Vol. 15—1961 - NorthEastern Weed Science Society

effective a8'1n1959 (1). This could possibly be due to the relatively
long interval between .eedbed preparation and material application. Weed
seedlings in evidence at the time of the Randox applications were not
controlled. Once more, the 1960 tests showed that it is sound practice to
apply DNBPat emergence or immediately after the emergence of field corn.
EPTAMgave excellent control of grassy weeds but broadleaved weed control
was significantly poorer. In general, the best annual .weedcontr~l in our
field tests was obtained by triazine treatments. Wedid not get significant
differences between rates, time of application or form of material (Atrazine
or Simazine). This is probably due to the satisfactory soil moisture
i
conditions throughout the growing season. Mixing Atrazine and Simazine with
the 80il immediately after application did not increase their effectiVJ!l,ness.
One is inclined to postulate that under dry soil conditions mixing should .
provide better weed control. Cpd. B, as well as Fenac, performed wallin.t
controlling annual weeds but both herbicides caused injury to corn, especially
at the 4 Ib/A rate.
Summaryand Conclusions:
1. A weed control experiment witb field corn was conducted on a fine
sandy loam soil. Hine different herbicides at various rates and times of
application were used. Corn was planted on moist soU and within a week
following the application of pre-emergence treatment, about one inch of
rain fell. The weed population consisted of: lambs quarters. old witch
sra •• , barnyard grass, pigweed, crabgrass And carpet-weed.
2. All chemicals were effective in contTolling broadleaved weeds.
With the exception of 2,4-D, 1/2 Ib/A post-emergence application, all
herbicides effectively controlled grassy weeds also. The best weed control
was obtained with Atrazine and Simazine. UndeT the soil moisture conditions
which prevailed as little as one Ib/A of Atrazine ~r Simazine gave good
annual weed control in field corn. Applying triazines before planting and'
immediately mixing 4-5 in. deep with the so~J .lIlas not superior to the
pre-emergence applications. Feuac and ('pd. 'B'gava a very good weed control
but corn injury was significant. EPTAM4 l~'A and 6 lb/Arates stunted
corn for six weeks. Later on the, corn regained uormal appearance and
yields were significantly higher than the checks.
Referencee:
1. Vengris, Jonas. Weed Control in Field Corn. Proceedings 14th
Annual HEWCC,pp. 367-369. 1960.