I have just been reading about the light brown apple moth, which has just been found in the California Bay Area. I am wondering if there are members from other continents who have any experience with this pest?
It seems to eat everything (well 250 species, in many plant families). It is from S.E. Australia. I wonder if it has moved to mediterranean parts of that continent or other mediterranean areas? The article in yesterday's Chronicle (Business Section, for California members--you can read the article on sfgate.com) says it has invaded New Zealand, Ireland, the United Kingdom, and Hawaii. From the Web, I think maybe it is in Europe too?
My question is whether any members live in areas where it has invaded, and, if so, is it as awful as it sounds? What is done locally to manage it?
Thanks,
Pam Peirce
San Francisco, CA
I don't know if my experience with light brown apple moth is relevant as =
like plants out of place, pests out of place seem to behave differently, =
but here goes. Here in their natural habitat, I find they are a seasonal =
pest of spring and occasionally autumn, and they seem to have a very =
narrow temperature range. Once it heats up or gets cool they disappear. =
They seem to last a week or two twice a year. They are destructive of =
new growth but of established plants, trees a year or two old, not =
seedlings. They prefer what used to be called eucalypts. Rarely do they =
do so much damage that the tree is compromised but if an infestation is =
followed by any adverse event then the tree may die. A bad infestation =
does seem to weaken a plant in ways that are not obvious. Treating them =
seems to be a waste of time here as the climate usually takes care of =
them and they seem unresponsive to everything except plunging the =
beggers in hot water and screaming 'die you demons, die'. I am curious =
as to what you are being threatened with by way of the consequences of =
their arrival, because, as I mentioned they are a minor problem here =
rather than one of those things that make me think lovingly of concrete =
and parking lots.
Margaret Healey
Near Ballarat
----- Original Message -----
From: p.k.peirce@att.net
To: medit-plants@ucdavis.edu
Sent: Saturday, April 07, 2007 4:49 AM
Subject: Light Brown Apple Moth
I have just been reading about the light brown apple moth, which has =
just been found in the California Bay Area. I am wondering if there are =
members from other continents who have any experience with this pest?
It seems to eat everything (well 250 species, in many plant families). =
It is from S.E. Australia. I wonder if it has moved to mediterranean =
parts of that continent or other mediterranean areas? The article in =
yesterday's Chronicle (Business Section, for California members--you can =
read the article on sfgate.com) says it has invaded New Zealand, =
Ireland, the United Kingdom, and Hawaii. From the Web, I think maybe it =
is in Europe too?
My question is whether any members live in areas where it has invaded, =
and, if so, is it as awful as it sounds? What is done locally to manage =
it?
Thanks,
Pam Peirce
San Francisco, CA
Here in California they are unlikely to be held in
check by their natural predators (since those species
don't likely live here), and if the LBAM is active
during certain times of certain temperature ranges,
the possibility exists that in our milder coastal
regions they would remain active for much longer than
in habitat.
There's no telling how an exotic species will perform
out of its natural context.
Jason Dewees
San Francisco
--- khe36747
The place to find evidence of the moth would be the caterpillar/cocoon,
in rolled up leaves.
Richard Starkeson
San Francicso
who has not yet seen one, although they have been recorded here.
In discussions with friends who are fruit growers we find that climate =
is the greatest 'predator' of the moth in this area. However the NSW ag =
dept suggests different climatic conditions to ours in which the beastie =
reaches its peak malevolence. We are now wondering if the moth has =
formed different sub species across its range and whether this genetic =
variability/instability is part of its armory as a pest species. In more =
general terms does anyone know if genetic instability is considered to =
be greater in pest species of both plants and animals than in other =
species? Or is just 'out running' their predators their main 'skill' for =
success?
Margaret Healey
This interesting article appeared last month, suggesting that for
plants, at least, genetic variability drives invasive potential.
http://www.sciencedaily.com/releases/2007/02/070227105553.htm
(article is also available online in the PNAS (http://www.pnas.org/)
Early Edition, and will be published March 6, 2007, in the journal's
print edition.)
Science Daily - Reed canarygrass is a bit like some people on
vacation. At home, they stay on their side of the fence, and speak
nicely with the neighbors. But jet them into Las Vegas and by week's
end they are shoving other people out of the way in the casino.
Similarly, the reed canarygrass is well-settled in its native
European range, not pushing out other species or expanding its
terrain. But strains introduced into the United States are running
amok ecologically, choking out native plants in wetlands-including in
Vermont. Once praised as a fine forage crop, the grass is now
considered an invasive pest in at least three states and its range is
growing.
Studying this grass as a model, Jane Molofsky, associate professor of
plant biology at the University of Vermont and her post-doctoral
associate, Sebastien Lavergne, have discovered a novel mechanism to
explain the surprising conversion of some plant species from quiet
neighbor at home into expansive bully in new territory.
As they report in a forthcoming edition of the Proceedings of the
National Academy of Sciences the invasive power of this grass,
brought to America in the mid-19th century and many times thereafter
comes not from any one individual plant, but from this history of
multiple introductions from different regions of Europe.
"It's not that you're taking the ones in France and moving them to
the US and they're suddenly invasive," Molofsky said, looking over a
green swath of reed canarygrass growing in a UVM greenhouse, "its
that you move some plants, and then you move some from somewhere else
and they recombine here to form something better, genetic superstars."
The result: in America, reed canarygrass has developed traits, like
faster emergence in the spring and larger root biomass, that allow it
to become a rapid colonizer. In short, the grass is still the same
species, but it has quickly evolved to be invasive.
And this has significance far beyond the headache of reed
canarygrass. A noteworthy "implication of our paper is that not only
do invasive species evolve but we show that they can evolve extremely
rapidly," notes Sebastian Lavergne, now at the University of Grenoble
in France, striking a blow at the conventional view that evolution
occurs at very slow rates.
Molofsky's greenhouse- and field-based study, funded by the US
Department of Agriculture, shows why. Thanks to a large network of
European collaborators, she and her students collected plants from
both the center and edge of the native range in Europe, getting
individuals from southern France and the Czech Republic. They also
collected from the invasive range center in Vermont and the edge in
North Carolina.
They discovered that the grass in its native Europe show a typical
decrease of genetic diversity at the edge of the range, constraining
its ability to adapt and expand into new conditions. But in the US
invasive range, they found a different story. There, the invasive
plants thrive on infusions of Europe-wide genetic material, allowing
them to quickly adapt to new conditions and continue their quiet
march into new fields and wetlands.
"The problem is that these invasive species at the range margin are
maintaining most of the genetic diversity which represents a
substrate for future evolution," Molofsky says, "so when climates
begin to change we expect that some individuals from those
populations will be able to grow in new conditions. But it is
unlikely that native species have maintained enough genetic
variability to move with rapid climate changes." Invaders persist,
natives expire.
