Smith, H. Clay. Forest management guidelines for controlling
wild grapevines. Res. Pap. NE-548, Broomall, PA: U.S. Depart:
ment of Agriculture, Forest Service, Northeastern Forest
Experiment Station; 1984. 15 p.

Grapevines (Vitis spp.) are becoming a major problem to forest
managers in the Appalachians, especially when clearcutting

is done on highly productive hardwood sites. Where present,
grapevines can reduce tree quality and growth, and eventually
kill the tree. Silvical characteristics of grapevines are discussed
as background for grapevine control. Forest management guide-
lines are given for controlling growth of grapevines.

441 6 176.1 (Vitis; Central Appalachian hardwoods)

Keywords: grapevines, control guidelines, silvical characteristics

¥ U.S. GOVERNMENT PRINTING OFFICE; 1984—705.029/522


Few options exist when applying
grapevine control measures to young
stands. Also, because grapevines can
quickly become a problem when as-
sociated with other factors such as
snow and ice, it is important that the
grapevine control measures be used
in these stands as early as possible.
Though herbicides can be used suc-
cessfully, basal spraying individual
vines with herbicides may be more
costly than cutting, and herbicide
movement in the soil could be more
risky to residual trees in the stand.
Also, in immature stands, the diam-
eters of the vines are much smaller,
there are more vines, and usually
vines are cut with one swing. Thus,
cutting the grapevines near ground
level with a tool such as a Woods-
man’s Pal or Swedish brush axe is the
recommended practice (Fig. 6). This
cutting should be done when the
codominant trees in the stand are at
least 15 feet tall and a well-developed
closed canopy is present because
shading is the key to successful
grapevine control.

The cut grapevine stumps will
sprout, but the majority of the sprouts
will die within a few years. Usually,
the grapevine cutting can be done in
the stand less than 10 years after
clearcutting. Also, if the codominant
trees average 15 feet tall, it is easier
for the cutters to walk through the
stand to locate and treat the grape-
vines. It is easy to miss grapevines,
and a few inches of snow on the
ground aids the crew. When treating
the vines, the crew should work across
the slope contour and crew members
should have overlapping lines. In
cutting grapevines under ideal condi-
tions, a good cutting crew will cut
about 95 percent of the grapevines.

10

Figure 6.—Cutting grapevines in a young immature stand.

Cost to sever vines. Time required
to sever grapevines in young, imma-
ture stands has been determined
using regression techniques (Smith
and McCay 1979). More data were
added since 1979, and all available
data were combined (Table 2). A total
of 15 young, even-aged stands were
used to develop a regression. In the
regression, number of grapevines per
acre accounted for about 95 percent

of the variation. Immature stands
with 100 grapevines per acre require
about 1.15 man-hours to cut grape-
vines while stands with 1,000 grape-
vines per acre should take about
5.65 man-hours to cut the grapevines.
Thus, at $7.00 per man-hour, the cost
to cut 100 grapevines per acre would
be about $8.00 while cutting 1,000
grapevines per acre cost about $39.50
an acre.


Introduction

Wild grapevines (Vitis spp.) are
becoming a major problem for the
forest manager in many areas of the
Appalachians. A few years after clear-
cutting, it is not unusual to find large
numbers of grapevines growing in
young stands on good to excellent
hardwood sites—where the faster
growing, more valuable timber exists.
Often the reproduction in hardwood
stands is excellent, but the presence
of grapevines can convert portions of
these excellent stands to a mass of
grapevines.

Grapevines damage hardwood
trees by breaking tops and limbs,
twisting and bending the tree bole,
and uprooting trees, thus reducing
tree quality and eventually killing the
tree (Fig. 1). Once grapevines get into
the tree crowns, especially in young
stands, the potential for future pro-
duction of quality timber products is
severely reduced. No tree damage
information related to grapevines has
been reported; however, as the num-
ber of grapevines per acre increases,
more trees have grapevines in crowns,
and thus, a higher risk in loss of qual-
ity. Many forest managers are con-
cerned about grapevines and want
information on growth control.

Wildlife managers are also con-
cerned about measures to control
grapevines because the vines pro-
duce food and cover for many species
of wildlife. The U.S. Fish and Wildlife
Service indicates that at least 80
species of birds and a large number
of animals eat grape berries (Shutts
1968). Martin and others (1951) report
that black bear, raccoon, quail, grouse,
turkey, and a host of songbirds eat

grapes. Deer browse foliage and
stems in the spring and early summer
and eat fallen leaves during the winter
months (Massey 1961). Birds often
use the stringy bark for nest con-
struction, and squirrels build leaf
nests in trees with grapevines in the
crowns (Martin et al. 1951, Sanderson
et al. 1980). Grapevines grow quickly
in clearcut openings and, according
to Crawford (1971), often produce the
only dependable food for wildlife
during the early years after a tree
regeneration cutting practice. Also,
during the summer, grapevines pro-
vide excellent escape and nesting
habitat for songbirds.

Thus, because of the importance
of grapevines to wildlife and because
of concern that grapevines reduce
tree quality, the control of grapevines
growing in a forest stand is highly
controversial. However, considerable
research has been done on grapevine
control, and we know much about
grapevine characteristics and re-
sponse to control treatments. We
review the research and provide rec-
ommendations for controlling the
development of grapevines in given
conditions. Users must decide how or
what portion of these guidelines to
implement.

Considerable research informa-
tion is available for two species of
wild grape, summer grape (V. aesti-
valis Michx.) and its variety silverleaf
grape (Var. argentifolia Munson).
Although wild grapes range through-
out most of the Eastern United States,
Shutts (1974) indicated that grapes
are not common in the northern part
of the range.

Growing Sites

Wild grapevines grow on a wide
range of soil and site conditions.
Often grapevines grow best under
moderately moist conditions in dense
ravines on southeastern slopes where
organic matter has accumulated
(Shutts 1968). In West Virginia, grape-
vines were directly related to site
quality, that is, as the site quality
increased, grapevines became more
abundant (Trimble and Tryon 1979).
In Virginia, Shutts (1968) reported six
grapevines on every good site com-
pared to one on every poor site. Ina
later report, Shutts (1974) stated that
vines are less resistant to disease on
the good moist sites.

Growth and Reproductive
Characteristics

Growth

Grapevines in the Appalachians
are similar to other woody plants in
that each year a growth ring is added
to the ring-porous stem (Trimble and
Tryon 1979, Stiles 1980). Also, vines if
wounded just before or during the
growing season, characteristically
bleed sap. In West Virginia, this bleed-
ing occurs from early spring to about
mid-September.

Wild grapevines sprout prolifically
when cut, the stems produce epi-
cormic branches when exposed to
sunlight, and the vines root or layer
easily. Grapevines are intolerant of
shade; prolonged shade reduces
growth and will kill the vines.

Grapevines are supported by
tendrils that enable the vines to climb


Headquarters of the Northeastern Forest Experiment Station are in
Broomall, Pa. Field laboratories are maintained at:

©@ Amherst, Massachusetts, in cooperation with the University of
Massachusetts.

© Berea, Kentucky, in cooperation with Berea College.

© Burlington, Vermont, in cooperation with the University of
Vermont.

©@ Delaware, Ohio.

© Durham, New Hampshire, in cooperation with the University of
New Hampshire.

© Hamden, Connecticut, in cooperation with Yale University.

© Morgantown, West Virginia, in cooperation with West Virginia
University, Morgantown.

© Orono, Maine, in cooperation with the University of Maine,
Orono.

© Parsons, West Virginia.

© Princeton, West Virginia.

© Syracuse, New York, in cooperation with the State University of
New York College of Environmental Sciences and Forestry at
Syracuse University, Syracuse.

© University Park, Pennsylvania, in cooperation with the
Pennsylvania State University.

©@ Warren, Pennsylvania.



Literature Cited

Crawford, H. S., Jr. Wildlife food on
three Ozark hardwood sites after
regeneration cutting. Journal of
Wildlife Management. 35:533-537;
1971.

Della-Bianca, Lino. Characteristics,
habitat, and fruiting of wild grape-
vines in the southern Appalachians.
Journal Elisha Mitchell Science
Society. 94:21-26; 1978.

Della-Bianca, Lino. Fruit production
by summer grape in southern Ap-
palachians. Journal of Wildlife
Management. 43:579-583; 1979.

Fernald, Merritt Lyndon. Gray’s man-
ual of botany. 4th ed. New York:
American Book Company; 1950.
1,632 p.

Hamel, Dennis R. Forest Management
chemicals—a guide to use when
considering pesticides for forest
management. Agric. Handb. 585.
Washington, DC: U.S. Department
of Agriculture; 1983. 645 p.

Kochenderfer, J. N.; Wendel, G. W.
Plant succession and hydrologic
recovery on a deforested and herbi-
cided watershed. Forest Science.
29(3):545-558; 1983.

Martin, A. C.; Zim, H. S.; Nelson, A. L.
American wildlife and plants. A
guide to wildlife food habits. New
York: Dover Publications; 1951.
499 p.

14

Massey, A. B. Summer grape. In: Deer
browse plants of southern forests.
U.S. Department of Agriculture,
Forest Service, Southern and South-
eastern Forest Experiment Sta-
tions; 1961. 77 p.

Sanderson, H. Reed; Nixon, Charles
M.; Donohoe, Robert W.; Hansen,
Lonnie P. Grapevines—an important
component of gray and fox squirrel
habitat. Wildlife Society Bulletin. 8:
307-310; 1980.

Shutts, Lynn Merrill. Autecology and
fruit production of summer grape
(Vitis aestivalis) and silverleaf grape
(V. aestivalis var. argentifolia) in
the Virginia highlands. Blacksburg,
VA: Virginia Polytechnic Institute;
1968. 55 p. M.S. thesis.

Shutts, Lynn M. Summer grape. In:
Gill, John D.; Healy, William M.,
compilers. Shrubs and vines for
northeastern wildlife. Gen. Tech.
Rep. NE-9. Broomall, PA: U.S. De-
partment of Agriculture, Forest
Service, Northeastern Forest Ex-
periment Station; 1974:52-53.

Smith, H. Clay. Killing grapevines
with herbicides. Northern Logger
and Timber Processor. 25:9,33; 1977.

Smith, H. Clay. Managing central
Appalachian hardwood stands. In:
Proceedings, National silviculture
workshop-hardwood management;
1981 June 1-5; Roanoke, VA.

Roanoke, VA: U.S. Department of
Agriculture, Forest Service; 1981:
185-195.

Smith, H. Clay; McCay, Roger E. Esti-
mating time required to cut grape-
vines in young even-aged hardwood
stands. Southern Journal Applied
Forestry. 3:125-127; 1979.

Smith, H. Clay; Smithson, Paul M. Cost
of cutting grapevines before log-
ging. Res. Note NE-207. Broomall,
PA: U.S. Department of Agriculture,
Forest Service, Northeastern For-
est Experiment Station; 1975. 4 p.

Stiles, H. D. Growth cycle of the grape-
vine. Basic inner workings of the
vine. Vinifera Wine Growers Jour-
nal. 7(3):181-185; 1980.

Strausbaugh, P. D.; Core, Earl L. Flora
of West Virginia (Part I). Morgan-
town, WV: West Virginia University;
1952; W.V. Univ. Bull. Ser. 52 No.
12-2. 1,075 p.

Trimble, G. R., Jr; Tryon, E. H. Silvi-
cultural control of wild grapevines.
Morgantown, WV: West Virginia
University; 1979; W.V. Univ. Agric.
For. Exp. Stn. Bull. 667. 19 p.

Wendel, G. W. Longevity of summer
grape seed stored in the forest
floor. Wildlife Society Bulletin, 9:
157-159; 1981.


Finally, in a hydrology study on
the Fernow Experimental Forest, herbi-
cides were applied to a 60-acre area
periodically throughout the growing
season for 7 years. The objective was
to kill all vegetation for the 7-year
period. Several different kinds of
herbicides were used (primarily 2,4,5-T;
2,4-D; Dalapon) (Kochenderfer and
Wendel 1983). All grapevine stems
were killed during the herbicide treat-
ment. After 7 years, the herbicide
application was stopped and the
stand was allowed to regrow naturally.
Initially, the vegetation development
was Sparse, but 13 years after the last
herbicide treatment, seedling grape-
vines are in the tree crowns of many
trees in the 60-acre stand.

To summarize, herbicides kill
grapevines and minimize grapevine
sprouting, but herbicide treatments
applied before an even-age cutting
practice will not control seedling-
origin vines that germinate after
cutting. The success of spraying vine
stumps seems to vary with the time
of application and success of stump
spraying seems to be related to the oc-
currence of stump bleeding. The tests
were done in August, mid-September,
early March, and April. Profuse bleed-
ing occurred during the August and
April stump treatments. No bleeding
was observed at the September or
March treatments. Success in killing
vines was best during mid-September
and early March.

Grapevine Arbors

in stands where grapevines are
found, openings often develop in the
crown canopy. In these openings,
the vines become matted, overtop the
trees, and develop an entanglement
that primarily is dominated by grape-
vines. We call these open areas wild
grapevine arbors or grapevine clumps
(Fig. 5). To my knowledge, there is no
practical way to eliminate grapevine
arbors. However, grapevines in the
trees bordering the openings can be
cut to keep the arbor from enlarging.
If the grapevine arbors are small
enough, the crown canopy from the
overstory border trees may eventually
close, thus shading the grapevines.
In large arbors, crown encroachment
from border trees will not occur. Gen-
erally, in established grapevine ar-

bors, it is not possible to grow quality
hardwood timber for many years.

No doubt it is difficult to control
the growth of grapevines within an
arbor by using existing techniques.
Practical herbicide applications will
not prevent the emergence of grape
seedlings, and cutting the vines will
simply stimulate sprouting. Where
the forest management policy is to
maintain some grapevines for wildlife
purposes, arbors seem to be the logi-
cal places to grow vines while the
rest of the stand is subject to grape-
vine control treatments. However,
even after designating a desired
number of arbors, additional arbors
may be present.

Figure 5.—Grapevines dominating the stands—a wild grapevine arbor.


Figure 2.—Clusters of grape berries.

Grapevine Control in
Forest Management

Grapevine control must be con
sistent with management objecti
If the objective is to grow only hight,
quality timber, then elimination of all
grapevines could be the control treat-
ment. If wildlife development is the
sole management objective, then
grapevine growth and reproduction
could be maintained or stimulated.
However, in most situations forest
managers want to grow good-quality
timber and at the same time encour-
age wildlife. To meet this objective,
grapevines should be controlled by
treatments that provide enough grape-
vines for recommended wildlife pur-
poses, while trying to keep grapevines
out of the crown of trees designated
for the production of quality timber.
Thus, forest managers must consider
a number of situations when con-
trolling grapevines.

Usually, most grapevine problems
exist on the better sites (oak site
index 70 and higher). Grapevines also
become a more serious problem to
forest managers when silvicultural
practices such as clearcutting are
used instead of partial-cutting prac-
tices such as individual-tree selection
or a commercial thinning (Smith 1981).
The keys to grapevine control are
herbicides or canopy shading. Herbi-
cides usually are highly successful in
killing vines. Likewise, since the
intolerant grapevines need light,
shade from the overstory canopy also
effectively controls grapevines espe-
cially stump sprouts.


and advance on vegetation. Trimble
and Tryon (1979) suggest that most
grapevines become attached to the
tree crown when the trees are young.
Grapevine shoot growth begins later
in the growing season than that for
other plants, and shoot elongation
starts slowly for several weeks, fol-
lowed by periods of rapid growth.
Shutts (1968) reported that while
shoot growth is rapid, diameter growth
is slow. A 50-year-old vine may have
a diameter at ground line of only 1.5
inches. Normally sprout shoot growth
is rapid. Annual shoot growth of some
young stump sprouts was 15 feet or
more (Trimble and Tryon 1979). How-
ever, grapevine seedlings grew slower
than many tree species. Two growing
seasons after clearcutting, grapevine
seedlings averaged 0.5 feet tall, yellow-
poplar 1.1 feet, and black cherry 2.2.
However, the grapevine seedlings
grew about as fast as yellow-poplar
the first year, but during the winter,
many grapevine tops had died. Other
vegetation such as blackberries out-
grew young grapevine shoots. Trimble
and Tryon (1979) observed 70,000
grapevine seedlings per acre the first
year after clearcutting, and 5 years
later 1,975 grapevines per acre sur-
vived competition of other plants. Of
the survivors, 139 per acre were climb-
ing the forest vegetation, but not
causing any major damage to the tree
boles or crowns.

Flowering

Wild grapes normally produce
male and female flowers on separate
vines from mid-May to early July
(Fernald 1950). Some vines also pro-
duce perfect flowers which means
that a single vine may produce seed—
thus even “male” vines are capable of
bearing seed (Strausbaugh and Core
1952). The flower pollen is dissemi-
nated by wind, rain, insects, and ani-
mals. In North Carolina, Della-Bianca
(1978) observed that flowers bloomed
and were pollinated during the first
2 weeks in June, and tiny grape berries
were seen in late June. Frosts did not
seem to have any effect on flowering.

Seed Production

Grape seed crops are variable
and fluctuate from year to year, but
moderate seed crops occur in most
years. Grapevines can produce seed
the third year after establishment
(Shutts 1968), and the seed normally
tipens to a dark purple in September
and October (Massey 1961). Overhead
shading of grapevines results in poor
grapevine seed production. Grape
seed can remain on the vine through-
out the winter, but Shutts (1968) and
Della-Bianca (1978) found the greatest
amount of seed on the ground about
mid-November. Cispersion of seed is
largely by wind, animals, and gravity;
however, inclement weather, such as
high winds accompanied by rain and
snow, can increase seed dispersion
(Della-Bianca 1978). Periodically, large
quantities of seed are produced and
the seed can remain viable in the soil
duff for many years. Wendel (1981)
reported that about 3 percent of the
grape seed stored in the soil had the
potential to germinate annually and
this percent was consistent through-
out the years for at least an 11-year
period.

Della-Bianca (1978) reported that
an average of 96 vines per acre, with
an expected 50:50 male to female vine
ratio, produced about 1,012 grape
clusters per acre per year for 2 years.
If the average cluster had 42 berries,
about 42,500 berries per acre would
be produced (Fig. 2). Also, if each
berry contained 3 seeds (range nor-
mally 2 to 6), 127,500 seeds per acre
could be produced annually. In an-
other study, Shutts (1968) found that
six female vines produced about 9,350
grape berries or 28,050 seeds in one
season. Shutts further reported that
the number of grape clusters per vine
increased with the diameter of the
vine. However, wild grape seed is
susceptible to insect and disease
damage. A common disease, black rot
(Guignardia bidwellii), destroyed 40
percent of the seed crop (Shutts 1968).
Also, Curculio beetles (Craponius
inaequalis) destroyed more than 50

percent of the seed crop (Della-Bianca
1978, 1979). Thus, of the total seed
produced in a poor year, we might
expect less than 10 percent of the
seed production to be available for
seed germination. However, 10 per-
cent of an estimated average seed
crop could still yield 12,750 available
grape seeds per acre.

Although frost does not have
much effect on flowering, excessive
moisture (rain or high humidity) leads
to the development of fungal diseases
that destroy the fruit (Shutts 1974).
The shoots of the grapevine are sub-
ject to both cold and heat injury. A
sudden rise in temperature in late
spring may result in damage to the
shoot tip. Spring frosts often damage
foliage if warm weather and rapid
growth precede a sudden drop in
temperature (Shutts 1974). Overhead
shading minimizes the production of
grape berries (Della-Bianca 1978).


Caution

Pesticides used improperly can be injurious to man,
animals, and plants. Follow the directions and heed all
precautions on the labels.

Store pesticides in original containers under lock
and key—out of the reach of children and animals—and
away from food and feed.

Apply pesticides so that they do not endanger hu-
mans, livestock, crops, beneficial insects, fish, and wild-
life. Do not apply pesticides when there is danger of drift,
when honey bees or other pollinating insects are visiting
plants, or in ways that may contaminate water or leave
illegal residues.

Avoid prolonged inhalation of pesticide sprays or
dusts; wear protective clothing and equipment if specified
on the container.

If your hands become contaminated with a pesticide,
do not eat or drink until you have washed. In case a pesti-
cide is swallowed or gets in the eyes, follow the first aid
treatment given on the label, and get prompt medical
attention. If a pesticide is spilled on your skin or clothing,
remove clothing immediately and wash skin thoroughly.

NOTE: Some States have restrictions on the use of cer-
tain pesticides. Check your State and local regulations.
Also, because registrations of pesticides are under con-
stant review by the Environmental Protection Agency,
consult your local forest pathologist, county agricultural
agent, or State Extension specialist to be sure the in-
tended use is still registered.

Ye Posticided Safely

FOLLOW THE LABEL

US, DEPARTMENT OF AGRICULTURE

15


Tordon 101R applied to the cut surface of a grape-
vine stump during early March and mid-September effec-
tively killed grapevines. Tordon 101 applied in April did
not consistently kill vines.

4. Roundup (Glyphosate)
Roundup mixed as a 20 percent solution of chemical
and water and applied as a basal spray to the cut
surface of grapevine stumps in early March (stumps
not bleeding sap), mid-August (stumps bleeding sap),
and mid-September (stumps not bleeding sap).

Results

Roundup effectively killed the grapevines in early
March and mid-September, but results were poor in
mid-August.

5. Frill technique
Roundup, Weedone 170, Tordon 101R, and 2,4,5-T were
applied using a frill technique. Herbicides were ap-
plied only to the frill cut using the oil and water herbi-
cide solutions mentioned. This frill application was
done in mid-September (vines not bleeding sap).

Figure 4.—Basal spraying both ends
of a layered grapevine.

Results

Frilling grapevines and treating the frills with herbi-
cides was not effective.

6. Mistblowing technique
Grapevine foliage was mistblown with 2,4-D and Tordon
101 (Smith 1977) and Tordon 10K pellets (80 Ibs per
acre) were applied to grapevine arbor areas. All herbi-
cides were applied in mid-July.

Results

Ground mistblowing of the grapevine foliage with
2,4-D and Tordon 10K was effective but limited to contact
with foliage. Aerial spraying would be better, but no
herbicide is selective for grapevines only. Therefore,
other woody vegetation would be killed also. Tordon 10K
pellets were successful in killing the grapevines, but
other nearby vegetation was killed too.


WE-3Yd Laat Copy

Z£P |
O1@ veneers, Forest Management Guidelines

Agriculture

Forest Service for Controlling Wild Grapevines

Northeastern Forest
Experiment Station

Research H. Clay Smith

Paper NE-548

1984



Table 1.—Number of man-hours per acre to cut
or basal spray grapevines and
a

gallons of bas:

spray mixture

used per acre (mature stands).

Man-hours/acre to—

Number
treated Cut? Basal spray” Herbicide-oil
vines vines vines mixture
Gallons
10 0.67 0.47 0.02
25 92 54 18
50 1.33 67 46
100 2.20 92 1.01
150 3.00 1.17 1.56
200 3.80 1.42 2.11
300 - 1.92 3.21
500 - 2.92 5.41

@Man-hour estimates include a 10 minute per man-hour allow-
ance for periodic crew breaks—each crew member cut vines.

>Man-hour estimates include a 10 minute per man-hour allow-
ance for periodic breaks—two-man basal spray crew.

grapevine cutting control area and a
lunch break were not included in the
cost. One factor not evaluated was

size of grapevines. It is difficult to cut
large vines with hand tools. Some-

times vines are so large that it would
be easier to girdle than cut the vine.

Cost to basal spray vines. Costs
to basal spray grapevines in mature
hardwood stands were also deter-
mined. Knowing the number of grape-
vine stems sprayed per acre and the
man-hours required to do the spray-
ing, an equation was developed from
the data that accounted for most
of the variation (97 percent). Eight
treatment areas were evaluated. A
2-man crew did the basal spraying—
one crew member sprayed and the
other mixed and hauled the herbicide.
Slopes ranged from 15 to 35 percent.
The treatment areas used to collect
this basal spray cost data were small,
less than 2 acres. These areas were
much smaller than the cut-vine areas
of nearly 100 acres. Mixing, hauling,
and supplying the basal spray appli-
cator with herbicides could not be
adequately evaluated in our basal
spray test areas. Thus, basal spraying
of vines in this instance is a minimum
cost estimate.

Areas with 10 sprayed grapevine
stems per acre required about 0.47
man-hours; 50 vines per acre, 0.67
man-hours; and to basal spray 200
grapevine stems per acre, 1.42 man-
hours were necessary (Table 1). Man-
hours for basal spraying include the
spraying of vine layers. Each basal
sprayed vine end was counted as a
vine though often because of layering
the same vine was basal sprayed
more than once. Also, if the mature
stand is going to be clearcut at least
4 to 5 years after the herbicide treat-
ment, it is not necessary to basal
spray the grapevine layers.

Grapevine diameters at ground
line for the basal sprayed vines aver-
aged about 1.6 inches and ranged
from 0.4 to 5.7 inches with about 25
percent of the vines 2.0 inches in
diameter and larger. This vine size is
typical in many mature stands regard-
less of whether the vines were cut or
basal sprayed. We used an herbicide-
fuel oil mixture that cost $1.47 per
gallon ($15.00 per gallon for herbicide,
$1.00 per gallon for fuel oil). The basic
mixture was 3.5 gallons of herbicide
added to 100 gallons of fuel oil. The
grapevine stems were basal sprayed
using a backpack sprayer and soak-
ing at least the lower 12 to 18 inches
of the grapevine stem and the root
collar. An average of 1.35 fluid ounces
was used per grapevine stem.

Using data in Table 1, we found
that the herbicide-fuel oil and labor
cost to basal spray 200 grapevine
stems (including layers) per acre ina
typical second-growth stand was:

1.42 man-hours to basal

spray vines @ $7.00

per man-hour =$ 9.94
2.11 gallons of herbicide

mixture @ $1.47 per

gallon = 3.10

$13.04

Thus, with 200 grapevine stems
per acre, it cost a minimum of about
$13 an acre to basal spray grapevines
in a mature stand. It cost $26.60 per
acre to cut 200 vines per acre.


Stand Silvicultural Treatments

Mature Stands—Uneven-age
Management (other partial cuts)

Normally, partial cuts such as
individual-tree selection, improvement
cuts, and some diameter limits result
in residual stands with considerable
shading of the understory. Grapevines
do not grow well under dense shading.
Grapevines can be controlled in ma-
ture stands by severing or cutting the
vines that grow in trees. Vines are
severed near ground line before, dur-
ing, or after logging by using blades,
hatchets or chain saws depending on
vine size. The cut vine stump will
sprout, but the sprouts will die within
a few years and barring any drastic
overstory removal or natural disaster,
the vines will not become a problem
in the future.

Large vines are hard to cut, and
it may be easier and not as expen-
sive to basal spray the vines with an
herbicide-oil solution. Spray the base
of the vines and root collar of only
those vines attached to the tree crown.
No other portion of the vines needs to
be treated in this instance. Though
we have not basal sprayed vines
during all months of the year, we
have found that in every instance
(early March, mid-April, mid-August,
mid-September) the vines died.

Thus, presence of grapevines in
mature stands where partial cuts are
planned should not present any major
control problems to the forest man-
ager. In fact, in some of these stands
there may not be enough grapevines
to satisfy wildlife management ob-
jectives. Thus, depending on forest
management objectives, grapevine
arbors may need to be established
artificially. Seedling-origin grapevines
are not a problem under the shade of
partially cut stands unless the stands
are suddenly opened up due to heavy
logging or a windstorm, ice storm,
and so on.

Mature Stands—Even-age
Management

Although grapevines are easier
to control in partially cut, mature
stands by simply severing or applying
an herbicide basal spray, control is
more complicated when any type of
even-age harvest cutting practice
(clearcuts, shelterwoods) is planned
for these stands. Control measures
must be considered for both sprout-
and seedling-origin vines. A basic
assumption is that if grapevines are
present before an even-age harvest
cut, grapevines will be abundant in
the next stand regardless of the pre-
harvest techniques applied to control
tne grapevines. If time and money per-
mit, the grapevines in the trees could
be severed near ground line at least
4 to 5 years before the stand is clear-
cut. The cut grapevine stumps will
produce sprouts, but the sprouts will
die within a few years from overstory
shading. Of course, the vines could
be basal sprayed with an herbicide-oil
treatment if desired. Grapevine sprout-
ing should not be a problem after
clearcutting, but seed-origin vines
will be.

If an even-age harvest cut is
planned within 4 years or vine cutting
is not permitted, grapevines can be
controlled by basal spraying each
vine near ground line. It is also ad-
visable to spray the vine layers when a
harvest cut is planned within 4 years.
The 2,4-D; 2,4-DP herbicide-oil mixture
applied as a basal spray on uncut
vines and vine layers is an effective
grapevine control treatment. How-
ever, any herbicide-oil basal spray
mixture should work well if grape-
vines are listed as a target species on
the label. After applying the herbicide
basal spray treatment, the stand could
be harvested. Usually, the new devel-
oping stand will still have a serious
grapevine problem from seedling-
origin vines, and a grapevine control

treatment will be necessary after the
new stand has developed a closed
overstory canopy. This canopy devel-
opment usually occurs when the
codominant trees average 15 feet tall.

When mature stands are sched-
uled for clearcutting within a few
years and forest managers want to
control grapevines but do not want to
use herbicides, the grapevines should
not be cut before, during, or after
logging. If the grapevines are cut, the
stumps will simply produce more
sprouts, and make the situation
worse. After clearcutting, some of
the uncut vine stems will produce
epicormic branches and roots along
the stem, a source for sprouting and
layering. Thus, when clearcutting,
there is no easy, inexpensive way to
control the vines in the mature stands
before cutting that will eliminate the
application of a grapevine control
treatment in the regenerated stand.
For thinnings, vine control methods
are similar to recommendations for
partial cuts in mature stands.

Costs to sever vines. Costs to
sever grapevines in mature stands were
summarized by Smith and Smithson
(1975). Since 1975, more data have
been collected, and a prediction equa-
tion was determined to summarize
the data based on 11 areas. However,
results varied from the 1975 data. We
estimated that mature stands with 10
grapevines per acre required about
0.67 man-hours to sever grapevines
while stands with 50 grapevines per
acre required about 1.33 man-hours
and stands with 200 grapevine stems
per acre required about 3.80 man-
hours (Table 1). Thus, at $7.00 a man-
hour it cost about $9.30 per acre to
cut 50 grapevines and $26.60 to cut
200 grapevines. These man-hour esti-
mates include periodic breaks (about
10 minutes per man-hour) for the cut-
ting crew, but travel to and from the


Herbicides

Herbicides are often used to
control wild grapevines and some are
very effective. Presently, the best
grapevine herbicide treatments are
those applied to the foliage or at the
base of the vine trunks. However,
grapevine foliage is often beyond
reach of mistblowers, and aerial ap-
plication is not justified because
there is no available herbicide selec-
tive for grapevines alone. Therefore,
an herbicide treatment such as basal
spraying the root collar and base of
the vine is the more realistic applica-
tion technique (Fig. 3). In many in-
stances, a recommended herbicide
treatment for individual grapevines
allows forest managers to choose the
number of grapevines to treat. Hamel
(1983) lists herbicide treatments to
control grapevine growth.

Several herbicides, treatment
techniques, and results that have
been used for grapevine control by
the USDA Forest Service in coopera-
tion with Dow Chemical Company,’
Monsanto Company, Monongahela
National Forest, Jefferson National
Forest, and West Virginia Department
of Natural Resources follow:

1. Weedone 170 (2,4-D; 2,4-DP)

a. Mixed herbicide with fuel oil following the label
instructions and applied as a basal spray to the
base and lower 12 to 18 inches of uncut stems in
mid-April, mid-August, mid-September and early
March.

b. Mixed herbicide with fuel oil following the label
instructions and applied as a basal spray to cut
grapevine stumps and surfaces in mid-September
(stumps not bleeding sap).

‘The use of trade, firm, or corporation names in this publica-
tion is for the information and convenience of the reader. Such
use does not constitute an official endorsement or approval by
the U.S. Department of Agriculture or the Forest Service of any
product or service to the exclusion of others that may be suitable.

Figure 3.—Basal spraying grapevines with herbicides.

Results

Grapevines are readily susceptible to 2,4-D herbicides
in fuel oil when applied as a basal spray to the base and
lower 12 to 18 inches of an uncut vine. Applying herbicides
in fuel oil to the stem and cut surface of the grapevine
was also successful in killing vines when applied in mid-
September. For best results, both vine ends of a layered
grapevine should be treated (Fig. 4) when a clearcutting
practice is planned within 4 years after the herbicide
treatment.

2. 2,4,5-T
Herbicide mixed in fuel oil following the label instruc-
tions and applied as a basal spray to the base of uncut
grapevine stems and 12 to 18 inches of lower stem.
Herbicide applied to cut grapevine stumps and sur-
faces in mid-September (stumps not bleeding sap).

Currently, 2,4,5-T cannot be recommended, but the
chemical was very effective.

3. Tordon 101; 101R
Tordon 101 mixed as a 50 percent solution of chemical
and water and applied as a basal spray to cut grape-
vine stump surfaces in April (stumps bleeding sap).

Tordon 101R applied undiluted as a basal spray to cut
surfaces of grapevine stumps in early March and mid-
September (stumps not bleeding sap).


|. (B) Grape-
his young

and uproot trees in thi

break,

Figure 1.—(A) Grapevines in a young immature hardwood stand.

vines and snow combined to bend,

immature hardwood stand.



Summary and Management
Recommendations

In many instances, grapevines
are highly desirable, particularly where
wildlife is the only concern of the for-
est manager. However, where quality
timber production is the primary
objective or where the multiple-use
concept is applied, the uncontrolled
growth of grapevines often conflicts
with growing quality timber and mast-
bearing trees. Forest managers need
to determine management objectives
before deciding what measures to
use to control grapevines. For exam-
ple, if wildlife is the sole management
objective, then grapevines may not
be controlled or treatments may be
used to increase grapevines. Also,
the sole wildlife objective could be
to grow as many grapevines and pro-
duce as many mast-bearing trees as
desirable. Grapevine control treat-
ments would be considered in this
instance. Where production of quality
timber is the sole objective, then an
effort could be made to eliminate all
grapevines in the managed stand.

However, in practice forest man-
agers usually want to manage stands
to produce quality timber and main-
tain an abundance of wildlife at the
same time. A muitiple-use manage-
ment approach is the retention of
wild grapevine arbors. The arbor
concept provides opportunities for
wildlife food and cover while simul-
taneously allowing the remaining
stand to be managed for quality hard-
wood timber as well as other resource
uses,

The research recommendation
to manage or Control vines in arbors
is to confine the vines to the arbors.
If grapevines in an arbor are cut, the
vines will sprout and thus increase
drastically. If the grapevines in an
arbor are treated with herbicides, the
vines will die, but the grapevine seed
in the soil duff will germinate and
grapevines will continue to thrive.

Controlling growth of grapevines
where overstory shading is present
involves cutting the vines and/or
spraying them with herbicides. Be-
cause grapevines are intolerant of
shade, severing the vines is usually
an effective control. Recommended
guidelines for controlling grapevine
development for given stands and
silvicultural management situations
are as follows:

1. Grapevine contro! practices should be applied in areas

with an oak site index 60 or higher.

2. Mature Stands Using Even-Age Silviculture and Man-

agement Practices

a. Stands to be harvested within 3 years.

Retain wild grapevine arbors.

Basal spray herbicides (2,4-D; 2,4-DP) on the lower
12 to 18 inches and the root collar of uncut grape-
vines attached to the tree crowns. Apply herbicide-
oil mixture to the layered vines along the ground
surface. Do not treat grapevines inside arbors.
Also, basal spray grapevines attached to the crowns
of trees surrounding the arbor openings.

If a basal spray herbicide cannot be used, sever
grapevines during the late winter, early spring, or
fall and spray the cut stump surface with Roundup
(20 percent solution) or Tordon 101R. Herbicides
should be applied when sap is not bleeding from
the cut stump.

. Stands to be harvested in 4 or more years.

Retain wild grapevine arbors.

For the remaining grapevines in the area, sever all
vines near ground line that are attached to the tree
crowns other than those inside the arbors. Also,
cut grapevines in the crowns of trees surrounding
the arbor openings.

Herbicide applications as suggested for stands
where a harvest cut is planned in 4 or more years
are effective control treatments; however, it is not
necessary to apply herbicide to vine layers.

3. Young Immature Stands Using Even-Age Silviculture
and Management Practices

11


b. Group selection
Zero to 3 years before the harvest cut.

Retain wild grapevine arbors within the stand.
For the proposed group openings, basal spray
herbicides on the lower 12 to 18 inches of the
grapevine stem and root collar on uncut grape-
vines attached to the tree crowns before cut-
ting. Also, apply herbicide to the layered vines
along the ground surface. Do not treat grape-
vines inside arbors. Basal spraying with 2,4-D;
2,4-DP in oil provides good results. If a basal
spray cannot be used, cut grapevines and
spray the cut stump surface with Roundup
(20-percent solution) or Tordon 101R as pur-
chased. Roundup and Tordon 101R are effec-
tive primarily when the grapevines are not
bleeding sap (late winter, early spring, fall).

For the remaining stand, sever or basal spray
the grapevines.

Four or more years before the harvest cut.
Retain wild grapevine arbors.
For the remaining stand including any desig-
nated group openings, sever or basal spray
vines near ground line that are attached to the
tree crowns. This includes all vines in tree
crowns other than those trees inside grapevine
arbors.

These guidelines will help the forest managers make
decisions on controlling growth of wild grapevines and at
the same time satisfy wildlife and timber objectives in a
managed stand or forest.


Forest Management Guidelines
for Controlling Wild Grapevines

Contents

Growth and Reproductive Characteristics .........0.0..0.0ccceccec cues 1

Growth ..
Flowering
Seed production

Grapevine Control in Forest Management ....

Herbicides

Mature stands—uneven-age management (other partial cuts). 7
Mature stands—even-age management........ 7
Young immature stands—even-age management. . 9
Summary and Management Recommendations ................0ce0000- 1

Literature Cited


The Author

H. Clay Smith is Project Leader of timber management research, USDA
Forest Service, Northeastern Forest Experiment Station, Timber and Water-
shed Laboratory, Parsons, West Virginia. He received degrees from West
Virginia University and Purdue University, and has been engaged in timber
management research with the USDA Forest Service since 1962.

Manuscript received for
publication 20 January 1984

Abstract

Grapevines ( Vitis spp.) are becoming a major problem for forest managers
in the Appalachians, especially when clearcutting is done. on highly productive
hardwood sites. Grapevines can reduce tree quality and growth, and eventually
kill the tree. Silvical characteristics of grapevines are discussed. Forest man-
agement guidelines are given for controlling growth of grapevines. The control
guidelines are applied to mature and immature stands using herbicides and
mechanical treatments. The grapevine-arbor concept is suggested as a means
of regulating the control treatments for timber and wildlife interests.



Young Immature Stands—Even-age
Management

Of major interest to forest man-
agers is grapevine management in
stands after clearcutting practices. If
grapevines are present before clear-
cutting, a grapevine treatment usually
will be needed in the regenerated
stand during the first 10-year period
after clearcutting. In my opinion,
any herbicide or mechanical grape-
vine control measure applied before
clearcutting will not eliminate post-
clearcutting treatments, though the
regenerated stand will have fewer
vines as a result of a prelogging
treatment. We have not evaluated the
influence of the prescribed burning.

Number of grapevines pe acre in
young immature stands was related

to number of man-hours to cut grape-
vines, number of trees per acre with
grapevines present in tree crowns,
and percent of the stand with grape-
vines (Table 2). These data were sum-
marized from surveys of even-aged
hardwood stands 10 to 15 years after
clearcutting, and the stands had
never received a previous grapevine
control treatment. Young stands
averaging 10 grapevines per acre had
about 60 trees per acre with grape-
vines in the crowns. These 60 trees
represent about 3 percent of the
stand based on 1,900 stems per acre
1.0 inch dbh and larger. Young stands
with 300 grapevines per acre aver-
aged about 480 trees with grapevines
in crowns, indicating that about 25
percent of the stand is vulnerable to
some reduction in tree quality due to

Table 2.—Number of man-hours per acre to cut grapevines
and trees with grapevines in the crowns

(immature stands).

Grapevines Man-hours/acre to cut ‘
per acre grapevines Trees with grapevines in crown
No./acre Percent of stand?

10 0.70 60 3

25 78 81 4

50 90 117 6

100 1.15 189 10
150 1.40 262 14
200 1.65 334 18
250 1,90 406 21
300 2.15 478 25
400 2.65 623 33
500 3.15 767 40
600 3.65 912 48
700 4.15 1,056 56
800 4.65 1,200 63
900 5.15 1,345 71
1,000 5.65 1,489 78
1,100 6.15 1,634 86
1,200 6.65 1,778 94

@Stand data at the time of the grapevine cutting treatment indicated an
average of about 1,900 trees per acre 1.0 inch dbh and larger.

grapevines. Of course, not all trees
with grapevines in the crowns will be
appreciably damaged and conversely,
grapevine damage could be so severe
that the tree dies.

It is difficult to determine the
minimum amount of vines per acre
that creates a significant problem
in the reduction of timber quality.
However, | suggest that forest man-
agers use the grapevines per acre/
grapevines-crown relationship sum-
marized in Table 2. For example, a
forest manager may decide that all
areas would need grapevine control
treatment if more than 5 percent of
the trees (40 grapevines per acre) had
grapevines in the crowns.


If a forest manager decided to apply a grapevine con-
trol treatment to a stand when 5 percent of the trees
had grapevines in the crowns (managers can use any
percent so desired as discussed in Table 2), then

about 40 grapevines per acre would indicate a grape-
vine control treatment is needed. Thus, using 40 grape-
vines per acre, the following would be applicable.

a, Commercial-size stands to be thinned.

Stands with less than 40 grapevines per acre.
Retain wild grapevine arbors.
Do not apply grapevine contro! methods.

Stands with 40 or more grapevines per acre.
Retain wild grapevine arbors.
Cut all grapevines near ground line that are
attached to the tree crown other than those
vines inside the arbor. Herbicide applications
are not necessary because overstory crown
shading will control the sprouting grapevine
stumps.

b. Precommercial-size stands.

12

Stands with less than 40 grapevines per acre.
Retain wild grapevine arbors.
Do not apply grapevine control methods.

Stands with 40 or more grapevines per acre.
Delay any grapevine contro! treatments until
the stands have developed a fully closed can-
opy. Shading is the key to controlling the
grapevines. Usually grapevine control treat-
ment can begin when the codominant trees
in the fully stocked stand are at least 15 feet
tall, approximately 8 to 10 years after the har-
vest cut—when one can easily walk under the
tree crowns.

Retain wild grapevine arbors.

Cut all grapevines near ground line that are
attached to the tree crowns other than those
vines inside the arbors. Also, sever all grape-
vines in the crowns of trees surrounding the
arbor openings. Try to apply the grapevine
cutting control measures during the dormant
season and ideally with a few inches of snow
on the ground. If done at this time, a good cut-
ting crew will miss only about 5 percent of the
vines.

Application of herbicides is not necessary
because crown shading will control the vines.

c. Grapevines in stand, but no distinguishable arbor.

Stands with 40 grapevines per acre or less.
Apply no grapevine control measures.

Stands with 40 or more grapevines per acre.
Select concentrated groups of grapevines in
tree crowns representing a desired percent of
the area (example 5 percent). Do not treat
these selected vines during application of a
grapevine control treatment to the rest of the
stand. Trees could be felled to speed up arbor
development.

Cut all remaining grapevines in the stand near
ground line where the vines are attached to the
tree crown using the cutting technique de-
scribed in 3b. Herbicides are effective but not
necessary.

d. Crop-tree release.

In precommercial-size stands with grapevine
problems, delay crop-tree release about 4 to 5
years after a grapevine control treatment. Shad-
ing kills the grapevine stump sprouts and if a
heavy release and grapevine control cutting are
done simultaneously, grapevine sprouting could
be stimulated by the treatment. This recom-
mendation also depends on the average height
of the trees in the stand or whether herbicides
are used. As trees become taller and shading
increases, the delay of releasing crop trees after
a grapevine treatment becomes less important.
Also, herbicides could be applied to the grape-
vines during a crop-tree release treatment; how-
ever, an herbicide control treatment could risk
mortality to some of the crop trees.

4. Uneven-Age Silviculture and Management Practices

a, Individual-tree selection and other partial cuts.

Retain wild grapevine arbors.

Because tolerant species will eventually domi-
nate the stand, grapevine control measures are
optional and can be examined on a stand-by-
stand basis. Other than in the arbors, once the
grapevines are cut near ground level in a stand

managed with the selection cutting practice, the

vines will not return.