Vol. 16—1962 - NorthEastern Weed Science Society

267
Table 2. Eftect Of'herbicidet~el[Ltments on plantv1go.r and weed control,;
;r~a;~n; - -vI;i· -W~ed. ~o~t;'i'o~;o~ ~~s~~c;~bIcId~:~lIed. - -
J~e 14, OCtober 24" .. '- - - - -'- __ .~:~ - - - -- - - - --:
_____ ..._ ~... 1261._ ..._ ...§.iH!&!:!,a
_
(Mean ~)c (Mean j)C
e_ ....KF!i,! _ Qt!!e!
1
2
3
4
5
6
7
8
9
16 de 20 c
45 bed
, 6e
70 ab
15 c
35 cd 42 bc
78ab 71 ab
81 a 74 ab
60 abc 76 ab
71 ab 76 ab
51 abc 88a
1.5
3·0
3·0
1.5
3·5
3·0
1.5
3·5
4.0
13',0
1~;0
12.0
8.0
8,0
'110.0
/1_":.
12.0-Eptam
6.0-Casoron
8.0-Dinoben
24;0-Dacthal
------~--_._----~~'~------,-~~---------~
aExpressedas Percentage of t1u,lmo~t vigorous hoed~c1leck plots (rated as ~).
bA weed-free plot would be given a 10C/f.rating and, a complete weed cover l[L CJ1,
rating.
'
CAverage ot four replications .~e~s in a;;olumn19tl1 the same letter do not
differ s1sn1fican,tly at, the 'fIi.., ieve1 of probab" 'F!Y' The percenta ges",lIere
transformed to, angles (angle. =arcsin percen } before ma.k1ng .
statistical analysis since theve.riable cor..J:l,sta of the proportion of "
individual plots s:rfectedwhe~'the distributioJ1,tends to be binomial'u
force. " .
. '.{.I
The vigor of plants in Trea~nt 8 (the' fO:l;'lller,'lIhQedcheck" which
received only'o11,e application of S$mazine and ~rs.U.) "id not differ
significantly froID plants in Treatiments 5, 6, 70Z'~9 which received
greater quantities of herbicid.e.,·Only plantsin~tment3 (Casoron
alone) and '!'rea_ntl (the fOrmer non-hoed checkf:,.,re significantly
poorer in vigor than most of the ,t:rea~d plants,
. ", ;
Plants in Treatment 4 (in whicJa a total of 12 ·pp~ds of Karsil plus. 3
pounds of Simazine were applied) were lower in vigor than Treatments 5, ,6,
and 8. Many of the plants in Treatment 4 had both chlorotic and necrotic
areas on leaves. The leaves were often "tattered" in appearance since
portions of the hecrotic tissues were broken off.
The vigor of plants in the "check" subplot (with reference to September
and November treatments) did not differ significantly from each other. The
stand in Treatments 3 and lwa, "pc:lOrerthan in all.,other treatments.
,j, .
Interve!nal and marginal chlorosis 1 presumably,Q,ue to higher, levels of
Simazine, was observed in Treatments 6 and 9 where a 2-pound application was
made on September 29, 1960. No .chlorosis was detec~edin Treatments 2, 4, 7
or 8 where only a 1.5-pound appUcation was made Onj-WOVember 4, 1960. All