Vol. 15—1961 - NorthEastern Weed Science Society

98.
Table IV
Weed. Count& FolloWing Second Application*
Treatments ,
Purslane Smartweed Barnyard Other
'
Grass Broadleaves
Randox T 6 qts per A 5.9 12.0 8.1 1.0
9 2~? 12.0 5.7 .5
12 l.~ 4.0 4.5 .4
Randox T 42 Ibs per A 4. 30.0 6.4 .7
II u II
franules 63 . 1.1 8.0 3.3 .3
II II u
35~) 8~ 1.1 4.0 1.8 0.0
Randox
gr-anu Lee (?O%)30 Ibs per A 4.9 32.0 6.2 4.1
u II U
Randdx ' '6 9.0 58.0 11.2 6.9
spray··
untreated control 58.2 87.0 57.8 24.1
* average n~ber of weeds of 3 test sites based on weed counts
, per 23 sq.tt.
** lambs quarters
pigweed
'Ragweed
Randox is being used e~t~nsively on,on10ns but has not given adequate
control of smartweed In,severely infested a~eas. This 113
due in part to the prQpertles of CI:>AA,but~lSO 1s due t(\ the delayed
treatment after seed,ing ·which means at, least some, of the smartweed
has emerged and·is no 10ngerSu8cept1ble to CDAA. Control 1s
usually ·1n the range of 50, to 6~ .and ,is borne out in the above
results. :By virtue, of its increased s1ll8rtweed activity in the
Midwest, it was felt that Randox~would serve asa goodsubstitute
for growers having a smartweed problem. The results did not
confirm this for the pre-emergence application for a yet undetermined
1"eason. However,smartweed cont1"ol was SUbstantially enhancedwith
the use of Randox T as compared to Randox following
the second application. Randox T at the intermediate application
rate ga~e~5, to 90%control while control with Randox controlled
30 to 60%of' the smartweed. The active CDAAeqUivalent at these
conoentrations for Randox T and Randox is 6.3 and 6.0 lbs. per
acre. It can therefore be assumed that the trichlorobenzyl chloride
accounted for the increased smartweed aotivity.