Vol. 15—1961 - NorthEastern Weed Science Society

Resulta
All treated plota were clean of aDDUalweede in April and remained 80
UDtil about the fir8t of June when weeda began to appear In the p10ta treated
with propaaiu 2 lb. and 81mazine 2 lb. About the lliddle of June, BuOIlJlll!UI
tbat'eeceived 'atraal. at 4 Ib./A began to .bow injur,.
Table 1 ahowl the weed control aad plant injur, observed at the end of
June ancJ early July. B, tbis tiM, w.eds bad bacun to Brow in the plotl
treated. witb propazi. 2 lb. ancJlf.maalne2 lb. Plota tbat received atrazine
2 lb. or 4 lb. ancJ 11mazine 4 lb. were stUl relativoly clean. Baaed on the
aUlllber of planta dead or injured. Rhododendron could not tolerate atraal~e.at
4 10,. Dut other' treat1Hnt1 were .afe. Simaaine at 2 lb. wal the oa1, 'treat­
_t that did not' injure Iuonymua. ' .
. .
......•........•.....•.••.•••...•.........••...•.. , .
- ~
TABLE1. WEEDCONTROLANDPLANTINJURYJUNE 27. 1960 '.
. PROM.APPLICATIONMADE' OCTOBER23.' 1960.
CRBMlCAt RATE AVERAGB RHODODBtmRON. EUONYMUS• ....
(lb./A) WOD CONTROL (No.out of 12 planta) DJURY
.­ BATING*
DJW)
INJURED (Ju1, 8,1960)
Check
1
0
1
.None
Propazine .. 2 5
0
0
Slight
Atraz1_ ,2 8.3
I
I
Moderate
Atraz1ne 4 8.7 4 3 Severe
Simazine 2 4.3 1 0 Rone
stmaairae 4 9 0 0 Sligbt
... - -
*Weed Control
,
Retinas:
1 : no control;
"
9 : clean
; ~;~,.
This and other trials baveshown that a fall application of ·.tmazia. at
2 lb./A gave practical control of annual weede untn about the firat of JuDe.
when crabgrass was u8ual1, the firat weed to appear.
FJ:.'OIIl this teat, ··it 'appeared that EuOU'!!8 radicans ve,etus va. quite
sensitive, to the triaz1nes. Atraztne was more injurious than limadaa.
The symptom of injur, to Buonymus was chlorotic leaves Dear: the ends of
the br4DCbes. In severe cases the _plants were atUDted.. _
\ . .' , ' . ~ '"~ ~ ,
QU'ACKGllASS IN BsTABLISHBDNURSEllY STOCK
All teat. were conducted at a coaaercial aurler, onaandy 10.. soU.
l!.!! Applieation-!!! Tr1a~inel. ' • . ,-,
t s
All applicatiOUs iie~e 'aprays of wettable powder fOl'1llUlatious in about
50 gall0DS of water per acre. St.. a1ne 5 Ib./A and atrazine S Ib./A were
applied September 23, 1959 to quackgra88 in established Globe Arborvitae.
Hemlock, and Taxus. Quack sprouted and began to grow in April, yellowed
and began dyiag back ta May. and did not re-.proutafter cultivation. }alots
appeared to be clean of quack in .June and for the remainder of the aealon.
The nursery pluts did DOt abow anJ lymptofDSof injury.