| By Maryann Whitman
Invasive and destructive gypsy moths fall prey
to a "fungus among us." Homeowners begin
to realize that their lawns really do
suck (too much water). And does NASA
still go where no one has gone before?
Surprise, surprise
When populations of gypsy moths reach outbreak
proportions, the caterpillars can completely
defoliate host trees over a wide geographic
area. Consistent or repeated defoliation
over several years can have devastating
effects, often leading to tree stress
and death.
Gypsy moths have a wide host-range, which
includes oak (Quercus sp.), crabapple (Malus
sp.), linden (Tilia
sp.), poplar (Populus
sp.), beech (Fagus
sp.), willow (Salix
sp.), birch (Betula
sp.), sweetgum (Liquidambar
styraciflua), serviceberry (Amelanchier
sp.), and hawthorn (Crataegus
sp.). Trees
less-susceptible to attack by gypsy moth
are
ash (Fraxinus sp.), sycamore (Platanus
sp.), indian bean (Catalpa
sp.), honeylocust
(Gleditsia sp.), dogwood (Cornus
sp.),
junipers (Juniperus sp.), yew (Taxus
sp.),
lilac (Syringa sp.), arborvitae (Thuja
sp.), arrowwood (Viburnum
sp.), and tulip
tree (Liriodendron
tulipifera).
Conifers are more susceptible to death
than deciduous trees because they don’t
produce another flush of growth once defoliated.
Conifers, such as pine (Pinus
sp.) and
spruce (Picea sp.), are unable to produce
new leaves (needles) after defoliation
as compared to deciduous trees. As
a result, conifers can die after one severe
defoliation.
The ecological and economic impact
of gypsy moths is a serious concern. Gypsy
moth defoliation can change the complexity
of understory growth thus resulting in
an increase or decrease of certain fauna
or flora. Defoliation may predispose trees
to attack by opportunistic insects or diseases.
For example, Gypsy moth feeding can increase
a tree’s
susceptibility to the attack by the shoestring
fungus, Armillariella mellea and the two-lined
chestnut borer, Agrilus
bilineatus.
While major damage has tended to occur
in the Northeast and Upper Midwest, gypsy
moths are caught in pheromone traps across
the country. This indicates that they are
continually present at low levels
in scattered locations across the United
States.
Native to Asia and Europe, gypsy
moths were accidentally introduced into
the Boston area in 1868 or 1869, (the
fellow thought they might help him make
his fortune in the silk industry – but
that’s another story). Apparently they
were
causing enough damage in the New
England States for desperate measures
to be taken in 1910 and 1911 – a fungus
(Entomophaga maimaiga), known to affect
only Japanese gypsy moths was introduced
in Massachusetts. And then the fungus
disappeared.
New information out of Cornell University,
Department of Entomology confirms that
the fungus is still alive and well. It
surfaced again in 1989, when gypsy moth
larvae were found dying and dropping out
of the trees.
The fungus has had a century of
opportunity, but does not seem to infect
any other Lepidoptera. Now it’s just a
matter of figuring out how to harvest,
reproduce and spread the fungus in the
infested areas.
Lawn Gone: Homeowners rethink
their water-sucking lawns
A “delawning” movement is sprouting
up around the United States, as a handful
of homeowners switch from resource-intensive
grassy green expanses to drought-tolerant,
native, and/or edible gardens.“It’s
about shifting ideas of what’s
beautiful,” says Fritz Haeg, a Los Angeles
architect whose Edible Estates project transforms
front yards into fruit and vegetable gardens. A new
report from the Public Policy Institute of California
provides more fodder for the anti-lawn set. It asserts
that thirsty home landscaping will suck up a troubling
amount of water in the state over the next 25 years
if the love affair with lawns continues. California
is expected to add
11 million new residents by 2030, with
at least 50% settling in hotter inland
regions where single-family homes with lawns are
common, according to the report. Some neighbors,
however, don’t appreciate creative gardening. “What
happens in the backyard is their business,” said
one man who lives near a yard now being
used to grow 195 various edibles. “But
this doesn’t seem to me to be a front yard
kind of
a deal.”
NASA Lapso: NASA deletes planet-protecting
phrasing from mission statement.
The phrase “to understand and protect
our home planet” was quietly deleted from
NASA’s mission statement in February.
The agency’s mission now is “to pioneer
the future in space exploration, scientific
discovery, and aeronautics research.” NASA’s
19,000 employees were neither consulted
nor informed ahead of time of the deletion.
The planet-protection phrase had been added
to the mission statement in 2002. Scientists
say it shaped research priorities, and the deletion
will reduce
incentive for research on phenomena like – oh,
to pick one at random – climate
change.
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“Lawn Gone” and “NASA
Lapso” reprinted
by permission from Grist
Magazine (www.grist.org).
For more environmental news and humor,
sign up
for Grist’s free e-mail service, www.grist.org/signup.
Maryann is Editor of the Wild Ones Journal, and comes to the position with an extensive background in environmental matters of all kinds.
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