Vol. 15—1961 - NorthEastern Weed Science Society

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,WEEDCONTROLIN ClaTAIN VlGBTABLECROPS,· 1960 '
W. H. Lachman~nd H. F. VerneU 2
'123.
This papel' .17eporte,"the 'results obtained Guring 1960 from field.screening
certain re~n~Lydevelop~G chemicals with, weed killing potentials. The plots
in all of these tests were located on a fertile Scarborough very fine, sandy
lOAm. While the land is we,ll draixuad, its high water holding capacity coupled
with ample r~infall seemed, to provide conditions that were ideal for killing
weeds with chemicals in 1960.
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Carrots
Plots were well prepared and seeded to Waltham Hicolor carrots on May 4,
1960. The weed killers used with their reapective rates of application are
listed in Table I. '
All treatments were replicated three times and with the exception of
Stoddard Solvent the chemicals were diluted with water and applied at the rate
of 50 gallons per acre. The weed population consisted mainly of lamb's quarters,
purslane, pigweed, galinBoga, smar~W8ed, and annual grasses. It,was qulte,~vident
that widh the exception of Dacthol the treatments were very effective ~n
controlling weeds. Considerable crop injury was apparent, however. by June 9
when plant injUry ratings -.ere recorded. Arating of "7" or bet,ter in weed, eentrol
and crop appearance is considered as necesaary to be acceptable commercially.
Of the 22 treatJUnt8 in the test only 4 met these requirements and
are listed as follows: 2pounda of B562, 2 pounds of KarsH, and 10 and 15 ,
pounds of Zytron. It was quite interesting to note that 100 gallons of Stoddard
Solvent appeJlred to cause some cropinjul.')' ,and also af~ect:ed )'1.elds', adversely' ..
in this tes,t. ' .
Lettuce
Pennlake lettuce was seeded 1n the plots on April 26 and the pre- and
post-emergence weed sprays were appl1edon April 28 and May 20 respectively.
aesults are presented in Table II. Here again it was evident tbat. the: treatments,
excepting Vegadex. were very effective ln promoting good ~ed control.
Crop damage. bowever. was particularly evident by June 1 and this effect was
also reflected in reduced yields.
Based on the tenet that weed control and crop appearance must rate 7 or
more without sacrificing crop yleld only the treatment involving 3 pounds of
Amiben met these requirements.
lContribution No. 1278. Massachusetts Agricultural E1pe~nt Station.
2profeasor and technical Assistant, respectively.