Vol. 15—1961 - NorthEastern Weed Science Society

392.
herbicides. In senerel."we.had,a rAther rainy apri.na and summer in
Massachusetta. Plots treated with 4~razinewer8 free from annual broadleaved
as well 8S grassy weeds' throUghout the growio.s season. Plots treated
with EPTAMbecame infested with,p~ed (Amar~thus retroflexus) during
late .eason. It is pos.ible that excessive rain shortly after application
of the herbicide decre~se~~ itd ,~ffectiveness, '~y"r ~ellent broadleaved
Weed control wasobta:lned. ,wit!.) 4 Ib/A and 6 Ib/A of EPTAMin field,
corn' (1). " ....
Beca~se of g60d nutgr~s.co~~rol by 1111herbl~ide8 and at &.11,rates
appliecl, ylel~s .9f silage co.rD.werealgD,if1cautly increased •. No 81pificlUlt
differences were noted between herbicides or rates applied.
On the basia ot~one ,·year's resulte it wf'luld appear that 801'1dnuta r aSB
eontro~ ca~ be hll.d ~~,ora 4 Ib/ A t')f AtruiDe or EPTAM. Atr"zi~ ,fJJ sligbtly
more effective and .does 'QOt,.4f..fect. cornplauts. .
Summa!'Yand Conclu'iona:"
. ,;;,'
1~' ~ year'. field ta.stA':1Ddicate tb.Jt Atrazlno 1s ~ffect:tve and
promisine in co~rol~ina nutgrasB (Cyperus esculentus}.A rate of about
4 Ib/A is suggeste.d.' Applicatit9nssbould be made in the sprinS ~Late1Y
before the, plantina,~f~~or:n~ "'M1Jd.q appU.ed berbicide with .soil to a depth
of 4-6 in.~ 1s .dvent&seo~&aspecl&lly 1£ dQt weather and soil cOliditittnB are
anticipated. Atrazine can be applied atp14nting ~r &s a pr~~emergence
treatment f&rcol:1.'i.· ,,
? "EPTAMi' a.~so. p;;,omif;lng f,.r controlling Qutgrass in fielA col"Dt' '
Sugge~t'ed rates Are 4-5' Ib/A •. This chamic.g.t should be applied before plsD t1 ng
and tmmediately inc~rp~r~ted 4-6 in. deep in soil by disking. For ·tw~ caMe-Cutive
years anme Cflru stunting reaulted from 4 Ib/A.of E~ (1) but later ~D
plants reg4tae.d nfixmal appearance and yieldAwere oipifiC411tly better tb#n
checks.
Reference:
1. J. Venitt •• Weed.Control in Field Corn. Proe.14th An.NEWCC.367-69.1960.
tABLEI. Nutara,s Control
, .~l!~!.ve Values.
in rield
Check -
Corn
"102
Corn
. Trea~ents Yields
1. Check ..... ,
2. EPT~ 4 lb/ A." pre~pl.". disked ' in
3. 'EPTAM 6 lbJ A) pre-pI., tUsked. in
4. ,EPTAMalb/A. ,p:t:e-pl~ ,disked in
5~ At;,zine 2 lbJA) pre-pl., diaked
6. Atr~zine 4 ib/A. pre-pl., disked
7. ,Atraz~ne 8lb/A, ~pre,;"pl.{, dll.ked
8. Atrazine ,2 lb/A, .pre-pl. '.
9. Atrazine 4 lb/A, pre-pl.
10. Atrazine 8 Ib/A. pre-pl.
" L, ~,. D' at 5% level
t.S.D. at 1% leyel
___
10·
------..:1=5------XLin
in
in, .
8
.__
100
1~1
131
128
U3
133
131
124
124
136
17
23
--=::::.