Vol. 15—1961 - NorthEastern Weed Science Society

ANNUALWEEDCONTROLIN POTATOESWITHDNBP, DALAPON,DACTHAL,
TRIErAZINE, ANDOTHEl1HERBICIDES·
M.F. Trevett, H.J. Murphy, and William Gardnerll
INTRODUCT ION
20).
This paper is a report on the effectiveness of the herbicides
listed in Table 1 on the control of annual broadleaf weeds in
potatoes.
Procedure
Katahdin potatoes were planted in a sandy loam soil the week
of May 30, 1960. Seed pieces were spaced 12 inches in rows 42
inches apart. Treatments were replicated six times in randomized
blocks of single-row plots paired with untreated plots. Sprays
were applied with one pass of a small plot sprayer at 40 pounds
pressure and 50 gallons per acre volume. Potatoes were hilled
three times. The final hill was 24 inches wide at the base, ten
incheS' high, and six inches wide at the top.
The principal broadleaf weeds were: Wild Rutabaga (Brassica
rapa L.); Red-root pigweed (Amaranthus retroflexus L.); and Lambsquarters
(Chenopodium album L.). The annual grasses, Barnyard
-- grass (EchInochloa crusgalli L.) and Foxtail (Setaria viridis L.),
were not present In SUfficient quantity to permit accurate evaluation
of control. Weed counts were made 10 weeks after planting.
Results
A. Comparisons of DNBP-DALAPON Mixtures with
Mixtures
DACTHAL-TRIETAZINE
Data obtained in 1959 (1) indicated that mlxturesof Decthal
and Trietazine might result in better total annual weed control
than either herbicide alone, 'since Dacthal "where Brassica species
are present, need reinforcement with a predom1nantl~broadleaf
herbicide~ and "Trietazine needs reinforcementwlth a gr-amdnLc Lde ;"
Data obtained 10'1959 further indicated that mixtures of Dacthal
and Trietazine might result in a longer period of residual weed
control than the currently recommended DNBP-DALAPONmixture.
Data in Tables 2 and 3 show that none of the other treatments
produced statistically higher yields than the standard treatment
of 3 pounds DNBPplus 2.22 pounds Dalapon per acre.
11 Associate Agronomists, and Technical Assistant, respectively,
Agronomy Department, Maine Agricultural Experiment Station,
University ot Maine, Orono, Maine.