Vol. 16—1962 - NorthEastern Weed Science Society

The 1959 and 1960 replicated field plots variedinsie,e and de~~
depending upon the availability of 'species, plant characteristics and the number
of replications. Plot sizes ranged from 9 to 27 square feet and replications
from 2 to 14. All plant rnaterials were grown on well-drained sandy lOalllB~ .. ;., ....
The formulations used included DACTHALW-50~DACTHAL G-5F~ a five
percent fast water disintegrating granular and one' and one-half percent granulars
in two ,formulattone, DAC'lHAL;~l.5F and DAC'lHAIt'G-l.5S,; DACTHALG-l'.SF
has the prope:ptyof .relatively fast ,water-dhintegr&!ll1onin comparison with
DACTHALG-l.5S. Tb.e~e granulat"f'oI'lllulations were applted at rates to give',
10 and 15 pounds active per acre on the herbaceous ornamental group and 5)'10
and 15 pounds active on the woody ornamental species.
The wettable powder was mixed with water for application at the rate
of 150 gallons per acre with a small plot sprayer. The granular formulations
were applied by hand with a perforated shaker 'for,e_e of application and to
obtain unUormity in. distributiOn. The plots were treated as soon as possible
after transplanting, usually the ro1i6wing day. In some instances, where
treatments were delayed because of inclement weat!J.e;rJthe plots were handhoed
beforeprt:j;;.'Emlergence treatments.
.'
Weed c"bntrol data were obt'ained by making weed counts of the entire
plot area , except in the case of RhOdodendron mo11e;(plots~ where the high
purslane popUlation dictated counting' a measured small plot sector~ Weed
counts were made twice at approximately 5 and 11 weekS after applications.
Plant response or injUry evaluation was based on observational
ratings on a scale of 0 .. no injury to 11 • entire plant dead. These ratings
were made at the time of the two weed counts.'"
During 1961 ~ woody shrubs i. bare-rooted tr$~ liners and perennial '
herbaceous transplants were planted in two adjacent:'ireas of approximatel;y'
three-fourths acres each. The ornamental species in'each of these areas were
planted in double rows with three of each species opposite one another in
adjacent rows. This gave a total of six plants of each species grouped together.
The plantings were replicated four times in each area for a total of 48 plants
of each s pedes. Seeded annual and perennial flowei-ing species were planted
in one and one-half foot sections within each row. The two areas were on a
poorly.;drained Caneadea silt loam. i,
One area' was sprayed with' DACTHALw-50' atthe rate ··6f 10 pounds
active per acre and the other with the same formulati!c)1'l at 15 pounds acM,ve
per acre. A 50..gaJlLon, tractor-mounted low pressureIPTO:"driven field gpta;rer
was utUizedfor app¥ng DACTHALherbicide under actual field conditions.'
It had a boom·containing a Tee Jet 8006 nozzle and the sprayer was operat13d
to deliver 56 gallons of water per acre. All crops except the trees were
treated with a topical application> pre-emergence t~ tihe weeds. Application
was made on a band 20 inches wide. The trees were spra:red on eaoh side of' the
row pre-emergence to weeds with the nozzle placed on the end of the boom to
cover a swath 20 inches wide from two sides. Some overlapping in this application
occurred.
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