Vol. 16—1962 - NorthEastern Weed Science Society

316
NUTGRASS~LIN rtELD CORN1
R. H. Cole.. ,C. D. _le~~end P... B-.Spdnger, Jr. 2
. The objective of the .. lm.tigatlon.1ru to determine the
rate ofappl~cation ofAt~~ioe (2-chloro·4-ethylamino-6­
isopropylamlno"l-trlazine)iaftd EPTC(ethylJ; N-di-n-propyl- .'
thiolcarbamate) needed to control yellow nutgrals (Cyperus
esculentus L.) in field corn. Comparisons were made between
pre-emergence and post-emergance application. of Atrazine and
liquid and granular application. of both herbicides.
Nutgrass control result. with Atrazine and EPTChe".
previously been reported by Vengris (2, 3). The effect of the.e
herbicide. on corn and nutgra •• plants hal been investigated by
Donnalley and Rahn (1).
Procedure
Two nutgrass control test. were conducted in 1961 at the
University Substation Farm, Georgetown, Delaware, on a deep,
well drained Norfolk sandy loam. In Test I a heavy rye-vetch
cover was plowed down two weeks prior to planting and in Test
II a rye cover was plowed down one month prior to planting.
Fertilizers were used as indicated by soil tests to approximate
yields of 100 bushels per acre. The plot size in Test I was
12 feet by 60 feet and in Test II, 12 feet by 30 feet. Hybrids
with known performance were planted on the dates indicated in
Table 1.
Applications of pre-emergence treatments followed planting.
Post-emergence treatments of Atrazine were made approximately
three weeks following planting. Wettable powders and emulsifiable
concentrates were applied in water with a bicycle sprayer.
Granu1ars were applied with a hand shaker. EPTCwas incorporated
with a hand rake directly following application. The rainfall
1. Published as Misc. Paper No. 410. Contribution from the
Department of Agronomywith the approval of the Director of
the Agricultural Experiment Station, University of Delaware,
Newark, Delaware.
2. Assistant Professor, Research Fellow and Assistant Agronomist,
respectively, University of Delaware. Mr. Springer is
presently Technical Advisor, Central Chemical Corporation,
Hagerstown, Maryland.