Vol. 15—1961 - NorthEastern Weed Science Society

391.
RUTGRASSCONTROLWlTR ATaAZINEANDEPTAM
l1f FIELD CORNIN 1960 1.
Jonas Vengris 2
Nutgrass (Cype~us esculentus L.) 1s a commonperennial weed in
MassachuDatts. In the Iastfew years this weed has been increasing and
has become one of the most noxious pests.
The objective of our tests was to determine the possibilities of
controlling nutgrasa with Atresine and EPTAMin field corn.
Procedure:
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The experiment wae conducted on a fl~e s~ndy loam ~~th fair draiDage.
The area had a good and uniform stand of nutgrass. A r&ndomized block
design with four replicates was used. Eeeh plot conaista~ of four field
corn rows 25 ft. long. All treatments were applied on May 31. Immediately
after applicetio~, EPTAMand the first thrae treatmenxs of Atrazlne (Table I)
were diske.d in 4-6 In. deep. Whenapplying the herb~cicle~, the 8011 was
moist and t,he next day 3/4 in. of rain fell. One is inclined to think that
soU-weather conditione for Atrazlne were excellent. OnJ1,UleI, Ohio M...15
silage corn was planted. To control annual weeds oucheck plots, the whole
exper.imental area was sp1l:'£I.yed 0'3 June 2 with 6 Ib/A of DNBP. A heavy wash­
ing rain occurred ouJune 15 and all plots ware cultivated with a t~actor
mounted cultivator en J'~e 17 to fill in gullies.
All herbicide rates presented in table I are expressed in pounds of
acid equivalent or active ingredient per acre.
Results and Discussion:
The effect of different treatments on nutgrass and corn was observed
during the entire zrowitlg season. Observations made four weeks and eight·
weeks aftar plan.~iug are recorded in Table I. Twomiddle totls of;"each
plot were harvested as silage corn on September 14. All herbicidea at all
appliad rates gave highly significant control of nutgras8. Somecorn
stuntina was observed with thet~ highest EPtAMrates but this did not
seem to affect yields. No significant differences between the three rates
of EPTAMwere observed. The action of EPtAMis rather rapid and our results
(Table I) indicate that weed control four weeks after planting was as good
as eight weeks after pla~t:ins. On the contra~ with Atrsziae, nutgr.asa
control on July 29 was much better than on July 1. Mixing applied Atrazine
with soil immediately after application did not increase DUtgrass control.
This probably was due to the heavy rain shortly after 'application of the
1. Contribution No. 1282 of the University of Massadhusetts~ College of
Agriculture. Experiment Station. Amherst. Massachusetts.
2. Assistant Professor of Agrono~. University of Massachusetts. Amherst.
Massachusetts.