Transcript Ailanthus altissima - Natural Resources Class 2013

Ailanthus altissima
Ailanthus altissima
• Family:
Simaroubaceae
• (sim-a-roo-bA-C-A)
• Native to: China
Common Name
Ailanthus altissima
Common Name
Tree Of Heaven
Ailanthus altissima
AKA
Ailanthus
Chinese Sumac
ECOLOGICAL IMPACTS:
• Uses lots of
water
• Increases
soil pH
• Decreases
C/N ratio
• Changes
habitats –
converts
native
vegetation
stands,
particularly
riparian
habitat
Affected Areas - N America
Source: USDA
Invasive Status in Europe
National Register of
Big Trees
•
•
•
•
•
•
•
•
Location: Westmoreland, VA
Circumference: 244”
Height: 55 feet
Spread: 48 feet
Points: 311
Year Nominated: 2009
Nominator/s:
Carmean, Williamson,
Wilson, VA
Plant ID
• Leaves
compound 18-24'' long
with 13-25 leaflets
arranged alternately on
stem, lanceolate, 3-5''
long with 2-4 teeth near
base.
• Twigs
reddish-brown with a
distinctive leaf scar
Ailanthus altissima
FLOWERS
• Panicles, 8-16'' long,
yellowish-green, mid-June
• Dioecious (male and
female flowers on
separate plants
• A fragrance that “could
chase people out of the
garden” gives it its
derisive nicknames of
"ghetto palm" and "stink
tree".
Fruits
• Samara,
furrowed
winged
seed
cluster
• seeds
not very
nutritious
for (and
therefore
not very
attractive
to)
animals
INVASIVE ADVANTAGE:
•A. altissima is a "classic weed" species (Stobel, 1991)
Allelopathy
• can suppress
competition from
other plants
(particularly natives)
with allelopathic
chemicals
• Its leaves are toxic to
over 40 native
species of plants.
Resource Availability
• modifies nutrient
cycle; leaves
decompose at much
faster rates than
native species
Competition
• Can grow up to 1m
per year, outcompeting native
seedlings.
• Has the ability to
quickly colonize
disturbed areas.
• Very fast growing,
dense canopy shades
out native species.
Escape from Biotic Constraints
• in China it had 30
natural predators,
here, not so much.
• Here, no large
animals eat it, it is
unpalatable to
herbivores.
• Reportedly NOT A
host of Asian Longhorned Beetle (ALB)
Habitat:
• Highly adaptable and
pollution tolerant, grows
in the poorest of soils, in
full sun to partial shade.
• It does not grow well is
full shade or in flooded
conditions.
• Ailanthus can overwinter
in northern climates, and
is resistant to both frost
and drought, giving it a
clear competitive edge
over native species.
Spread
• Reproduces sexually and
vegetatively.
• Prolific seeder; One study
reports that an individual tree
can produce as many as
325,000 seeds per year.
• Seeds are wind dispersed
easily, often taking advantage
of the wind-tunnel effect of
roadways. Seeds can hang out
on tree all winter.
• Germinate with as little as 3%
light cue.
• The plant also spreads by
aggressive suckers, or
runners. Re-sprouts vigorously
from cut stumps.
Because of these attributes, Pennsylvania state
botanists have dubbed A. altissima
Tree of Hell
NON-CHEMICAL CONTROLS:
Integrated Vegetation
Management (IVM)
cultural
manual
biological
CULTURAL
• Prohibition
• CT – invasive –
banned
• MA – prohibited
• NH – prohibited
invasive species
• VT – Class B noxious
Weed
CULTURAL
• Remove as much Tree of Heaven (ToH) without
disturbing other vegetation, to slow down
regrowth of ToH
• Competitive ground cover to retard re-growth
(eg crownvetch)
• “Any method must be diligently and continuously
pursued to eradicate this invasive weed. For the
occasional stubborn individual tree, the Division
of Forestry recommends flame-throwers and
bulldozers as a means of permanent removal.
Burning doesn’t work unless you get the whole
root, which generally is not the case.”
MECHANICAL
• Young seedlings may be pulled or dug up, preferably when soil is
moist. Care must be taken to remove the entire plant including all
roots and fragments, as these will almost certainly regrow.
• Cutting alone is usually counter-productive because Ailanthus
responds by producing large numbers of stump sprouts and root
suckers. However, for small infestations, repeated cutting of sprouts
over time can exhaust the plants reserves and may be successful if
continued for many years or where heavy shade exists.
• If possible, the initial cutting should be in early summer in order to
impact the tree when its root reserves are lowest. A Subsequent
cutting late in the season removes stores to support it in winter.
Mow new shoots from cut trees regularly for several years to
gradually weaken root systems. Cutting large seed producing female
trees would at least temporarily reduce spread by this method.
BIOLOGICAL
• Natural control methods are limited. The tree of heaven
is preyed upon by very few insects due to the chemicals
in its wood and bark.
• The fungus Verticillium albo-antrum kills A. altissima, but
unfortunately the fungus spores remain in the area of the
dead tree and will kill many species of native trees that
might germinate in the infected location.
• Several fungal pathogens are being investigated as
potential biological controls for ailanthus. Two of these,
Verticillium dahliae and Fusarium oxysporum, have been
isolated from dead and dying ailanthus trees in New York
and in southern and western Virginia. A disease affecting
ailanthus in PA was studied using inoculations in the lab
and on canopy field trees; the agent was identified to be
Verticillium albo-atrumand.
CHEMICAL CONTROL
• Gets fully 2/3 of any research article‘s publication space
allotment for control measures.
• The most effective method of ailanthus control seems to
be through the use of herbicides, which may be applied
as a foliar spray (to the leaves), basal bark, cut stump, or
hack and squirt treatment.
• Keep in mind that it is relatively easy to kill the above
ground portion of ailanthus trees, you need to kill or
seriously damage the root system to prevent or limit
stump sprouting and root suckering.
• Always be extremely careful with herbicide applications
in the vicinity of valuable ornamental shrubs and trees.
SOURCES / REFERENCES
•
•
•
•
•
•
•
•
•
•
Isolation and characterization of seed germination inhibitors from ailanthus
altissima, Lisa McFarland, Univ Maine Orono MS Chemistry Thesis, 1996
VT Exotic Invasive Species Fact Sheet Series VT Fish & Wildlife
Dept of Environmental Protection, VT, Invasive Plant Information Sheet
Ailanthus altissima
Schall, M.J. and D.D. Davis. 2009. Verticillium wilt of Ailanthus altissima:
susceptibility of associated tree species. Plant Disease 93:1158-1162.
Managing Tree of Heaven on Roadsides Penn State Dept of Horticulture
Fact Sheet
Jil M. Swearingen, National Park Service, Center for Urban Ecology,
Washington, DC
Powerpoint presentation, Univ of Nevada, Reno
Texasinvasives.org
Alien Invasive Species of VA – VA Dept of Conservation & Recreation
Pacific Island Ecosystems at Risk (PIER)