Vol. 15—1961 - NorthEastern Weed Science Society

300.
Control of seedling weed grasses at the recommended rate of
30 lb/A was effected for a period of 120 to 140 days. It was
possible, however, to seed turf grasses successfully 86 days after
treatment.
tested -­
There
even at
was no.
greatly
damage to
elevated
any ot
rates.
the established turfs
Diphenatrile is an extremely sate material. It has an acute
oral LDSO in mice of greater than .3$00 mg/kg. It has not caused
dermal irritation and possesses no unpleasant odor. The remarkable
selectivity against seedling grasses and safety to ornamental plants
(Table 3) makes it possible to use the material as a seedling grass
herbicide in flower beds, as well as ·in shrubbery plantings and
broadleat ground cover.
Table 3. Response of Weed Grasses, Turf Grasses, and
Ornamentals to Diphenatrile
--- .... ------ .....------- ..... _--------------
Susceptible
I Resistant Resistant
_--------- I I
Grasses Turf Grasses Ornamentals
~_ ......
i
Crabgrass, small I Bluegrasses I Annual flowers
Crabgrass, large BerIl1uda I
I
Evergreen shrubs
Foxtail, yellow I Bentgrasses I Broadleaf shrubs
Foxtail, green
Centipede I
I
Myrtle & Ivy
Goosegrass Fescues , Roses
Sandbur.
I
St. AugustilJ.e t Chrysanthemum
I.
Turfgrass seedltngs
Zoysia I Ornamental bulbs
j. _.J.. . . ..... .
I
I...
I
-.- ....------------------------- ... -
Dinitroaniline
Results
Study of the general herpicidal activity of a series of unsubstituted
dinitroanilines revealed that the 2,6 dinitro compound
was markedly more active than the 2,4 dinitro, Which was, in turn,
mor-s active than the 2 ,3 dinitroaniline. When dialkyl substitutions
are made on the amino group of the 2,6 dinitro molecule, the resultant
compounds lose general herbicidal properties, but become
highly selective against seedling grasses in pre-emergence
applications. Thedi~n-propyl has proved to be the most active
dialkyl substitution.· ,ActiVity can be further increased by apJ'.'&'Oprlate
substitutionsia the 4-position of the ring. The herbicidal
order of activity o~ the 4..position·substituents has been determined
as CFj> CH 3
) cas H. The4 ..CF 3
(L-36·3'2) has been given the