \I'NI \I M tXN( IlI l I4 li>\+
l'll 'h 1lIu 11 1tt lir I|>rr'i AI i 1 lii+l t X t 'ih it."'i l- '1ii in in ninttinIg+ tak-^ ])ifce <,it uvt'arl\ all +A im- iii- \\wl< it a tiale anidI Wtin&'
hapItipenl to Ille t. a ll tt I alli- 1tIl tlv o ai lll44l Xl t IV' 1 1:' T he '1viti
fInialt' crawl o\1 n ll i1t -t't i t' 4 41 14'tofl l a1 1 :I d viiihtt lv i li)-it
their e'-2 -in'1 lY ill ai | i411iti11 4 tl i :it ii' :' i ti -t in :i r tui i r.
NI v,.'II4 14 1a i n'loiAIit{' tl t h,' li l > I; '- 4 i4 1 d lt v.4 ac-Iil- l Ii, 'lX 1114 X h'-
liV'cvc t1o I. fl'qitlheS Iit",' l,ttqj,- ("It on the n inu- l1,ho\v tlh water
lim. \l. l,4t1 :INi lI' th 1'iO w It Ix+' avv X trl 14l4c1 ";[)d' '. i441 44f
t'liii ]."'- \\XIXi1 they apIpa' 1 nt1' l yt IX lto4I! k to o\i \ i )-it 01MI vice 'oo('-
w i llili .1lat--' t1ul4'-,. l'l:. i w \Iil thn4 i -I M ii 4 ", I %i'li4414 l11 1 'i'
unit a pI ace on a 4 1 1" mi d, att 1" 41 1 it for a11 ;Aiml i iIIHlt '. 1l4il4 Ale
"re.' her' Ii"lod t4ip|q,, ti, il\. iandI |1 p I ii s Ioo (lh. ;oik x o
ni nl I \'1 1tl<' 14Tlr I, ll t -IM' l1a1 t'Kid' li ot4 1. M rI1. 0Iloo li:i- 1 l ',41144
lhiit1 ]i4' "it\\ tIlt 44XI!44'-'11441 ill 1114, 1441141 1 114 ;i 1}tt t 1i+t+ I + 1 '' ;ll 4 ll
tlat lie saw1 tl14 1o41'iio iior in t o o' a Iirc\ ii win.1a aj4n;l;r organ 111-
wtto {d into the Ili WXithout anV ai4)a1'lii'l po\t(cll4lt l'Xol 5 -'c1 I 141-' IO '4'4lt,1 t \l' i i e- ,i '
was wit ihdrawnVl The wril lit ttlit 1 1;d14l4c t) -e t ii 4 iX p ,i !4l.1
e xtenidled t or to dh, t a't<' ait ''22n X ill (vi1,taiit1. Tliw wXrt\ il IllaX v I iili
up aio vclX w1t1, XA l lr i af tier ca: l op'l'atio and I '-t lo' a hl 12 (w li4rl't
l 'io t. (w continue' lit'r ,aril/ 1ini- ;411411 r11 t I 1441- forl' a XX1hilt. {)aIl'
w Xev il staved 1 iiltoi tl I'e root- 1'41 I.- iinitlt 's.
Tloh' 4 hvit'' limitt wi- d4 i-i2 (,l ad11 1-44 lIv tl4 XX 11141 wri lt'r for o4tlNr jill
tl1e ltn'tli4tod of oMVXA"Ali4o il 1i y tllr w y\v ilV- ill trai':1 i'1 in 1i2'i't' 2.
I itn i l-t''rl ict ol a 14i 4 al" S H 4iiil) i iii \ll1 \ \;- |1la 'd pI lli ig-' it 11 ;i
si-atl'r aim 14 4'i' nillt' 1tt l :t lit' l);s<-' w itlh |l4a1 ( lr olf Pari-. \ A > iro -llj)p
port XXiti ll 1441 li i ilt() 1 loo1 o,4 ti44 1144 "r4p41 -iz /' 1for "lt vii, ia
cl4o4 d- ot t,1 1l211'- 1(ul4'- o' wi th an inch dia:m1 1 41:i lt I4'ill, icd to4
li l1l Il 1 o' 1444 441 a 4i41in1 1 ric p liant ill w ater:'. \X;- lli'( 1t 44ll, il lil('
ce.'nter'l of 1l14 -'1il't't. 1i11 lthX t'' I'14end oif tihe 1upllorl t wX;I :l"o ]'4 t ill
a p l>' 4 to1 I>a'i'' 0l)illlim'-"- aftertl'l I 2,' 4? -cl ill tie pla-l- B'i l l ii'4;
olf a; -tlI ti't ot Ii n ul er 1 lpar1' t orf t ll t'il,. il 44(i4 14 l.XXd 1\ 44,l
thrl igdili lhOw top of tlihc liituit v into) I A la:nli |io th+ilt io w i i lirt+
"irn loop) ;>ld al," ii,+\tq lto riii! clo- iii-lpectioin of root- and
ili40t'1, llsil f Ait \\di'li >\14 r dh'X ii''.l2
pIl': ; Oir. 1 .2' Q I


Mr. IHooi lia-s ,,tattel that the lairve are first found in Ithe. rice fields
front (ole lI hrn wes t- f a'ter the turning onl of the water, the
time of their inception varying
.... .with the weather. Hot weather
".-----------..' accelerate., their development.
-'" .. -- The yonli lar e, which have
"'' "- 7 dou!btle-s hatched from eggs, laid
\ [ 'i in t]lie Foots. I begin to feed( on
1 I ; i thlem, and ill coIr-,e of time a-
I i the larva inerean-e in size they
I, I, (devour or wovelarge portions
of the root .v:-tem. Theyv have
S! .. been known to oat hole(- in large
1 l, jOoi rice root, and burrow into them.
; iMr. W. I). Pierce, at Beaimnonit,
\\". -Tex., in 1901, found Nvigoru-ls
I'j, I larvw con etliniiin_" the entire inl-
i ------ c re i Of tlw roots. Figure 1.
,. 0i\-e, ;I 'eprx-entation of s0 x
--------/ feedingi2 hoile, nl"ade a>t a (l1-i alice
"*.., '" not more I a1nl oni. -fourth of :in
t-' .i- il-l apl i :rt )i. ;lhood view td
-" ;''" /7 the 'm. >I',, om on methods of
;,' i, attack r I-ill xin p 1rmting of tOe
roots. ,Itilr k lhich I he severed
l ..1 0)1po rtio ott ant (li tle rV ainin
.* ~ .' :. *--. parts al;ev f -ritler marred witlli
'" )I feeding, -cars. t tliis stale tlhe
^ho tld ohf 1it, plant 11)pon the -oil
t& r~1e a tI-t Ithe~ron 11
..... e e. is ,' -at i i weall-kened and it can
-- .........- __ .,.... 1)e Q l p dh from ilhe roundd with

--.. ord the root v-tem \ woree en-
.. ... rtirelv e-tro'v(,yel anld the rice
Ft,. 2 na p-tctimnny ca- Tor rn1it< 1tlant-s floate-d in the water.
Iti! oi --viii i,< riio wnt r-w 'il: I, Th' injurise- dt (l ]x thl e h ar\-v
{; ~ ~ ~ ~ ~ i- c,111- il1(, ](v" of Ov, r](10: ,\''Y{ C}t;/lit
,:i .r ..i r'ir.: ',. i.hi-s mo ,: n .. wn- tir-t cause {lil leave-.s o- tile vie'
-;,i:',,i : r tc Iti plits to Iurn a pale fellow a1ntd
,;;tI.- : /. ,i nin..r l>,>,ndl; i. j. l .....l lh's fI',-,.- l1~ n s it lll 1/ ,) h ye lo an
in. (ioriiit:al.) droop). thle lower blades often
restI ig" oil tIe water. With
xevI nt' !Liv -uMte of thle leave, lmaiV die. Tl-ese effect-.s inll tle ie tlds
lt-te>rt(e ti 1]roo10miced oil plalnth s go)wvilng ill dpe:--ioi-s :ld] low
tporiioll- (4 ile l laIntl il1 wiich tlel water firt flowedi and where it


stands d14o'p"-t. .\' previo+1ii-I nul4t'olo1 Id. -in li place' ar' 11o01-t,
attraltive it1 t aduiltt. \Vh re Ire t dullic adult iMc ir ti l i iiih To ly
thei lanr'x l t1t-I li4 .ey,+tcdl t, lollow, itn gl,4cat ml1 i1 14'e Ill 44 S1t" -
q(111 cl ie i st e 1 44 er4 it' l t* 4 lt IIrval inI''tal : i ;, i-4 I'- MI',it l\ :1 vellowI v
:casit 4if 14 h'Iaxv'- xtwenlding in lbovaid 1I4tr1iak- ;iml- ; furro4,\\
while s1ot-, rl" a ,i of yvlll ,i-h phlla ts al-- l colliec vi-ildly :ap-
Ipareo within tlhe hollowv, awdl simk. olr the il; id. Tln,-, -iiAis ot,
injury have appeared in lielils after *A( dayv- "f t~iii;.loll ondi-
ntt ll 'v\ (lie al,;ir '< do m lh lVi mi rll intm'y) i I ( ll ,21j l i l K lan- t ,in lil
(I In, i '] tm il tIhe wat er ha,, I i mm Iw'tood at I' ;al'; ( imoil l i t
If iit >; o t lo r t e roo sl an i I oa l 'tim i plaitil lia'. 1. it44- 111lo 1+vl1
is 14 4 t 1tu -4. llhi t awi- t4r4 1it, rhoi1, laiil 4 )4! 441 ;, 4-ti4 ro4 1' g Mill ) 'WVp r
' 11 o l is are lIll o1t to r'-n4c (tl e "no' s 4l4tr'd. and on),it1' (lit, c411 t 41 -~;i-t
tio f ol' ;ittack!- the iljotred plant rev', s. Ives io -;>i, d l ") r awl imake, :i M ateitd a+rowt,> n-t all, r (dr the un'lul|tal gIrow tli 'r 1 1 laii. i i' ll + ti, 1, it- iwth 1l! a. ai thl4 itrrie -
l4ar lilti lyl 4 heads' licads. is 1 i44 4util: i' 1 o lltc dltll4iii ;dI 41 l c1 1 t:r4 of'
tihe larval at tacks. I I;-N ^ l r o -i uiti ll irc('t-.;txril\l I>, d'lal'd unlil :all
(lie li, ad are rip tilnu invol\vini, o 1t114' iI' ol' x o- to llir iior4tli x \violx
from s'torins or other t;>l.M'S.
F'iirt- rit oi', r t. lthe al(;Ilc onl tit inrotl- o" tc cr of ^tm l Ip tints imt-
i\''i l|)lqo ,r -txooling or l'o'2 1 r4t1oln o1f 'stlmI -s. Il m'14 i1pak4i4 wi\'.i t
inorinal l)litl-, lti ^ l(dint lh, itan la. ll ; i. i -an *t In- O wn 's o 2'i"i hu a tQool
tiit lias u intcrd d ailli; c. Slt~irl;ld'(1 (d' ltm. !r IWO is llii'd'fo 140<': l ) i)V
ti t'in failure 4 olf 11i i 1 i(Ui11 [ I >laIt' t t- it jlt' 't41' ai falro l pidl 1 ol 4 'Itti"'.
The famt tii tha e lOw rva im a largi lyv. r,-pol, il- i ot'ar ai ^ at d ,ltolicionc+y
o1 vi xld ini t 4i 4 11"il'14 a 1 i 1tiprl'iI-io\ n olr tin,' aiil Int1
od' loss cat 14ii- Icd 1\ llhY 1< in2'l.

1il VI .]U41 N r

    'rho length of vliitc nt><|Uird for tlhe devi'lopit'iil of lif wth c mil
    frontii a fr'll\' -4 laid t)10 Wtc- ,!+i t li T idi'in 4 i44 li, M 1 otiiti'tir'1 o1:4 lar\;> s 1 i 1 ni i. 1A ter
    St lo I'-} 1(', c l44 ( to41Ioili i. all l 4 io1 1 1 t 1 :xc <(1444 10 1Li\- would
    ljI ol d al l\ 1' 1 I l il tin". for an ilt 1'4' I i' o11i 1 i -til ti't4ll4I411 411t 1114 lo. ilt.
    D])e loIaim ut is I7 Ash i' l \', iAli 1i1" ad, la c ol' ho, t of Wl litr ">'ItII tlie
    W at't and so6i lt1 c iti \\K;-'01. W l W iiallv iio lnul i0l ,l lt ;-i or -o.m'll
    ,^'%tlois nfter ood-5 = thi iall V I r' to| lic o ,l'v+r al:> iii f _i' ro\lli tAlawl
    appear ready Il'r pupalion, Naltli 'lu l Iupir ll t\' have I',i l ii l id A a ib ld
    tlihal a i the tliih ad l, O wn irri"l- d I'ot r A oniv live ",Pkl -. Ii ldt [ imi",-
    tiol for 1li6 )nimIal vlai't thin larvalf\+ il a c'll ir e tlin thie in l o iit -l the
    rot s or at tihe tjp I ll 41 i4-. :la dI MI 11lo<4 1 a:-. 41--1 i 1dt lit i 1lit 1TO i
    l:ia-I two or ,1 0 til4 '!1 w' 4 l l'14i4' it li(l n t: N1, t t' ,. '-',' I4r 4 or lhe
    adult lai J 1j 4<4'.


    With the aim of working out thle details of development of the
    larval and pupal'stages, a number of larvie were placed on the roots
    of young rice plants, each of which was set in water within a glass
    tube, the tubes Ieing simply stood in a holder. Attempts to carry
    through the development of pllpa from larva' wvhlen subjected to con-
    stant, exposure to light proved only partially successful, but better
    progress, although still lackii ,' completeness, was made after shield-
    ing tlie tubes from light and supplying a small amount of earth with
    the roots and water.
    Adults as well as partially and full grown larva and also without
    doubt the pupa, occur in many fields up to the time of dr:Aitii- for
    harvest. With late crs in the coast region, however, and in the
    fields of Arkansas on account of the dilfferen'e of the season in that
    State, the numlnber (of weevils in aIll these stages diminishes about the
    time when the plants berin ito head in the latter part of An"ii-t.
    Weevils roundly in HielIs after tlie drawing off of water to permit
    lharvesting are apt to be freshlv emerged individuals of a new gen-
    evatioin. From a collection of infes-ed roots obtained 1) v Mri. Pierce
    at Beanmonit, Tex., Jun, e i s. 19)4, adults etmer,'ed as early as July 2
    followingr. In a-e su'h early (ii i' ,1 weevx ils breed at once. they
    have a clali('e to produce a secod' generation ili a season, lIovided
    they find late Ilooded Held,, or suitable water hloles. At St utpigart,
    Ark., on September 12. Mr. Ilood found roots of rice infested by a
    few larvae which lie reigardedl as rel)reentatives of a second genera-
    tin. Theli last larva found Ax the writer during, his stay at Crow-
    ley, La., was taken SeptenOmber 2.. While the weevils that .nti,., il
    lJuidl polssiblydv lay eggs' for a second generation, the species is prilln-
    cipally propagated in one yearly gweileratioll.
    In Ihe sprig, e. elore manyv of tihe rie fields were flooded. Mr. Hood
    coll'tdI adulns (om gonss'es andl i'e Imte ']rowxiI 2; in glitches aml other
    llice' co(nitininiii water. Since tie weevils have inot leeni known to
    breedl in su'i places until thlie soil and waterr hecoeiit tuflicientlv ,varlm.
    at which lilie the ftliodinig of)1 re fields is well under way. th(e dedmluc-
    tio ii i i(ade (ilhal how telnpttliql'el p 1i4) lhis timle exert a restrictive
    inlivlutce p)oln bleediling.
    'xa:inat ionl of oo(ts ol red rice andi oilier plantl- i'fowig" in a
    coist;antl' flooded ditch a(t ("i',whey, La.. ont ()ctoer ;, failed to dis-
    'clos' aiv 'vidletues of inifeblstation ait iie tiiie. These i'esults show
    <'onclisive'lv that the \wexvil does -n tbee :i( ll tis timnie of vear even
    ill most iiav orale 1, ituation,-'. Not onilv were tlie a(ulitIs ab-ent, but
    tihe lack or' tfeliniy scat's on liIe leaves denoted that they had not
    viitIed there fort' o li ti ue.

    THE tl' F \W F It \i-\ lV l.

    The fact thiat ad Ilts live tIlr-mgl. oit the ,reater |Iirt "f has lven demonstrated several times. In aIl experiment with speci-
    l'mens collec ted al t MNA=y Tet'x.. AprIH'il l A I N. Mr. Q. W. brothers
    SUncc(teeddc d in keeping tKe wevtils al lve 1)v furniihiiit, ir fr f(ool
    until after (lie niddlh of Jily. W eevils condinti l ritun V phintAs I,
    M r. lHo ld at (ro w v, ., lQ .. l Iy liS l Ilnter llian tlie tiddlt <,il
    Selptemler. and tie writer las indmhe a corre,spondijlgr ret'dl rover-
    il :|a period from) July II to S epl)(te er "21.
    The common ablo.m'c if Amot Acnl y or' fr-h -itgrn, i, fee,,ding tIv
    .dlllts latl in 1l6 'a(.-"- ua t; H Mile wKlhen (lt I ne\V reine' thion of"
    devils is expeltel to ct ierge throws much doibt on the ui, e:-tlionl ()'
    their taking a 'ny A lnd tl. .\( least tint t v do) niot re ain lbnoy ot Al&
    plants, and thle few feeding, scars tal tha ay appear o have at tlie tO ne arc likely, prod' u ed lI, li lii i adu lts- of the 4liet ld ^'i-
    erationa + \ vA y arly\ o verla pi)[)ll" I' of w i" ,litns 11 lln e Adult sIna e evi-
    dently tv occurs. Few -'pe'imnl- thlat nli +lt he r-0' 'arded as l',-lilv
    t,,, , -, d w eve, ils lhav+ lwee fo nld ill the liieldls. Thlns we taken I>,.
    Mr. 1 lood, hidli, iln thle cracks of the 'roin" a l'te" tle \\t later lua'l lWtee
    dr ine,,,l 0 0' 1 tie fiel d for ha, r\estti 1,1^. I'o.'.iln lv ,m e of" tlic-e` \,'A w 'il'
    -lrn to my hI" lWm ii I ,l t> ,I a l ii"l(. Anv la>s capt" IlI ;o "m "f w \ il IIi 14 -V
    m adl e om tlw li. iht (Id' Se[)!e iil! "I It a ew 'i i l aIo l'+ w'e "i l<
    occurs mo r &.hidct W.+c o"Ir it li:- lNeul lIiilil. A lie (pii-tlon i-. V W at In'-
    ,W "n's Or till mi a 11 il iltll ,ev +o nt i lnt li mern io ll +/
    11 1 1:1 .IN ; \ I N .
    muiiti, tll t'fall antd water (' Ir1 I) M r. Ilooml made ,xan ilallions
    Oft la c whicI I -it 'il -cr\'c aI- hihtrnnt itl 1 luarite'-. TI'e
    nmaterial.- vxamiii d, inclde rice t 't)hlklh. moo-. dirt Ai tlhe 0I1ld .
    s.ntraw'tanc s (loth AIId =i1d Ai\', ). i! At& Ailmie \- ( ct;ildtl t m itll r
    along,; levte'. and Spanish Ino+-:. No \v l' were\ f- flo nd lili Crt l in
    teXrepl in 1 1he SpA ni >h moss lw ill. lii we\hvcr. n lfforde, d n Ai t c llc- l
    siellter. Js tlihe I'olhow niL, lalK Mil;"ttcd4 ol T>l'lv tK 111111V A at ( :'11'1 .
    I O.., itt -illo\\ 'Q V
    +:,1 .++ l r i : :+ l i ,l*f til I i f i+ ]+ ++ + il i i s ,i f /li + :+ ] :: + + t,, t]ll i5 + l l 11! l l i : "ir i i l 1 1 1

    N .v l '. '+' *+ + *+ *+ *++ *+ * * :,, *
    l~~~~~~~~~~~~ ~~~~~~ ~ l .'' .... ....... .; .' +;)., .


    As. indicated by the preceding table, several thousaiid weevils may
    hiernilate in lthe llmoss- on a single tree. The appearance of large
    imbliers of wieev ils in rice fiehlds when they are first flooded has led
    to the opini tii that tle pest c(mipletes one generation on ]iost plants
    collier than rice before this l time. But is already pointed out. no
    Cvielce has lieeil secullred that will sustain thills view. Abundanice of
    the weevils is probably dilue t to heir successful survival thi',,l the
    wiilter anlld emIerQece from hibhterlation.
    Oie refc recwe in literature menitioins the occurrence of adults in
    Xwit ertilie uildler old leaves amd other shIelter in drier places near the
    'swamps." The fitdinig of one adult in litter 1e iath rich stubble is
    record y V Mr. I). I.. Van DI)ine as the result of searchilng for half
    of :a dav at Stewart. Tex.. onl October 2) 190!). iEntrance into h1iber-
    llatim is 1probablyh not begun mulillch bIefore tlihe time when tlie nights
    are told enough foi frost. Not a single weevil could be found by
    ti e writer in a collect ionl of Spaniih moss obtained on September 29,
    at Crowley. La.. a:1d in the precedling1 sprinii after thle fir-t weevils
    :a1ppeareId lMr. flood was una:ille to find any -lpecimens- rei,.ii.iiLii in
    the nlios-.
    B1-sides birdl- n1 emlviI is known to feed OIn the mature weevils.
    a:lth oiih tlie siakes and fro2-s w hi'ch frequielit tile fields probably
    do, ,. BIlird dropplillgs fouildl 1 tbv Mrl. IHood in a rice field at Stutt-
    gaIr. Ark.. o(lt >eptlenll'r 12 ctn-isted largely of in-ect remains. those
    o,)f t e rie i XXnitr-wXeevil beiig Ilie il,)ti alunIIIialit. Iowmever, two
    perfect sIpecillicle' of thlie weevil were relmovedl from tlie droppllingrs
    alld )nle xx a, fouindl to Jte alive. Accordlillg1 to record(- in the BIiological
    SuilveY. lils weeXil is eCaten 1,v the lho1,-lhilled marsh wreln (Fl T +bina-
    i.@Iyfc'f t i 1 i ll(!') ai t thle iialhlar'ld iick (A l st p/t,/r/, >'/ 1 i,p ').
    )Ow\iii to heir 'owitclealmentI ill 1l11(li e larlva ail pll)pa areI secure
    fro'm niell si'. Vlihll iifist1ed rools are pulled for exainllationll 1and
    l:larvx :c \vaXl wIedl out ainy innoIil IiO t aIt lappell io Ihe present in tie
    wX:i1tir wXill -1 ,Tedilv -napi liei lainC g bodies. ltl'edaieouiI larva' of
    at' i ,,lect'hl] v iihcli :i]so :laion) ltl iln lttlO ed fields, s-Itr iggie with ol( e
    a!,!othr (o0 1,sseOsio of a weevil larva!. If flese ]el'etl- al the
    seve>al .indsl- (if rapaciou> witle .'s; \ecre adapted for hMirrowi\igl ill
    tile im iIt l ind h: ing lli the lrice lo ts, -. tilhev would li) very v tl I 'L
    detiovet i'. to(f 114!1i weevil liarvwa adt pllupa'. Bllut their habit of hulint-
    111i;_ i li] h t) tIIl op i'c (f' XVsiCat I'r rellders tlheni of little o i o service'
    1111ifa in~ line XXeev\il.
    lRA N I NtGOl Tl 11 IF I It S.
    A>. poittied ,ilt itll tlie study of llie life history, the existence o4 til'
    larvu ;Itlid likewise I lle liUpe de!pend s uponll I saturaltion of the soil.

    If tOi -il Alri- o fcr tKw lIrn 1
    tlh ", -+>,H 'll. v ll t' : th%'l T O 1' "If d
    to i ll '" m ol it < ; l'l t !" ; t l l "
    1""l 1>,v C <>1. .oi t, I cri ,. a rU!, t1
    Sihmlr -Ar 1,v 1)r. l lv. ;I l nl lnftr l -h
    14"ne of 11", riro' y momn' in IWOII

    1l :1 ; i l ,
    Ia~ o ,_
    AcI !

    itld ft M W I.,1
    p 4il1 I .- 1 4t1 f'T (144441V'
    t:in ln. M iii'v nr ,I r'

    o +ir{ j ( > l'Q, t iKII!

    XVI tl l t441 I- t+l of
    1111illl~< 1 'u 04 lU; '

    S 1 1 I'

    tIoll I >+W

    I rt l ii, I :I
    WIl tN
    Al \V>rv

    OI m iU rllo -t li
    '-- 114' r 1 ii+ i l14' \4 ;m t o 6 '
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    i_ i

    -01 11. w 11
    f-1 l K v III

    Vol No .4

    - o


    """: hr-:
    ;11 C I Fi !


    THE NlIC WATEN \V t 'lMVlI.


    1 ++

    tiu:l nf lie l i :li )(r o f 1mt'v


    I.svI'rs OF D1RAINING.
    Conclusive obtserMvations upon tests of draliii,- conducted by the
    writer oir uiider his instructions during the season of 1911 are pre-
    sented in thle followini- statements.
    At ('owley. I.v a., n June 9. a rice -rower drained so;e, parts of
    hi i held of arly i planted Hon(duras rice in which fully one-fifth of the
    planlt-s, then at :l height of 1N to 1. inches. showed yellow blades.
    Thel roots laId lwen rather severely pruned, but enough remained
    iogether with eicwlv grown ones to permit dr!iniii,-, with safety.
    A m4i iany as six and seven lirvxe infested tlie roots of a stool. Reflood-
    ing wXas etl'cted Julune 1!>. after a 1)eriod of dryingi which had lasted
    nearly 10 das. QIlite a n)oticeablle difference existed between thlie
    drained and undrained rice oin July 21. The plants in the drained
    areas had neearly all headed ulit uniformly, while most of tihe lm-
    drained rice was behind in growth either mot havig headed or hav-
    ing helcad-, just forced :and blooniingl. Regarding" recovery, the ownei
    said tiat tie phlits which grew ill tlie fresh water after refloodinlg
    soon lo(t llhcir vcllow color and took on a vigorous growth of healthy
    grcee1, 1ut in lie iundlraiiied parts with a:llidinig xxater the plants re-
    covered lluch more s.l(owlv. At harvest time tlie owner estimated
    ]i- best yield on land tilt lId lecn di'ainied to check the weevil
    In Hie field of a:lliother ro(Xwer, o iwever, results were l(ot so suc-
    ce--sfu.i, Thel e small y oulli, plants w cin iot injured badlv and
    showed oIv ll il'i)pieni spots alnd streaks of weak yellow color. This
    was a \v:riety of Jaanli We. IThel field x:ls drained May 29 and re-
    flooded Juliie iving l a di(iig of 10 davs. Onlle week after rellood-
    itI tlie plaiit had iakei oni : faIres green color, anld thle infestation of
    tiem ISiilu li ilired root- haid 1beli reductied to a minIIiui iiiii, :as s-liowli
    hv tile ieairly IoaII'i: 1 g(vowthi. Owing evideitlv to :i second infesta-
    tioli, durii wlixt x no draiiigll x was dollne, anit irregulir belated growtth
    waIs disphlayved at lieaIldillg lilln. Whether tle outco(lme night, have
    1been woxsx e without ally d, a iiii'n" caill only Ie surilliscd.
    Actin ll under: coopej)cIative' :'nreement. MAr. (. (H. Iaskell reported
    somei very importailt results of his examinations at Alinivra, Ark.
    )Oni drainii" ;i field Jiilxy v( lhe found 2) larv;' ()o the roots of 25
    st(oo s. (Oni thfloodilig tlhe field July 2S lie found (ilo nv l(wo lairvax (ni the
    sami e l mll er of r'oots. Thie result wxaus a(ccoliill lseid lix *,.ilt days of
    d railiil aiii a d duringg. A stool usually l1 'Odliced tive stalks oi' steins.
    Bvy (:lcilalatiir' perceliint'Is Osl'll\- iaiiiir liuiist havle Il reditced he plroplortionl of lairvn' front
    20 per (con! to 1.(6 per cenlt.
    Aqiain, lon drainiinl" a field Jiulv 2- 'M[r. llaskell found .) lairvw on oots( oif 2.) stools, buit )on relhoodiing tie field July \31 lie found Ito
    1Io1 liT l haIVeS per 2.7 stools. The draining anll d dryin therefore

    I II k I I (1 I \AT I W 1. I\ V I I'.

    lasted six il~ii.. and 1,1e la ltina (" 1 ; I)' > 'l live itllk-, at ;a -nodl the
    iml+-~ lt, ex, nibmi mitit l this rice ("i A- oim+ t 1. thI m,' ,)so d d v d ,f mt"llhoodiir,.
    ,Y ive sulbstatntial m\ h p 4d n to'I reduction ,of la mt I, ;e 11 ,,r l-P~)on d1 in1ItL,,
    nuIiilwts. thr ,ount rn-t ig inl 3' larvaii oi tint oot ,' )of i >n -i lkn.
    At line lItNlAl. Ark., on An\ ils, 't (li,' th writa r ande, e\amuiiiation-i
    if) ; rice i'hld thaiti lItil been Wl HOMcd oi'r li\ve dl;i\+v )it dlie ro',m ul'
    10." tail].-. (,lI v nrine l;.ir ;!' \\la m 'e w 'erel ;in iiv h ol,' 111 'c t;tta i ion t i',r -
    I'"ro c 'iiiillt( tod 0 |) a roxiiiatlcl\y 9> Irr cmiit. Th'le o\nt r -twianl iL;it
    Mx.l'oire t(lr iiiln.+u tw,'o ;indt h i>rt(, o;i'\' ccu on t*i'red on ;i slodl. ( ';It*l ult;itlHit
    live> -tailk, l ,,| r -, tl. thll, le l't ;-t l loll tilul tol, li l o1n ]lnl \ > ll' ]'l il h- t lh i,
    .,., l )( ,r l c nto In so> v ln lncc- l lithe gn,'I' xvi;>-. s+Iill :;turatol, N onitd 1> l )ot
    of it \Vzm.- still' mnud. h' t tl he lic d itni_' rca i]]\" v '= AO a rcdhrltlt i 11
    thle Ii1 l H'r11 ol' If itr\\;. by\" h'eatlh \v :s> c\ ideniced lWV thein li t,,_,' ol0lf i\o
    d( MlI on"I ;i l s'm ite (d ti k e li (O Wtc ','llu'l \",+\'i L a ;i f i ab ottitl rt+ 'i v It)
    WIi Y. Not It \Vrota were llmdl lv rutit ;i ,d tlt( drau inil I't'+-';liii ;il ;ani op, -
    portunW timw:. 'Tit' l|)iiinpliti wi\ate ol on itih lihci \\"a, ;i ,.>ui ilm
    A 1l..,,.t ". l>% lt it Wa\ tol +l illy 1lh)(010 until a1 l0\" ,lay ilt r. Vs' IN T ,.
    dr* v+ii. covered m m.>'('i days\' at Ona t. 31o rain eill durint'i l ln- t i iiuw.
    andl the. roundd lhad I.. w_',on to Nuicttk Ir drying t. Thlt, rc:-ut- wot' lm
    consitis crfl \v.rv lwn'iu'llial. as the' lI'n\'w ";a sed( no KI'r Mu'r trouldlc nit
    lli c e ric l ictdcd oit S+icil dly.

    [[I )( IS (ol 0 N.[N\ ; WAV II'I.

    lirvtt oliscr\ a it in-. as w\cHt]l a-, the htm iltvcin- ol vro\vvi-. hiaIvo
    b)roughtltl out ll) c fact tlW at rice '1o\\ il^ iI riiitingit '.\ t 'lr su-rl]'s hlilte
    front weevil attacks. III lh >,e vas-t. ho\weveqr, 1o) co',iiieraile ;ie
    ha,.l pet lhim, sen in wii, lit tie water flowed with ;iy\' piereptildlc cit+-
    r'nt. '1') maintlain a di-tinct inoiti;' flood over a lart'_v tfivld womild
    lre 1tire ain iti iitllst s-upl))I o water. Thie iffl lnnccs thlat liVi\' lhiaen
    >lserv<'d were (oifindl to" -limts or smiiiall latss coveredd ly the inlow
    of w;iter from a canal or ,hitc. In spn-di) ; (Into a TOeld f'h onn ati
    inlet t(le Tc ien >oon ll ],>O flc t' and an vloy w tem pl titlure. ere
    Scool llow ()1' water is pImpiild ro a well VoineNI tl lv onto a Sd lite
    low telrititvlritre seen to exert a coniilrlln faW otl ia il-i ]iln'f-li-
    i, W Iliat 16tne cai, ;ciam r ae. Ion% heca s- the icev Ainaiit N\\arin Itn-
    l)er;/it tre- for \iiroron, growtii-hr and thhe sun het i ] tl p e;itl, I --ict tihe
    cool area.

    Iltll t'W 1 Ho D Il' AND SIItA1.1 0W t l,)1 i| NK AND M) s t \I N \.
    IDeep water and -I ,.i- ilmt water grjfieatly 'v-or d-velopinciit of
    w'cevil-y .\- already pointdl (oil. rime in spots o ae' id" o1,ee1 i lp m m!-
    in s i", most -ervly attaiked. Severity orl attacks is- espleially

    iaiirked ill -hliallow Vwater almost as miich i s, ill deep water when
    citherl lecomies stagnant1lil. III a field tlihat iadi received only a scant
    suppi ilyof watiel, which iii fact limeriely filled the lov>" places although
    keep)ilig '11 (1 li-' roulilild Sioaked. very few laira', could be ffo1nid.
    Mo-st of 1li-' c. l8vw' o('Cc'irred oll rools of weak 1)plaitS inI thle Pools,
    wVhillh the !est growthh told out11 of water anlld was scarcelvy attacked
    at all. Soakiig instead of floodingll appeared to result very belle-
    ficially. not oll1\ colli lrollill- ilnfustation bill inlducinl priiice growth of
    plalits it ,least pist the stlage' of stoolinig whell the coarse leaves oiler
    little ailtt'raction to the Vweevils.

    I I.IF (ITS OF I \IiI.Y. DlII.AY 1 1), AND ]\TI. 1 I.1)1 .

    Eice, ill differeiit fields thiat were firsWt floodel at various tiiies
    coveri'i" a seasolial ralgt' of dates ill accoidanclie with the planltingl
    ai d sprolutit i1g las ill dlie course' beell |oillud suilbjected to tlihe salme
    degreee of infestatioli. No advanlltage ca i he ailledk against the weevil
    ~y choosig 1ai pal 1tieiicular tillie for floodilig that will still be suilit-
    aleo for" tle leeds of lhie plants. All attemllpt to delayv full floodii',2
    Ibv a gradual soakinig of field, ill order that the ]plants light attain
    a strong growth and b)e a]le t wit stand or es ape attacks after
    deep wVater wVia applied miet with iinterferenc'e from hleav rainfalls
    Which flooded thle field-, anld lthe owliner tilien aved the water. The
    proballle effel'ctiveness of aolkilg is i dirated bl tle -a--e o f accidelital
    shortal e of Vwater 'is e nlietioielll il the prell'eolill" Ilbject.


    At, ('rowl ev, iLa., (ill Jtne 2S. illnpl)ection \Vi -s 1liade of a field of rice
    thliat halid been allowed to dry out fromii stoppage of water sulip)ply onl
    two occaV,,sions,. o1ne lastin-" six days anld tid e other four da\vs. Trie oc'-
    cliTrrelce of, larva wasV limited principally to the lllost heavily flooded
    partss. iiandl tlie roots of the lplalit were inot badly injured. Thlie 'com-
    Pparative \' carcit*y of thlie larva' throl g lhoult tlie field was attributed to
    theil fehcts, of thlie two intervals of dryigl" aiid tihe ricei escaped Iluch
    danll(ge froiii attacks .
    At AlIi vra. Ark., on August 1. other obsell''vatis werVe madllle on111 a
    field where s'carlcity of water 1 caulm'-d :all'erl:iat periods of dryilng.
    Water lhad beenl supplied but little lmore' tlial 1ll:f of' lthe liune >iiCe
    filst flIoodiing, oI1h the gr'oun li hladi beeu generally kept dapl with
    tlie' :iditioli of rainfall. No lar\' were fouilld ol thle root- of tlhis
    rice. alld 1llv a few weevil' s occurred 11 w';lIk plal ts loal8 tlihe ed'. ~
    of tile field. The' plainlt exhiibited Ia ligh. vioroulS. anlld fairly
    healthy growth. tih, e tlack of elltogl water l/aving evidently resultedl
    il a yellow tillge of thle leaves'. which, however', promised to be


    Till l: I S 1 \ VAT11- I \ li 17

    speedily vIvi- o111 (c 11fl r lin l, t lo llia ril'ain-. 'Im, 'In p tivall llltl\I
    pIrtoduced In xc'llnlt yil.l.

    I ld (M 1 I lH A J)\. 17.. > H 1 A II(IN Ml I I M I

    In ali e ixeil'iinent itL deti rinell ii heI r the 1>e ,4 furi li.d r- Iand
    app l n ii or ime woldh aer t ;l~:;i .v oli ",l hev bln t-l ;li tio plm,
    for -i, '.in',' rite iie pcepvI"lv I al (' I' a uccoll t rallying a inigll liii. s1it h lu -i vIt 1( III, IVt 14 tI 1 11 t ii I It[m

    i2 lll< c in|);i ttvi i l' l ii'r i eti \ al t- l i ; i> *It'- tin' a f- nl. i n- (*x;>it iiiiilt iitli
    on July S. T1Il' dIVlh ilv l \ :i-> llo lui|l a i-i l to ;I I( :In. d ptl ll
    of (; incl.t. lic T i t.> i ;>lln l" 1 Ical itn",ti of l11(ic pl.It- 1 1 l lI M
    of infestitaio lli' ouiitlin d as follw>":

    O r ... .i ,. )I ,,

    A<-iIl ll~i-rhnt h, is])!.....h s ; .. ............. .. ., . *|.i l . I -.

    ltH ,p r ta s I dl< . : d ,; ~ i ~ li~ 1 ... ] .... ... . .>'- *. -] ) ,1 !l .) iq l It ^.t ], i

    A. 1i'i/l l>!.< '( i| tii l l<' I) } :'ii r ti' "2 ]: ri c l l m t .' i l l. _~x i 'l /* r\
    Uil nl lt,:tl, l'>' l KI I.I- ] ,t'* ll --tl r .. '~a l ' ' I l li* ,*q ,, i [ ,- *** I .2 .. .

    TV~q l l |l] '')|' 1' ( i ll l l ri lt l'l[ 1 l flil t .iIIIi lll' nll' l.>' l';ll;r :
    For llii> lK It'r 1 (i li l / -- 1 l.- -- ll -- I T. < ir -" )ir l rr ii lYAi i ; l i--12.
    For 11 jl ]>low *2,' jw r Wrii i 0 00.n 1.1.
    M ".o Mtl e tiil is i lel :ni li".iiinsli ] it" .. OW(, P, J1'r (iiit 1 4 1it k'cs i.i tiii

    Crihlr ilciti: v'li ino ll'el'i- Ir t' anot 'oii Nva V oni t 10 A. a'i/ t "t i n'. thc lin'<1
    a r ati -'oii t l d t oIii l l ito- llll -I l : 1r\ ;r ( 'i ll,',' \ilt l 'l;i \ 1;6 i l l ,I
    inli h !d iiarea, o(f h(i i mnivii plt h. dlnl in trihv q qnl&iPlit !1 A lawi\"ii ,
    were tak li/ n lI t oo >ts of the siliarle li- ililcr o l' :ft;>ls.
    Too a d\*antsl i ni 11 41ictiicin, ol cla. rdin i,' inft-1:ii 1 It,, an. l i I,]
    shown A nir o A,,T tinh ;ippl ol<;ito oid -or-tiliz. ei' oir lini v .t' INla' A-il. loll
    rIllcr t i t cormalir le a ivndtare o icat(daI. It H". t rip "A, I t 1 ill, v do ,l<
    cl er ll i/.a t foio liiilim l moi libel a l'tc!. l Simi-P t 'in p liilo gih O\\vi ||l i h d
    lei pondcd in prq'ortlui n to tin' d r I ee i fm ilizalion. tn -l n1 I tiiiltt-
    Iiit, lva(*a^<. c(-.crpt hi 02i limied area, \\ lnri n, a NNI" W IN& Ozrnr ;.
    poorc.t g!row\tlh on accoint o4 she -(vverer pruniing, of ilm,.iia!ro

    Furdthe olwirvaliou,- iadi ;at MNidlaird. La.. Svcu Il Y, top tIn n-
    tclu-ii o (lia( fer-tilixvilion d~n"- iot, lrevvi.'io r I= M c ie liholer Owlr vr -
    p);islionl of Oa''r" loll tlin to overcoiiu zantm&k.



    The appearance of adults at arliticial lights at night has -,I 1i tl-ted
    thei plan it' placing lights ill the fields and trappings the weevils which
    ima\ 1)e attracted. Great numler.,rs of the weevils seek the electric lights
    (of stores il lthe townlis llhrmughout regions where the insects abound.
    ()rd(lia r lights in dwellings are somietiines frequented. At Crowley,
    La.. more than a i(hundred weevils have been collected within a few
    miiinites on a single store window. They appear most numerously
    on warm dark nights, but. like many oilither insects, they do not fly to
    li Ilhls in any (onsiderale numibler whenii thle moon shines. Neither
    dIc ls tie ime of their flight seem to last long, for as. soon as dark-
    tess has settled, most of them come in a rush. and only occasionally
    o stragglers- show themselves later in the nigh it. Their seasonal
    apllearance I., .71'ins from the 14t to the mi(ldle of April. and about the
    midilIle of August they become very scarce.
    Tests of the efliciencYv of light as a practical means of attraction
    were ('oltducted at (C'rowlev. A portable acetylene outllfit was used to
    furniish light, 1beinlg operated near rice fields 1 mile from town. Some
    of the best results were as follows, the weevils being taken on a
    cloth screen that was provided for the purpose of inducing them to
    alighit :
    On the niight of May v2(. l10. 2lr. Van I)ine started the light at
    O'clock and captured over -4) weevils in the first 15) minutes. Later
    tle lieeze increased and only stron- flying insects came to the li..hlt.
    Starting tle light at 8 o'lock oil July 19, after a day of heavy
    rains. Mr. 1hood collected 2 I w eevils in .15 initItes. Buht on the night
    of Jtlv i29. which was clear aind waril within slight south breeze, he
    placedI tlie light in the middle of a rice field and caught 125 weevils
    Between S and 9 o'clock.


    lOSO NINsNi, ADI.TI s.

    When tlhe weevils 4Iathher in particular p)ortions of a rice field, as
    they often do along dleeply flooded edges, dead furrows, and in spots,
    opottnitiies seemli to lie presented wherey the application of a food
    DOiiso0 oou 11 he a111:1(de (ffective. As tlie weevils indulge inll rather ex-
    tens-iv\e feeidilg col l)arel witli their size, tlie )poisolio g of tle
    plants would 1be alpt to cause lhe death (of great numil)ers of tlhe adults
    that tiiglit feed upllon the ploisoned leaves. The application of the
    lpoison shotldl be mtade utpol tliel first applearantce of the ins-ects x'fore
    ihev have had much chliance to oviposit. The poison must be selected
    with iteferience to its saftely von tle plants. and if in tlie forml of a
    powder, it could be easily distributed by means of a dust gun. from

    I1111' M IC \\'AI'I :" :IAVlL.

    which it iniht It> spread fi,r oe, l di-lance hY wvilnd. Prohally Ihe
    oil v il i -', r \vi'w ld lx" to live stock hain;; ac I" tthe wVatt theto
    (1li11.1. ,=: of which would he' a remote p,,sib lity.

    I VI I rNA M \NA(il No I.N I,

    (C lea ul 't ra l -" I,, -,,' i.* I in II Ifalini w ilh (lIe wcc, d :a- Iw\iv h
    oil ier c 4rop pes s i> advi>:le. lk>\' Is t n t' il;' iit' fTowtth 1)f tlhe
    various gira--es and (ollh'r pla, nts-. [)zrti'lcnlarl\ (, ,l))jcc( ioinalia ltc icd
    \;rieltv or rice. r w himh li u'rw ;lhonm a d! \villiin canakill. diklwli-. ;lnd
    water holes. nnnlih advanllaic co1l0 LIe thvrived tiowad (nt w milr-i>iji-.-,,
    of tihe of (Inilng tlf the \ ilk (om the ni dt, i\Alit('d low-1 p14 la w I )ra 1-
    agec of liai\()ii. shMnk', and waite Sivlc \\o)nld dwthtlli",--lit, olf --'rca:t
    Ihenitlt Aor ihe imr of (dthIe mivil atloe.
    l~e\'elii, of the "li rtifact ,ol lior lde Ilnal ari tI" w I, lanto h,1 i o, r N' o a d
    plowving,: it] suchi a man:1nler ais to avoid deald Inrr"ws a" inuch' o- p>o>-i-
    hlo MIMo l (\ial(' Inan\ l ll" th deiH'cSS "Kn w\ ln l(ion Ix'in^ Wdepy
    flooded conduce to a hiii Ah in f-lalit o fl (lhe ldifit" in Mirli lilac-.
    Finally, :a thowo nro h iiir'|);ralhi o fi( thic A^ l Ihd'or |)laitllnf k, 111 6
    recoImnint d," in ordlr tlhat rrat and wwcd^, mlay lo, eradicaed \\ i [i-l
    out (lit( inccc-'ily al deep iho dilig, for the1 pu p):ii']) olr d o ningr llicio
    This will permit \ory -hallow thlodingp \\itli \\,iiod- oi Ir iiriiL' tor
    mere soakiiin loelit olf ill(, r ps

    hic rice w vat er-w v dil t niw, in~ ov dani ali'c It li, wqK in lholl >
    Southerly Sta.itc- tlhan;iy olller i1 t-ccI afllcct'ilg, rme pllanti'. W hlen it
    is in the larval stage it roinn itl- ",vti' injuries to rive plants ly dr-
    stro\'in' ilhe roots. Some hlarei is dhoine lhY the aodllls in f'eedingl (in
    the leaves.
    I'lir inset ('l ieoses t'boo ltlauis t lilat g in weVt jl)a ^i and il
    hireds odlv Alilre it ll,- \at r. I""-'-IF F w arc evi tlv t% I (in on oo- ili
    wvail" or lmld. tinder \which condition- the l;iinr; hailrlich. A T r', o\\.
    and tiinsforii into |)ii]a' i and finally the adults n iii.i r ano!ii Mmoil i'p'C.
    Two :, ,, i ,l itlns linn lrossililv 1,h fpn cdl in a s ia>,n. Ilml ("m,
    gelint' ii n th t sv !.- to he tlih rule. .\Adnlts pas il( \vtwinter in liierna-
    tio alp earin-. in -loiir andl invwiii.- tlic th ic, Milkt-.
    The Il11ost praclical m ians of c" irll'Hin. t(he wmvil conl i-- in the
    clice ot"f draihi inini and! allowing inifwl' ,l rice liclM III drv Aifli-
    cienll < at the lp per t litle or eorl t lhe Mue a acks "f larv;i have ,ilv
    wveakle ed1 thI [ illant-. Alternate ll6 rdin, awl ,ryiL '. 11 'viin ,rrhd I oil
    p]rop rly. will aw omplis li ]1t e samet re-nl' t Ve sliallow (loivli ,,
    or -,. 'I ii.. of ichl1- re-train" inl estalt ion. ll'erlili/.zatii, a--i-1> 1lI
    ])lanlts to oVercolme injilry.


    Considerable numbers of weevils can be captured at lights and
    destcoyved, and the possibility of poisoning them in fields needs to be
    plt to the test. Cultural mainaaemenIt should be directed with the
    view e of enforcing every advantage against the weevil that will be
    ,nsistei t with the welfare of thIe crop.
    Approved :
    Seci')afry of Af/r'ti!,,nc.
    \AsaINGOTON, I). C.. Alpil 12, 19,12.

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