Morchella species (Morels)

Dick Peebles has kindly contributed these three profiles, but also read a personal account of his explorations for Morels.

According to the Fungal Records Database of the British Isles there are eight species of true Morels to be found in our islands, with a further three sub-varieties. Of these, only three species and one variety have been found in Scotland.

Morchella esculenta

With 680 records on the FRDBI this is the most frequently encountered species in Scotland and the rest of the British Isles. It is also the largest species, and its ascocarps can exceptionally attain a height of 25 cm. The apothecium (“cap”) is more or less rounded, varying in colour from cream to yellowish-brown and consisting of a honeycomb-like network of irregular pits. At its base it merges abruptly into a white, coarsely-granular stem.

Morchella vulgaris

Other names: M.deliciosa (according to FRDBI)

Less common than M. esculenta with 112 records on the FRDBI this species is regarded by many authorities as merely a variety of the latter. Microscopically the 2 species are very similar with the sizes of both the asci and the spores therein occupying the same range, but some authors maintain there are differences in spore shape and the degree of swelling towards the tips of the paraphyses. The main differences appear to be macroscopic, with the apothecium of M. vulgaris usually more conical and less rounded than M. esculenta, and the colour tending towards greyish-brown rather than yellowish-brown. The apothecium is often described as tapering towards a ridged junction with the stem, and the stem itself is described as finely-granular. Most of these differences are highly subjective, and given the considerable morphological variation within each species I find separation difficult.

Morchella elata

Recorded 149 times on the FRDBI this is the species most likely to be encountered ad hoc in coniferous woodland. There is no doubt that it is seriously under-recorded in Scotland. Generally smaller and darker and more elongated than the 2 species above it also has an apothecium that features rows of pits separated by near-parallel longitudinal ribs which helps distinguish it. Identification can be confirmed by spore size: with a maximum axial length of 25 µm the spores of M. elata are larger than those of the preceding species, which don't normally exceed 19 µm. The variety M. elata var. purpurascens is one of the most important fungi ever detected in Scotland. Found by Carleton Rea on 15th April 1915 at Arrochar it has never been found anywhere else in the world, so if you should find a pointed Morel with parallel ribs and a violaceous hue we would certainly love to hear about it!

It is also worth noting that there is some uncertainty about the M.elata species concept and how this relates to the similar Morchella species. Some would describe the specimen in the right hand photo as M.conica, although others consider M.conica to be the same as M.vulgaris (!). To confuse things further, molecular studies show no difference between M.elata, M.conica and M.esculenta (Wipf et al., 1999). It's a bit of a muddle so the best one can do is record as many details as possible and say who's species concept you have used.

Footnote:

While Morels make delicious eating there are a few caveats:

1. Make sure you really do have Morels and not False Morels (Gyromitra spp.). Consumption of the latter could prove fatal.

2. Always cook your Morels thoroughly – they are toxic when raw.

3. Eat only a small quantity to begin with in case you are allergic to them.

4. Only eat fungi that are in prime condition. Bon appetit!

You'll find some gourmet morel recipes here.

Please remember to submit your records to yourlocal recording group or via the Scottish Fungi online recording form.

Dick Peebles, April 2013

With thanks also to Malcolm Storey and Dave Genney for photographs.

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Morchella esculenta. © Malcolm Storey, 2010, www.bioimages.org.uk.

Morchella vulgaris. © Malcolm Storey, 2013, www.bioimages.org.uk (as M.conica)

Morchella elata/conica growing in shell sand on the Invernaver Site of Special Scientific Interest, Sutherland. © David Genney, 2006.

Maps from the National Biodiversity Network Gateway:

Morchella esculenta

Reference:

Wipf, D; Fribourg, A; Munch, JC; et al.(1999) CANADIAN JOURNAL OF MICROBIOLOGY

Volume: 45 Issue: 9 Pages: 769-778

Morchella vulgaris

Morchella elata

The National Biodiversity Network Gateway records from FRDBI andHBRG datasets are shown on the above maps (see terms and conditions at http://data.nbn.org.uk). Data providers and the NBN Trust bear no responsibility for any further analysis or interpretation of the information in the map.