Thursday, 17 September 2015

New LeafWatch recording app

New LeafWatch recording app

Today we have launched the new LeafWatch recording app to make taking part in Conker Tree Science easier than ever. See the press release for full details.

Now is the time to look for the horse-chestnut leaf-miner, and these records continue to be really valuable, especially with the discovery of the horse-chestnut leaf-miner in Scotland last September and its recent arrival in Ireland. Records of the moth with help us understand how non-native species species like this spread.

All you need is to download the app (available for Apple on iTunes and for Android at Google Play) and get recording!

Remember that records of the moth's absence are also really valuable - knowing where it has not got to is really important. We are especially interested in records in Scotland and Ireland, and regions away from the south and east of England, but welcome records from anywhere.

However, be careful not to confuse the damage caused by the leaf-miner with the fungal leaf blotch. These are caused by the fungus Guignardia aesculi and the two types of damage are really easy to distinguish:.  
  • Pale blotches, turning brown, and without a yellow ring. It is the leaf-mining moth - each mine fits within the main leaf veins, although mines can merge together if there are lots of them.
  • Brown blotches always with a yellow ring - usually irregularly shaped crossing the main leaf veins. It is the fungal leaf blotch (not the leaf-miner), so let us know it is not the leaf-miner.
  • It can get confusing because the leaf-miner and the fungal blotch can both occur on the same leaf.

We can verify all the records submitted via the app.

Of course, you can still make records via the Conker Tree Science website - all the records via the app and the website are used for research. If you record via the website then you can record the leaf-miner and the fungal leaf blotch separately.

(Some readers of this blog might remember that the original LeafWatch app was first launched in 2011. At that time it was one of the first wildlife recording apps available. However technology moves on and by 2013 the original app did not work on many smartphones. With the continued spread of the leaf-miner we decided to invest in updating the app to make it easy to record its presence. Most of the investment was actually in connecting the app to a better back-end database called Indicia, so that we can verify records much more easily.)

Monday, 3 August 2015

Conker Tree Science in the Guardian

Today the Guardian featured a story about the northward spread of the horse-chestnut leaf-miner and promoted the Conker Tree Science project.

Dr Darren Evans, one of the people behind Conker Tree Science is quoted saying “it’s only a matter of time” before the species expands further north into Scotland. He did know that the moth has just once been confirmed in Scotland (see the latest distribution map) although that fact was lost in the communication. However he later tweeted that "there is a confirmed record of the leaf-mining moth in Scotland. Citizen scientists can help map spread via Conker Tree Science". The big question he was asking though was where it would expand to in Scotland?

Monday, 13 July 2015

Wanted: people interested in recording longhorn beetles

Longhorn beetles
Your chance to get up close to longhorn beetles
(photo: dluogs via Flickr creative commons)

Longhorn beetles (members of the Cerambycidae family of beetles) are a fascinating group of beetles. They are often large, impressive (especially with their long antennae) and many species are of conservation concern because of their dependence on woodland. Some of the species visit flowers as adults, but many species are hard to find because they live as larvae in wood and the adults are quite inconspicuous.

A trial to record longhorn beetles with pheromone lures

We are developing methods of recording longhorn beetles with pheromone lures attracting them to live traps. (One of our motivations is developing a network of recorders for Asian longhorn beetle - more of that below.) We need about 10 volunteers to take part in trials of the lures this summer and who will commit to recording longhorn beetles and providing us with results.

Interested in volunteering?


Please contact Michael Pocock as soon as possible if you are interested in taking part with a brief description of (1) your site of interest, (2) whether landowner permission has been granted or coudl be obtained and (3) your availability this summer. Only a limited number of people can participate in 2015. Please see the note at the bottom of this page about Asian Longhorn Beetle before volunteering.


If you are interested in volunteering, you will need:

  • a woodland site where you can gain permission to live-trap longhorn beetles.
  • the ability to check the traps at least twice per week, preferably every other day for about a month.
  • the ability to photograph beetles in the traps, and try to identify them.
  • commitment to submit all the data collected during the trial.

The benefits of taking part are:

  • we will provide you with all the equipment needed.
  • you will make a contribution to knowledge of longhorn beetles in Britain, and will be able to make records of this fascinating group of insects.
  • you will make a contribution to the development of lures as a method to record longhorn beetles

The methodology will involve:

A longhorn beetle pheremone trap in position
  • finding a woodland site (ideally a woodland clearing or ride in deciduous or mixed woodland) which you will be able to visit regularly during the summer. 
  • gaining permission from the landowner (see the note about Asian longhorn beetle below; also additional permission will need to be gained if the site is a SSSI)
  • receiving the equipment from us through the post
  • hang the trap, lure and collecting jar from a convenient branch of a tree (about head height) along a woodland ride or clearing edge where it is unlikely to be disturbed by passers-by
  • traps need to be in position for a month from the end of July to the end of August, and during that period you will need to visit the trap regularly (ideally daily, and at least twice a week)
  • empty out any longhorn beetles collected, photograph and identify them, and then mark them (with a dot from a marker pen) before release
  • collect up all the equipment at the end of the summer and return to us
We will use the results of this trial to consider whether these lures could be used as an effective way to record longhron beetles and to design a suitable protocol.

An important note about Asian longhorn beetle

The Asian longhorn beetle (ALB) is a destructive pest that has occasionally been introduced to the UK and on one occasion it established a population which has since been eradicated. ALB is established in North America, where it has damaged many species of hardwood trees. If ALB is present, it is really important to detect it as soon as possible, which is why David Hall (Natural Resources Institute) is developing these lures. The byproduct of using these lures is that it supports the recording of our native longhorn beetles as well, which is of interest to Michael Pocock (Biological Records Centre).

It is extremely unlikely that Asian longhorn beetle will be recorded by anyone taking part in the trial. However, if ALB is found during this trial then the recorder has a legal obligation to report it to the Forestry Commission e.g. via TreeAlert. The site would be re-surveyed to see if the species is present there or nearby. If ALB is found to be established, eradication could be attempted, which coudl have a negative impact on the site. It is essential that the landowner understands this and gives consent to the recording.  However, we re-iterate that from our current knowledge it is extremely unlikely that ALB will be found during this trial, although if it was then early detection and eradication is vital to stopping ALB from becoming established in the UK.


This trial is being run by:
It is being funded by Early Detection project of the LWEC Tree Health Initiative.

For further information please email Michael Pocock.


More about longhorn beetle recording

Individual records of identified longhorn beetles can be submitted through iRecord, for passing on to the Cerambycidae recording scheme. However, if the longhorn beetle has not been specifically identitied, we recommend that photos for identification are submitted to iSpot for a community of experts to help with the identification before submitting to iRecord.

Other links about longhorn beetles

For more information see:

About this website

This is the blog of the Conker Tree Science project. Even if you do not take part in the longhorn beetle pheromone trial, you are very welcome to take part in Conker Tree Science and submit records of the horse-chestnut leaf-miner. An app to collect records of the leaf-miner will be launched in the next couple of weeks.

Sunday, 19 October 2014


Today Darren and Michael from the Conker Tree Science project were on Countryfile talking about the project and the leaf-mining moth.

Monday, 5 May 2014

Another May Day - another generation of leaf miners

May Day celebrations in my south Oxfordshire village, with may pole, ice cream van, lots of fun and a flowering horse-chestnut in the background. How typically English!

But once again the signs of change are present. Here are the first of this year's generation of horse-chestnut leaf-miner (Cameraria ohridella). The first mines will be seen in 3-4 weeks - before the trees' leaves turn brown in mid-summer.

This year is the first year we will not be running Conker Tree Science in the way that we have for the past four years. We are presently updating the website ready for the leaf-miner season, with more news soon.

Monday, 31 March 2014

The project in numbers and icons

Here are summaries of Conker Tree Science 2010-13 in numbers and icons. Click on the images to download a larger version or click the link below to get the pdf version with hyperlinks.

Tuesday, 25 March 2014

Press releases

I wanted to gather together all the press releases from the four years of the Conker Tree Science project, so here they are!

22 Jan 2014.The Moth vs the Crowd: Tracking an alien invader of conker trees using people power. [CEH]
30 Aug 2012. Nationwide mission underway to see if blue tits can help save our conker trees [CEH]

6 Jul 2011. Nationwide mission to save conkers from alien invaders gets underway [UoB]
9 Jul 2010. Can wasps help save Britain’s conker trees? [UoB]
10 Jun 2010. Conker trees facing peril from alien invaders [NERC] [UoB]
14 Jul 2009. School pupils help scientists research 'alien' moths damaging conker trees [UoB]