Vol. 15—1961 - NorthEastern Weed Science Society

130.
Jvaluation of Several Pre-plant Herbicides for Petunias
Chiko Haramaki l
One of the largest expenses in growing outdoor aDmlal flowering plants
for either cut flowers or display pur.poses has been the coat of weeding.
After the display plants are transplarlted. the weeds soon outgrow and in
many cases stunt· the plants. The most commonmethad of weed control in
these beds has been band weeding, but the use of pr~-plant herbicides has
been practiced to 'some extent. The purpose of this experiment has been to
evaluate several pre-plant herbicides for ef.fective weed control and also
to determine how so01.'1annual flowering plants could be. planted after soil
treatment.
Materials
and Methods
The soil in theexper1mental area was Hagerstown silt loam. The
soil was roto-tilled' several times to a depth of 5 to 6 inches prior to
treatment. The plots used were 100 square feet in area. All the preplant
herbicides used were applied at three different concenrtrations
plus a check, .and replicated three times in a split plot' design:
The herbicides
used:
Enc (Sta.uff~) - 6 pound/gallon concentrate was applied at the
rates of 5, 10 8nd 20 pounds of active material· per acre.
'1'heconcem:rate was mixed with a sufficient amount of
water to make a gallon of mixture, which was sprinkled
on each plot.
Vapam (Stauffer)-was applied at the rates of 1/2. 1 and ,2
quarts per 100 square feet. It was mixed with water and
tben a gallon of the mixture was sprinkled on the plot.
My10ne (Miller) - a 25~5% formulation was used. It was applied
at the rates of 1/2, 1 and 2 pounds of active ingredient
per 100 square feet. This ~terial was hand-broadcasted
on the plots. .', .
5996 (Niagara) - a 25%wettSble powder was applied at the rates
of 1., 2..and 4 pounds of activeingr~dirent pe.r acre. A
gallon' of·ea.'ch fJoiuticm va, spr'inl4ed on each plot.
'.~., ".
EP-161 (Morton) - a 20% emulsion was applied at the rates of 1/4,
1/2 and~.l quart per lob square feet (43, 87 and 114 pO\lnds
of the active ingredient per acre). Forty-two milliliters
of emulsifier was &ddect'for eaQh quart of EP-161 used. The
ma~ia1s were mixed with water and one gallon of the mix­
.tuxe was sprinkled on each plot.,
lAssistant Professor of Ornamental Horticulture, College ,of Agriculture,
The Pennsylvania State University, university Park, PeDDSylvania.