Tag Archives: pests

Our New Zealand Flatworm Problem

We have just received the interim report from OPAL and the University of Aberdeen on our flatworm problem.  It does not make for great reading as it suggests that over 70% of our plots are infested with these pests.

Suggestions as to how to deal with flatworms, taken from this very helpful report, has been incorporated into a new page under the Advice and Support tab above.  You will also find a copy of the interim report.

New Zealand Flatworm Survey

The University of Aberdeen are conducting a survey of NZ Flatworms and are looking for a number of allotment holders to participate, both those with and without NZ Flatworms and would appreciate answers to the following questions

1. Do you have New Zealand Flatworm on your plot at present?
2. Have you had New Zealand Flatworm on you plot historically?
3. Would you be happy for someone from Aberdeen University to visit your plot and record presence and abundance of NZ Flatworm, soil pH, take a small soil sample and record earthworm numbers?
In addition they would ideally like to talk to you or alternatively get you to fill in a questionnaire to enable them to gauge the scale of the problem and find out more about your experience of NZ Flatworm. This would be done mid-March- April at a time convenient to you.

4. If you are not able to participate in the study they would really appreciate it if you could fill in this short survey http://www.opalexplorenature.org/nzflatworm Hard copies of the survey can be obtained by contacting Annie Robinson direct at annierobinson@abdn.ac.uk

If you wish to participate please contact Annie as soon as possible. It would be helpful if you would be good enough to let me know if you decide to participate.


New Zealand Flat Worm Study

Thanks go to Bruce Taylor for alerting me to this study.

Aberdeen University has announced it has researchers taking part in a national survey of the New Zealand Flatworm‘s spread and its effects on our gardens, plots and fields.

2015-06-12 at 08.59

As we know the Flatworms kill our native earthworms, but the university site contains some truly gruesome details about how they go about their murdersome business and how difficult they are to eradicate once they get established. It appears that the flatworms can reduce to 10%  of their body weight for up to a year as they await another earthworm dinner.  Perhaps the weight-loss industry ought to be sponsoring this survey!

More details, including how you can participate, are available via these links:

Aberdeen University Research Press Release

National Flatworm Research Project

Unwelcome Visitors to Garthdee Field

Bare Faced Cheek!

I had noticed for a few weeks that something or somebody was chomping its way through the remains of my chard, but late this afternoon we arrived in time to catch the culprit in the act.


He/She stood her ground for a few moments before showing off her effortless hurdling skills over the fences between the plots: I finally caught this photo as she arrived at Michael’s plot up by the railway line.

Can anyone throw any light on the species and gender?

Unwelcome Visitors

The NZ flatworm

The NZ flatworm

Stuart recently circulated an email reminding us that New Zealand flatworms have been resident on our site for several years now.  If you are lucky enough not to have come across any on your plot, you want to look out for them – they are a murderous bunch and live almost exclusively on our native earthworms.

Some of our plotters report finding no earthworms in their soil for the last four years or more and NZ flatworms (Arthurdendyus triangulates) are the obvious suspects. They kill their smaller earthworm prey in the most unpleasant way – covering them in mucus to part-digest them, then sucking up their remains. They have a voracious appetite and will quickly decimate local earthworm communities if left uncontrolled.

Know your enemy

Know your enemy

They are not a problem limited to our area. Researchers from Scottish Natural Heritage indicate they are present across much of Scotland as this Advice Note and Distribution Map shows. Early reports from the 1960s, when they first appeared in the UK, warned of the possible elimination of our earthworm populations, but more recently commentators have suggested that with help our earthworms may be able to come to terms with the interlopers. Research is on-going at The James Hutton Institute and sightings should be reported to Dr Brian Boag via the above link.

Control Measures

Can we fight back? Unfortunately, it seems that once established the New Zealand flatworm cannot be eradicated: however, their local impact can be reduced to a degree. The following methods are suggested:

  1. Inspect any pots or containers of bought or swapped plants before planting to prevent new infestations.
  2. Look under flat stones or wood etc. as the flatworms retreat to these locations during the heat of the day.
  3. Lay such traps, or peg out sacking to find if they are present.
  4. Kill any flatworms found by grinding between stones, completely squashing, dropping them into very salty water or spraying them with lemon juice.
  5. Ground and Rove Beetles are reported to prey on the adults.
  6. Add farmyard manure to help introduce more earthworms.
Bruce on flatworm patrol

Bruce on flatworm patrol

Need more information?

Pat Wilson circulated a recent Factsheet – see Stuart’s email.

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