Vol. 15—1961 - NorthEastern Weed Science Society

426.
(Kalmia angustifolia) ,huckleberry (0 lussacia baccata), low bush blueberry
(Vaccinium vacillans.), Japanese honeysuckle Lonicera japonica) J and mapleleafed
viburnum (Viburnum acerifolium).· Those most commonly encountered
yhich grow ovar 4' high are high bush blueberry (Vaccinium cory:rr;,bosumand
V. atrococcum), bayberry (Myrica pensylvanica) J winterberry (~ verticillata),
sweet pepperbush (Clethra alnifolia), mountain laurel (Kalmia latifolia),
Virburnums (Viburnum spp.) '. alder (Alnus ~), flowering aogwooa (Cornus
florida), swamp azalia (Rhododendroii viscosum), pinkster flower (Rhododendron
nudifloriumr, spiabush (Lindera benzoin), barberry (Berberis vulgaris),
witchbazel (Hamamelis virginiana). These species are most desirable and
permissible along the edge of the right-of-way. However, some utilities
will also permit these species to persist directly under the lines if scattered
in occurrence. The abundance of greenbrier and its tendency to crowd
out other more desirable species and form impenetrable thickets is a local
problem in this part of Connecticut and requires some modification in the
management procedures as will be pointed out later. In 1954the tree growth
was cut and allowed to resurge for subsequent treatments.
Evaluation
of Spray Techniques
Since 1953 over 40 plots 50' x 50' or larger have been established under
or along the lines. Here various techniques have been employed using knapsack
sprayers as well as commercial power equipment. In order to achieve
the management objectives outlined, the spraying has been done selectively
except for special plots where the aim was to determine the effect of indiscriminate
applications. The various techniques employed include the basal,
root-collar, dormant stem, ste~foliageJ notching, frilling, and stump treatments.
Some of the formulations and seasons of applications along with comments
on effectiveness are given in Table I.
Although the basal technique gave effective root-kill in all seasons,
root-collar applications were even more effective, as has been reported by
other investigators (12,13). Trees up to 3" in diameter were root-killed
using the root-collar technique which involved thoroughly wetting the soil
around the root-collar. One very definite advantage of this method over the
basal technique is that the chemical is specifically directed to the rootcoilar
area. Therefore, the problem of accumulated leaf-litter around the
stems preventing run-down totPe root-collar is eliminated. For root-suckering
species mid to late sunmerapplications were most effective. When concentrations
were reduced to 1: 30, whiteoak showed some resistance with only 35%%
root-kill.
Both of these techniques have been extensively used on the demonstration
area and are highly recommended for right-of -way maintenance. Along with
obtaining effective root-kill they can be applied very selectively, thus
enabling one to preserve desirable shrubs and maintain a tight. ground cover
wherever it exists. Similar findings have been reported on the Penelec rightof-way
in central Pennsylvania (14).· .
The dormant stem technique was employed on greenbrier as well as tree
sprouts. Although formulations in oil are known to be effective,little work
has been done with Oil-water and water carriers. Data indicate that effective
root;.kill resUlts when relatively high concentrations (1:20) are applied in
water (TabJe I). By eliminating oil less damage results to desirable species.
It has been found that this technique is especially adaptable to situations