Vol. 15—1961 - NorthEastern Weed Science Society

145.
Conclusions
ADexperiment carried two years gave certain indications of the
influence of granular herbicides in the lining-out bed on five species
of woody ornamentals. Of the five species, Taxus and Juniperus appeared
to tolerate all chemicals at all rates used. Considering herbicides used
two full seasons from the time of setting: Kalmia appeared to tolerate
CIPC, CDEC,and Simazine; Rhododendron appeared to tolerate CIPC and
Simazine; Azalea tolerated CIPe only.
Granular 81maztne and atrazine at land 2 pounds per acre gave
effective weed control, and liner size plants of several species apparently
could tolerate those rates. The use of 1 or 1 1/2 pounds per acre of these
herbicides would seem to be especially worthy of further trials.
Because of itl apparent safety to a wide range of plantl, CIPe
would appear to be a useful herbicide for plants that are sensitive to
the tr iaaines.
GE'NEBAL REMARKS
The work reported here included herbicide trials in the lining-out
bed aDd in field-grown nursery stock. S1mazine and 8trazine were promising
for both bed and field. Wettable powder and granular forms were used.
Simazine and atrazine gave similar results in all tests reported
except one. In this one test, which involved fall applications for control
of annual weeds in Rhododeodron aDd Euonymus, atrazine gave longer lasting
cootrol but also more iojury to the ornamentals. Simazine is probably the
safer material for certain plaots.
Impressive control of annual weeds was obtained with as little as
1 pound per acre. If we do not demand that one application give full season
control, low rates of application can be useful on small liners and on
species that are injured by the high rates.
Fall application of the triazines showed promise of being very helpful
in the control of quackgrass. The minimumrate of application necessary for
practical control was not determined, but it would appear to be between
2 and 5 pounds per acre. Timely cultivation the following season may be
important in obtaining control of quackgras8 with reasonable rates,
The author wilhes to acknowledge a grant in aid from
Stauffer Chemical Companywhich partially supported thil work.