Vol. 16—1962 - NorthEastern Weed Science Society

1) Ansar A-12 at 2 Ib + WAand 4 Ib and Methar 80 controlled significantly
with only one application but injured the basic grasses severely.
2) These chemical treatments - Ansar A-12 at 2 lb, Ansar A-35 at 3 1/2
lb, 3 1/2 Ib + WA,5 lb, Super Crab-E-Rad and Super Methar all controlled over
90 percent of the crabgrass after two applications. These treatments caused
'i++_'~ +n mnnC'T'::a+c +OI"nn.I"'\"'~""''\t .; ... .;1........ +1"\ +h"'- ............"'"' ... 4 ... 1 _ ....... ~ ....,..
The liquid materials for bothp%e~ and post-eme~nce trials were applied
with a 2 gallon pumpsprayer at 30 IDS pressure arxl.'volume of about 250
gallons per acre. The dry chemicals were applied with a calibrated spreader
set according to labeled directions or by mixing weighed amounts with dry sand
and broadcasting by hand. 1:
Results
Tables I and II relate the chemicals, rates of application, number ofap.
plications, average plant counts per square foot, percent cover of crabgrass,
injury readings and percent control of· each treatment!~er the check.
Pre-emergence
531
Whenworking with living organisms one can rarely expect perfection or
exact resul t s, It is pleasing to note that fifteen df·'the 44 chemical treat- .
ments resulted in l~ control ofc1'lIibgrass. These themical treatments are
as f011011SI Trifluralin at 2, 4 and· 6 lb; Dipropalinl'at 8 lb; Dacthal G-l~5
at 10 lb; Rid (Dacthal W-50) at 9.8 lb; Vitogrow (Dacthal W-50) at 10 Ib;
Agrico's Diphenatrile on fertilizer; Purge (Tricalciuilfarsenate 355 Ib); Nlill
(Diphenatrile at 30 Ib); DOlI's crabgrass killer (Zytronat 15 Ib) and finally
Corenco 106 (Diphenatrile & DSMA31 and 5.4 Ib}, . '-~
There were also four chemical treatments with over 90%control, namely:
Dipropalin at 4 lb, Diphenatrile at 30 lb, PEWCF-l08 at 47 lb and Trifluralin
E.C. at 4 lb.
Somematerials which gave 90 - 100 percent contrbl also discolored se-.
verely. They were Trifluralin at 4 and 6 lb, Dacthal.G-l.5 at 15 Ib and
Zytron. Most of the chemicals that reSUlted in onlyY~ir control showed
little phytotoxicity to the turfgrasses.
It was noted that some of the chemical treatments, Niagara 6370, Bandane
atta. at 10 Ib, Bandane Verm. at 10 Ib, Halts F-2b, NoCrab, SO 6623 at 6 Ib and
Dipropalin E.C. at 4 Ib had a higher crabgrass count than the check plots.
There may be many factors involved here. Twowhich stand out are that the infestation
of crabgrass was not heavy enough to canceFexperimental variatiOn
due to crabgrass stand or possibly because treatments,r'lctually created a m~±,e
favorable condition for germination and growth of cra~rass plants.
Post-emergence
Again in this test it was encouraging to find that fifteen of the treatments
controlled over 90 percent of the crabgrass. Within this range of control
there were other interesting reSUlts, mainly:
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