Vol. 15—1961 - NorthEastern Weed Science Society

411.
Some of the earlier work with Urab as a brush killer was
conducted in Tennessee, Texas, North Carolina, and Florida.
L. H. Prescott (1), TVA, Chattanooga, Tennessee, obtained satisfactory
control of mixed brush consisting of oak, hickory,
maple, sourwood, dogwood and shortleaf pine, using both the
granular and oil or water miscible Urab formulations. The
Urab 22% Granular was applied directly on the soil 6-12 in
from the base of brush at rates of 2-6 oz per clump. The
liquid concentrate was injected undiluted up to 6 in into the
soil at the base of the brush with a Mack anti-weed Gun at
rates of 20-60 cc per clump. It was also diluted to 3% actual
Urab by volume with water or oil and applied as a basal spray.
The basal method was most effective.
In an extensive screening program conducted by the Department
of Range and Forestry of the Texas Agricultural Experiment
Station (2) to evaluate the possible use of granular and pelletized
herbicides for selective control of woody plants on range
lands, Urab 22% Granular was one of several chemicals tested.
Applications were made in the late Spring of 1959 on post and
blackjack oaks, running live oak, water and wtllow 9aks, persimmon
and smilax at rates of 8.8 to 26.4 lb/A aqtive ingredient.
Good initial defoliation was noted from broadcast applications
at rates of 8.8 to l7~6 lb/A on persimmon, running
live oak and post oak growing on deep sandy soils. Application
of 17.6 lb/A in strips 5 to 7 ft apart gave good topkill of post
oak and running live oak. Smilax showed little response to
the treatment.
During 1959 and 1960 Urab has been under test at various
locations throughout the Northeastern United States and in the
prOVinces of Ontario and Quebec in Canada. Urab has been
successfUlly applied using hydraulic sprayers, mist biowers,
knapsack sprayers, fertilizer spreaders and seeders, and by
helicopters and fixed wing aircraft. Urab granular, pellet and
liquid concentrate formulations have been applied, and the
chemical appears to be particularly promising for the control
of conifers, white and yellow birch, willow and oak infesting
railway and utility right-of-ways.
In September, 1959, at Cookshire, Quebec, Urab Liquid
Concentrate was appl~d as an overall foliage and bark coverage
treatment at the rate of 2 gal/250 gal water/A to a stand of
mixed brush consisting of white and yellow birch, red maple,
conifers, willow and black cherry. The heighth of the trees
varied from some less than 6 ft to trees 20-25 ft high. One
year after the Urab was applied, all gr~wth up to 6 ft high with
the exception of red maple is dead. Cedars, spruce and black
cherry 6-20 ft high, and most willow and birch are dead, and
the remainder are 90% or more defoliated with only small distorted
sucker leaf growth apparent. Control of red maple varies
from complete kill of most of the smaller trees, to partial to
complete defoliation and kill of the larger 20-25 ft 'high trees.
Some of these maple trees with extensive root systems are dead,
others exhibit light sucker re-growth and still other exhibit