Vol. 15—1961 - NorthEastern Weed Science Society

511.
St.rips were run at 2o-.foot intervals,; ten strips involving approximately
2,000 .feet of travel covered an acre. This travel was carefully
gauged to be accomplished in 30 minutes, beoause the mist blowers in normal
operating situations put out 2i gallons of material in that time. Stand
area was measured on aerial photos be.fore spraying to help insure uniformity
of coverage at 2~ gallons per acre. The two mist blowers were operated in
tandem 20 feet apart. The man on the outside edge put out short strips of
toilet paper at frequent intervals to orient the inside man on the next
strip. When desirable, toilet paper was hung high on branches by putting it
in the air stream of the blower. About twenty acres per day were treated over
a five ...day period. Twelve five-gallon cans o.f spray formulation were taken
into the field each day, and two pack boards were used to carry the material
back into the .forest where necessary. Special oare was taken to agitate the
spray mixture before use.
AREASTRBATEDANDCONDITIONSDURINGTREATHEl'J'T
The seven areas treated by shoulder-mounted mist blowers from August 13
to August 20, 1958, represent a variety of conditions where small portable
mist blowers could be effeotive. A major limitation of this machine is the
relatively low height to which the material can be carried in the air stream.
Twenty feet of height is easy to achieve, thirty feet can be secured in still
air by holding the nozzle in one place, to let the air stream build up. The
great advantage of shoulder-mounted machines is their portability.
Area 1 was a stand of sapling hardwoods 20 to 30 feet tall over natural
-- white pine 4 to 10 feet in height. Hardwood species were prinoipally birches,
maples, and oaks with a few aspen and ash. A hard driVing rain interrupted
the work at 4:00 p.m., and probably washed some of the spray material from
the trees. The work in this stand continued next day on a damp, foggy
morning when the leaves were drenched with water. The leaves dried off
during the day, but another hard rain fell at 7:00 p.m. The wind was still
during this test.
Area 2 was an eight-year old Norway spruce plantation invaded by hardwoods,
white pine, and woody shrubs. The hardwoods were predominantly red
maple and pin cherry with heights ranging up to 20 feet. Some parts of the
plantation were heavily invaded by hardwoods, other parts had none. The
machines were shut off where there were no hardwoods to kill. Stone walls
through the area had hardwoods up to $Of tall which were also sprayed. The
plantation rows served to locate travel lines for the machines. This work
was done on a hot muggy day. Wind movement was less than five miles per
hour. The leaves were wet at the start and became dry during the operation.
A hard rain fell that, evening at 7:00 p.m.
Area 3 was a natural stand of white pine invaded by aspen, gray birch,
pin cherry, and a few white birch and red maple. The pine was 1$ to 20 feet
tall,; the hardwoods were 20 to 40 feet tall with diameters rangi.ng from 2"
to 12 11 • In most areas the hardwood existed as single scattered trees not
severely competing with the pine. In other areas the hardwoods were more
dense, of larger size, completely overtopping the pine. The trees were wet,