treatment of trees up to 4)5 m high. In spite of this, if the
forward speed adopted in the test is not exceeded,
the stability and the control are satisfactory.
The biological tests, even for only 1 year, show that the
prototype at a medium volume can o!er the same protection
as a traditional sprayer at high volume and performance
could be even better when the protection required
at the higher parts of the trees is more important.
The main defects of the prototype are the high concentration
of the losses under the trees and the asymmetry
of deposit on the outer sides of the canopy. While the
"rst is common to all the tunnel sprayers and
hardly improvable, the second could be corrected by
changing the number of the fans and the geometry of the
air#ow.