Vol. 16—1962 - NorthEastern Weed Science Society

294
;~~~r::~~~~r::::~~::U:~l~
:~;~!~~0~h~::Oin~::1::jf~~'!:::~·:0·;e;a~~it'~
fall an~ held ~on~~ant., tUlthe. {o1.~Cl'(l~._epr~Df!I'~~'~ .o~ the reduct1~ ;0.£
rbi .. e. by 'e.c,thefructose1tifcl ;ehOvel al\ iutl:'tl1. etecl1ne of 37 per Q~~,
WhiCh'increa,"'. ['loW.ltlto 53. p.'~..,by ..•. late .au.~UIIIIl .."•. a:::III.~_.. 'tb. en.-decre.s.•.ed 'to.···. 7+9'-"
per cent by the nell;t sprln8 •., _ D~'iijieiiiAoW.dno •• ~~~ioJ1 the.f~lICt,~
yle1dl, but call1.ed .·a fa1rly~~lcf'''.c;,~~e 4~rJ.bI :~~~: .~~ to 72 per cent in
total carbohydrate.. The effeelt ofDlftlapon· cleona"iI~.HDI the fall and winter,
re.u1ting In a reductlon of only ~t~r:: cent· by Maylo-;-I96·0.
Interactlon beeweett cU1tunf.q~cah~~~' t'l'eaitm~Q~:: ;\~, r
, ' . -, I .. ~".
There wae no liplflcant tRt..... loa between the-.ffectl of cultural treatmenta
and herblcldal apPUca!:i~i-~if~. auivlval ot~ltb.ea ,unUlthe ~a~t, ~YCl~ :
.~~inl date,. : . . '. '." ";,: .i : '.", ,)c'" '"
~ ..~
'k explanation of the il1t:eracf'ioou1' be given by cOlllparing the effecta of
the different herbi~idel witl" -eac~~¥~ra1tr.•at~~t..,,~.~ fi~a1 1aq>~i~J d~t. ,
given ln Table V. "rhe IDOltl:tti~\\1 c~ari.~ 1,."".r ....:jlo cu1~lvat1on wal
app1:ted. The hllgh_it rhllom."yl'e1.d "a~ not .obta1~e4~ 'the untreated .od, but
from p10tl trea/:ed with Dalapon or r,-l!. Thouih tlM:£i~ferencel are not lipificant,
they do indlcate th,atth'~~n~.rbicicle.~l•• ti~ .ffe,c~I,~, 1~,
de. truftion of quae:fcgra.. rbisc.d' unl •• ~: accompaz:ilad bl'; ~111.g. treatments, even
thoupr topgrowth wal killed and'regrow'tfl .uppre .... ltl;_apon.At the oppollte
extreme wa. Atradne, which actually !~.'\llt~d in lei.' rhizomes .urvivlng when
applied to uncu~tivated p10ta than,~ell lupp1 ... n~!d~y_plowl~orfa.l1ow •• "
Quackp'''''aocf·'~i'eat'd'W'1th Atrli.til~ alia18ft uncl~'tii~"'4 Ihowed a 9~ per' ceilt·
reduction ln the rhlzome infe.tation by' the followiiii".pHng. . .'
AcCllllpar1'''b of-the"h.rbldd •• *thtrf the plent' tr.. tJ.erit indicate •. tfi~i 1.11
herblcidel l~t.a~:highlyd.. Y'eantreduct!on~ ~rhill'Ollle yie1d- ""","
compared to .pring p1OWingwith-:nci:Ji.i&+cf.d-~ -Thi.,:_~.p.rtdue to •• ~~u1ati,
influence of plowing on tat! su~~equet:lt ~0trt:li o~,tuac~t.... rhlZOIile.'
wheillto herbicl.e w••• pplied,·lhowiq'art inctea.e'-o~~t 50 per cent by May 10,
1960 over that ~f the uncult-tvat_::tIIaeeIt-plota •. The r.sults of continuous f.llow
tended 'to elimi'.te or ma.k the .he~~eI4d eff~cu.ll"~J... ther uniform,anej ."
complete de.tru •.ti~ of quackF".j'lrh1&~e. ; '...•.. Th
e ·~t•.~~:- tbat, by th!! follOWing
rprlng,
69 per cent
the, fallow traatllllllta-r48U.ii'd.
whe. no herbicide was udll.to
in rhi8'" ruction ranging from
81. per cent' when Atredne was applied,
compared to theuntr::eated Qheck)t~t:.;:H:There wereDO-.~f,Uicant
be tween, any of the fa llow treat\!Jetit!.; ", ,:. . "" . .'
d1ffere~c.,
.. .. ,.
,
I : ,.:, ,", .', , ; , J.,'_ .....!' - . ~'0:[:-'~ .
The lntera4tion between cultural' alid"chemic.1 tre.m.nts on the tou1
fructo.e yield "al .ignif1ca~t a.t .1J.-.am.pl1ngd.tea.-'~'leaeral ..' any c;om~~.­
tionl of treatment.lthat resu1.~~~o~'.:~.n.ein t~~~d of'qu.ckgrssl rhlzome.
simu1'uneoualy causH a change"!ll th.t.fOod i ••• rv.·· . "t·of the rhlllom.1 in the
same direction. Conl.quently., tha.~enc:.-of the tieatmente on the totd
fructole yield "as ~sually accent""tea-;; Table.V1 'i?""~,lUIIDAryof thein~~~
act~on data frOll th~ firat, la,f~ tft1, ;~d t,lna! .""'UIlI'ietatel. - .\-
. . .'
.\..,. _.~,._., ...,....
All treatlllllntl wlth the exceptiOQa ,of, !JllculUvatR plot. treated w1!:~ ,".,
Da1apon or renae relu1ted in high1y's1snificant carbohy4rate yield reductiona by
the first salDl)Una date'. The aillll:1e u1owinll: treatment eaull/ld the ftr ..d"",ifta,,"