(snip, lots of interesting stuff)
bottom of a platic plantpot? (this is where people keep telling me they
What do they look like, Kathryn?
Diane Ridout, Instructor, ACP.............................................
Kwantlen University College, "Talk
12666-72 Avenue doesn't
Surrey, BC, Canada V3W 2M8 cook rice," they say.
Tel: (604) 599-2964 Voice mail 9837.......................................
Cook Organic Garden Club wrote:
Snip
> I fear I have to admit this horrendous killer is a New Zealand native.
> I'm sure nobody will hold it against you! Would you happen to know its > systematic name?
Loren
I had to go to the guru at the National Museum for this information and
he not only gave me the name, but also sent me copies of some relevent
literature.
The NZ species, which got into Britain (specifically Scotland) in the
60s is (hold your breath!) Artioposthia triangulata. It exhausts me
just to spell it. An Australian species Caenoplana alba seems to have
arrived about the same time.
A few facts from the reprints. Although the NZ species is now well known
and already a serious pest in Ireland and Scotland and even in the
remote Faeroe Islands (Between the Shetlands and Iceland) and found
once in a glasshouse in Iceland itself, there has only been one sighting
in England (at Carlisle) and one in the Isle of Man. It is apparently
unlikely to spread further south, as it dies at temperatures above 20C.
This is no doubt why in its native country it remains confined to cool
southern forests and has not spread into cultivated areas.
It says very little about the Australian species, which would almost
certainly be able to withstand higher temperatures, beyond saying it
occurs in SW England.
Artioposthia probably travelled as eggs in a potted plant being exported
from NZ. (this trade is no longer allowed). It seems to have reached
Scotland first and was unearthed in Edinburgh's Royal Botanic Gardens in
1965. It is now very common in gardens in Edinburgh and its
neighbourhood and is present through much of the rest of Scotland. They
surmise the spread as starting with the Botanic Gardens and going thence
to plant nurseries and garden centres and so on to private gardens. (and
also over the sea to Ireland).
Up till now there has been been very little penetration into farm land,
because there is not much exchange of soil between gardens and
agricultural land. However it may be only a matter of time. Ironically,
the writer comments that because arable farmers rely more on fertilizers
than natural fertility, the loss of earthworms may not affect them as
much as the gardeners (Organic farmers take note!) However, it will
certainly be serious where land is under permanent pasture.
There is a grusome description of how the pest operates. Apparently
flatworms are shape changers (shades of SciFi) and can make themselves
long and thin to pursue their prey down their burrows. When one catches
up with a worm it wraps itelf round the unfortunate creature and
secretes digestive juices after which "it sips its liquidised victim
through a sli-like mouth on the underside". (Charming, eh)
They seem to have a tremendous appetite. At 10C they are estimated to
eat 14 worms a week. At that rate 6-7 flatworms under a square metre of
soil might take only a year to consume the approx. 470 eartheworms
inhabiting such a patch. Once the earthworm population is heavily
reduced one might expect the population of the predator to drop also
until an equilibrium is reached. Unfortunately, this does not happen
because if there is no food around a flatworm can survive up to a year
without eating.
THe prognosis is not good for infested areas and I did not see any
indication that anybody has come up with an effective control.
As you can imagine, the cooler countries of Europe, especially
Scandinavia are very anxious not to acquire this unwelcome visitor and
are putting in place various controls which they hope will keep it out.
And that's all I can find out
Moira
--
Tony & Moira Ryan
Both Retired. Careers were: Moira - botanist/horticulturist;
Tony - Various jobs, then computer programmer.
Wainuiomata, Lower Hutt, New Zealand
I have doubts about the date of its arrival in Ireland and suspect it has
been around considerably longer and may have arrived at one of the
nurseries in Northern Ireland which specialised in NZ introductions as much
as 50 or 60 years ago. I heard yesterday of one organic farmer in the irish
midlands who has had it for over 20 years and who nonetheless has a
thriving earthworm population. He puts it down to breeding earthworms
faster than the flatworms can eat them and also to predation on the young
by ground beetles and centipedes. Another friend with a tiny garden only
about 6 yards square has been killing 2-3 a day for a year in one corner
without them apparently spreading to the rest of the garden (and now I
think of it the rest of her garden is warm and sunny). Do you know what the
most efficient method of killing it is when you find one curled up in the
bottom of a platic plantpot? (this is where people keep telling me they
find them) And do they regenerate if attacked with a pair of scissors -
I've heard of a few people doing this. If anyone does find one - get it
quickly, until you have seen one move you wouldn't believe how fast it can
go.
Happy hunting
kathryn
I posted to either this list or the sqft list that I believed I had found some
type of flatworm in my U.S. garden. I have not seen any this year in my
northeast Pennsylvania garden, however, I believe in the past I didn't see them
until June. I found them curled up under stones and boards I had actually
scattered around for slug traps. They looked very much like those described and
pictured on a web site suggested by someone on the list. I mashed them
completely. I haven't noticed an earthworm population decrease, but, the
flatworms have decreased in numbers over the last three years. I probably only
killed three or four total last year compared to maybe 20-24 three years ago
(garden is 12'X14'). I have noticed a marked population increase in what I
believe is a centipede, which someone mentioned may be a predator. I'll try to
keep the list posted as to whether they show up this year. They sound like a
pretty nasty pest.
Henry
kathryn marsh wrote:
Diane
They vary in colour from sort of dried out liver brown to lightish liver
brown fading to paler brown, pinkish, or dried blood at the edges - always
lighter at the edges. The biggest I've seen would be about 6 inches long
straightened out and around 1/4 inch across. You find them curled around
in a flat spiral with a sluglike mucus around them and often a half
digested earthworm in the vicinity. I've also seen half digested slugs so
maybe they eat those as well.To move they straighten fast, develope a sharp
point at one end and take off very quickly. Adrian would have a really good
description since he has the misfortune of living with them full time
kathryn
For picture of N Z flatworms try
http://www.nwl.ac.uk/ih/prototype/research/flatworm.html
Adrian
adrian.saunders@dnet.co.uk
Date: 18 May 1998 22:25
Subject: Re: evil flatworms
always
> lighter at the edges. The biggest I've seen would be about 6 inches long
> straightened out and around 1/4 inch across. You find them curled around
> in a flat spiral with a sluglike mucus around them and often a half
> digested earthworm in the vicinity. I've also seen half digested slugs so
> maybe they eat those as well.To move they straighten fast, develope a
sharp
> point at one end and take off very quickly. Adrian would have a really
good
Diane Ridout wrote:
Diane
Just a wild guess, but this sounds to me like a large centipede.
I fear I have got pretty behind with my mail, so probably this won't be
much use to you!
Moira
Tony & Moira Ryan
Both Retired. Careers were: Moira - botanist/horticulturist;
Tony - Various jobs, then computer programmer.
Wainuiomata, Lower Hutt, New Zealand
Yes, that's what I figure it is--except that size isn't "large" for the
ones here, it's average! (If they are plant eaters...oh my.)
Now for a question that might be useful to people other than me:
centipedes and millipedes--what do they eat? I vaguely recall that one is
beneficial and one can be harmful, but I don't remember. (I don't worry
too much about bugs or whatnot, except for the slimey hordes, of
course.)
Diane Ridout, Instructor, ACP.............................................
Kwantlen University College, "Talk
12666-72 Avenue doesn't
Surrey, BC, Canada V3W 2M8 cook rice," they say.
Tel: (604) 599-2964 Voice mail 9837.......................................
Some 8 year old insect loving type around here has walked off with my
general field guides, but partly from memory and partly from
gardening insect books. Centipedes eat insects spiders and snails.
Their legs are really obvious long legs sticking out to the side.
About an inch and a half, maybe two inches is the longest centipede
I've ever seen, and the only ones I've seen have been light to dark
brown. They are very fast.
Millepedes feed mostly on rotting vegetation but "may attack any
small or tender plants" usually feeding on plant parts in "contact
with the soil or close to the ground." It's not usually necessary to
control them unless populations are unusually high.
I've seen millipedes that I would swear are three to four inches
long. Their legs are directly under their body, and hard to see on
first look. The ones I have seen have been dark grey to black. I
have only ever seen them in woodland areas. They are fairly slow
moving.
My bet is that what you have is neither a millipede nor a centipede,
but I don't know what it would be.
sph (yes it is still me although the email address has changed)
Sandra P. Hoffman
ghidra@igs.net
http://www.flora.org/sandra/
(snip)
> My bet is that what you have is neither a millipede nor a centipede,
> but I don't know what it would be.
Uh-oh! But, well, I *kinda* think it is a millipede--it looks like the
picture I saw, and the descriptions I've read. Maybe I was mistaken, and
it was not chasing the earthworm, or maybe they were playing tag (or maybe
I'm in denial!). Thanks for the help.
Diane Ridout, Instructor, ACP.............................................
Kwantlen University College, "Talk
12666-72 Avenue doesn't
Surrey, BC, Canada V3W 2M8 cook rice," they say.
Tel: (604) 599-2964 Voice mail 9837.......................................
