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New Zealand Flatworm.


When we moved to Scotland two and a half years ago we noticed a lack of earth worms. One day I noticed what I thought was a New Zealand Flatworm… the first of many. I contacted The James Hutton Institute at Dundee, sending them a live sample and I regret to say my fears were correct. They really are quite horrible ( the worms, not the people in Dundee) and as far as I know hard to get rid of… even the birds refuse to eat them. Anyone else got the same N.Z. Flatworm problem? We live in the little coastal village of Rhu near Helensburgh in Argyll. Our garden soil is heavy clay and we see very few garden worms. Sigh!

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The good news is that early fears of earthworm annihilation have not been confirmed as there is clear evidence that they have found a balanced coexistence.
I found this at Scottish Crop Research Institute:
The New Zealand flatworm (Arthurdendyus triangulatus sensu Jones & Gerard, 1999), was first recorded in the UK in Belfast (1963) and shortly afterwards in Edinburgh (1965), but is now widely distributed throughout much of Scotland, Northern Ireland and, to a lesser extent northern England (Cannon et al., 1999). In Scotland, A. triangulatus occurs predominantly in botanical and domestic gardens, and currently is not generally considered to be a problem on agricultural land. In Northern Ireland it is found in domestic gardens but also appears to have colonized grass leys in many localities.

However, its impact on earthworm populations remains ambiguous, with evidence of numbers in areas with large NZF populations being reduced temporarily before recovering to levels recorded prior to invasion. Other studies have suggested a differential susceptibility of earthworm species to A. triangulatus predation, with recovering populations exhibiting an altered species profile. Results of a large-scale survey of earthworms and A. triangulatus populations in grass fields in Northern Ireland has shown a marked increase in occurrence of NZF's, particularly in field margins

9 Sep, 2012


Many thanks for this information. The people in Dundee did not mention anything one way or another regarding the situation when you have N.Z. Flatworm in your garden. It would be nice to think we can improve our soil over time (it really is poor, a shame when the garden we left was so good to work with, by the time we moved) and hopefully earthworms will increase.

9 Sep, 2012


It does take for ever to improve soil doesnt it, we have been here 15 years next month and in parts of the garden the soil is still very poor despite all that I add every year. I find making compost and leaf mould helps a lot.

9 Sep, 2012


We have eight compost bins and room for making leaf mould... if only in black bags. It all helps!
Loved looking at your photos and bloggs. I too love the nature around me. Chemicals are a no-no and now we can usually find a safer alternative. I am a big fan of Nematodes and also go out with a torch and collect slugs/snails. We tried 'mobactor'(sp) to fight the moss on our biggest lawn and it has helped a lot. Plus it's no longer in the shade of two large oak trees we had to have felled. (mixed feelings about that) but we are trying to make up doing this by helping out the wildlife/insects in other ways. Very expensive having the tree surgeons in as we didn't expect that when we moved in. This means money that was put aside for improving my garden in other ways went on that. Not deterred... I can multiply the plants that I do have by seeds,cuttings and splitting (and swopping with friends) and although it will take longer we will still end up with a lovely garden. That's if we win the battle of the slugs!

9 Sep, 2012


The trees going is sad but think of the water your garden plants will now get and the light. I get lots of plants and bulbs from papers/magazines this last 3 months I have ordered free 180 bulbs 24 pansies 44 Lavender, 36 Penstemon. 3 bearded Iris. Well worth keeping an eye on the press and on here.
I will have some Hollyhock and Yellow Iris seed also a Bidens, Jacob's ladder and Verbina bonariensis self seeded plants shortly if you would like them? Just send me your address in a pm.

9 Sep, 2012


We have flat worms in our village and garden, Hannah, but also many earth worms. The story goes that they came into the village via a lady botanist who often had plant material sent over from NZ. They are nasty looking things but I don't believe that they really do harm.

9 Sep, 2012


Hello Bulbaholic. It is amazing just how many people have N.Z.Flatworm in or near their own gardens. It is a knee-jerk reaction when you get something new, to panic at first. So many new pests are coming into our country... we read about them so often. It's encouraging they may not be the problem we first thought.

10 Sep, 2012


Hello again Drc726. The papers and magazines do seem to have good offers. I too will keep my eye out for them.
I picked up a sad little Passiflora plant (still labelled) in a local garden centre for 50p. People were looking at it with distain but I brought it home, potted it on and cut it right back. I am so pleased I did as it's made a lovely plant that is going from strength to strength.
Regarding your kind offer... thank you so much. I will indeed message you my address. Once my garden gets established I like to think we will have something useful for your garden.

10 Sep, 2012

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