Vol. 15—1961 - NorthEastern Weed Science Society

366.
fiE USE OF FENACFOR QUACKGRASS (AGROPYRON REPENS) CONTROLIN CORN: --'
PLOW, FIT, PLANTAND'1'RE~-'
Stanford N. Fertig 11
(A Summary-Report)
INTRODUCTION:
..
An increasingly serious weed problem on New York farms is annual and
perennial grasses. With the use of selective herbicides to control brosdleaved
species and the reduced use of cultural practices, the grass problem
has gradually increased and is presently the most competitive problem on
many farms. This is particularly true o.f queckgr-asa (Agropyron repens).
Several new chemicals' have shown promise for quackgrass control in
corn. Some of these compounds shaw promise for seasonal control, while
others actually eliminate or markedly reduce the stand of quackgraSs.
EXPERIMENTALMm'BOD.ANDPROCEDURE:
The objective of this particular study was to investigate the effec·
tiveness of Fenac (ACP M.673·A) for quackgrass control in corn when applied
at low rates as pre- or early post-emergence treatments.
The experimental design was a randomized. block with four replications
of each treatment. .
The experimental area was plowed, fitted and planted to corn on May
20, 1959. The Fenac at rates of 2,3,4 and 6 pounds actual per acre were
applied at four dates after planting as follows'
A. Immediately after planting
B. 3 days after planting
C. 6 days after planting
D 9 days after planting
The plots were not cultivated during the groWing season.
RESULTSANDDISCUSSION:
The dates of application and the rates of chemical used (Table 1)
showed no retarding effect on corn emergence or on plant population. Bowever
1 the development of the corn plants was affected by the 6-pound rate
applied immediately after planting and by the 4· and 6·pound rates applied
9 days after planting. The treatments applied 9 days after planting were
post-emergenoe to the corn. At these higher rates, the diameter of the
stalk and the leaf area were visibly reduced. Based on measurements during
the growing season, the height of' the corn was not affected by any of the
rates of chemical used.
!I Professor of Agronomy, Cornell University, Ithaca, New York.