This lichen is easy to find and easy to recognise. It is large, green, and covered with a network of ridges. It is found on trees with alkaline bark, such as hazel, willow, ash, sycamore, mature oaks and beech. It also sometimes grows on rocks in shady humid places. It is only attached at the point of origin, and has little contact with the bark or rock as it spreads out or hangs down over it.
Tree Lungwort is only common in the west of Scotland and has disappeared from many other parts of Britain due to pollution. Its abundance in our area is a sign that pollution has been minimal here. Long may this continue. There are still populations in many other parts of the country but they are much more restricted in habitat than they are here, and rarely fertile.
This lichen is on the Scottish Biodiversity List, meaning that it is “of principal importance for biodiversity conservation in Scotland.” Public bodies have a duty to take into account the conservation needs of such species. As part of our agreement with SNH, LNHG is committed to raising awareness of the Scottish Biodiversity List and the species on it, so future Species of the Month will often be from this list.
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As well as having three methods of reproduction (apothecia, isidia and soredia) and containing two photobionts (a green alga and a cyanobacterium), Tree Lungwort is host to a large number of fungi, which are obviously just as vulnerable to pollution or habitat loss as the lichen itself, since they can’t exist without it. One of these, Tremella lobariacearum, forms the pink blobs in Jan’s photo, above right, from our recent North Creagan field trip. Most of the others require specialist skills to identify but you will find all kinds of suspicious discolorations and deformations on L pulmonaria which may be due to one of these fungal epiphytes.
When it dries out, Tree Lungwort turns this pale grey-green colour. This photo also shows some bits of the underside which is whitish, with bulges corresponding to the depressions between the ridges on the topside.
Please send in your sightings using the form below, or email sightings@lnhg.org.uk with the details if you prefer. If you are not sure of the identity of your species, please send a photo to sightings@lnhg.org.uk, or put one on the LNHG Facebook page.
Comments or questions are welcome.
By filling in this form you consent to your record being passed on to the appropriate recording scheme. Your email address will not form part of the record and will not be passed on to anyone.
Carl Farmer
LNHG Biological Records Manager
Note you can still send in records for past species of the month.
All photos and other content copyright © Carl Farmer except where stated.




