Cetraria ericetorum and Flavocetraria cucullata

Today’s entry was written by BPotD work-study student, Katherine. She writes:

For today’s entry we have two lichens, Cetraria ericetorum and Flavocetraria cucullata. Many thanks to Richard Droker (aka wanderflechten@Flickr) (Daniel adds: I believe the vascular plant in the image is Sedum stenopetalum).

Cetraria lichens are commonly known as Iceland lichens, Icelandmoss, or heath lichens. While Cetraria ericetorum is commonly known as Iceland lichen, Centraria islandica (as inferred by the name) is known as “true Iceland lichen”, according to Brodo et. al.’s 2001 tome, Lichens of North America (hereafter referred to as Brodo, as he was the principal author). The USDA lists two subspecies of Cetraria ericetorum, Cetraria ericetorum subsp. ericetorum (cetraria lichen) and Cetraria ericetorum subsp. reticulata (reticulate cetraria lichen).

In Lichens of North America, Cetraria ericetorum is described as having a pale to dark brown usually-curled thallus (body) with narrow lobes 1-3mm across, which may become fused where the edges touch. However, according to the Lichen Flora of the Greater Sonoran Desert Region Vol. 1, it may be anywhere between 0.5mm and 8.0mm in breadth. Brodo goes on to describe Cetraria ericetorum as growing on the ground with grasses and heath, and, in order “to tell one species of Iceland lichen from another, look for the white pseudocyphellae [= “a tiny white dot or pore caused by a break in the cortex and the extension of medullary hyphae to the surface”] on the branches”.” Furthermore, that “the lobes of [Cetraria ericetorum] are narrower [than Cetraria islandica], and [Cetraria ericetorum] never contains fumarprotocetraric acid”.

The Consortium of North American Lichen Herbaria (linked above re: Sonoran flora) cites that Cetraria ericetorum is found on “soil and moss, or rarely on bark or wood” in “temperate [or] boreal areas of western North America from low altitudes to alpine areas and at high altitudes” (distribution map). Brodo shows a range further northwards into most Canadian provinces, with some gaps in northern Alberta and central Saskatchewan.

The second species present belongs to the genus Flavocetraria. Brodo characterizes them as small to medium-size, with pale greenish yellow to yellow colouring, having a smooth lower surface which is the same colour as the upper surface, without any rhizines or cilia and having white medulla [“internal layer of the thallus or lecanorine apothecium, generally composed of loosely packed fungal hyphae”]. He also notes their resemblance to the genus Cetraria, except for their colour, and note that “several species of Cetraria grow in the same habitat” as evidenced by this photo of the two growing together.

Flavocetraria cucullata may be “2-6 (-8) mm wide and 25-60(-80) mm high, ruffled at the margins, and curled inward, almost forming a tube (sometime fusing where the edges touch), often curving back at the tips […] the base of thallus [may often become] red-violet”. The species is found “on the ground among mosses and heath” and “in open conifer woodlands and tundra, usually at high elevations”. Brodo also reports that Alaskan indigenous peoples incorporated this lichen as a flavouring for fish or duck soups.

The distribution map for Flavocetraria cullata is available via from the Consortium of North American Lichen Herbaria.

DigitalMycology.com provides several photographs which may help for distinguishing between Flavocetraria cucullata and Flavocetraria nivalis, a very similar looking lichen: Flavocetraria.

Cetraria ericetorum and Flavocetraria cucullata

7 responses to “Cetraria ericetorum and Flavocetraria cucullata”

  1. Mary Wilson

    Can one eat lichens? Any recipes?

  2. Connie Hoge

    Sure is pretty.

  3. Sally

    Thanks for this one! I always love it when you do lichens… and these are some of my favorites. I think I see a strand or two of the very white Thamnolia vermicularis in that mix too, and there may be a dark pruinose lobate thallus on the upper left as well. (At least that’s what I would call it; my terminology may be rusty.)
    Mary, some lichens are edible, but others are quite poisonous. And, from what I hear (not having tried them), edibility doesn’t imply palatability. Some are “famine foods,” eaten only in times of desperation, as I understand it.

  4. Mary Beth Borchardt

    Katherine,
    Thank you for your beautiful lichen entry! I am a new contributor to the large pool of photos in Flickr and I have just now recognized Ursus Californicus as the orange lichen in one of my photos in my set Yellowstone and Grand Teton Range. I am just a nature and plant lover, and have no ability to categorize or identify any of the plants, etc. in my set. If you would like to do so on any of my photos, I would appreciate it very much. Also, any other member’s input/identification/posting of my photo with identification, etc. would make me very happy.
    I so enjoy looking at each daily entry and ID.
    Thanks so much to you and everyone on this site!!

  5. natalie barringer

    Thanks so much for your interesting photo and explanation here. I always like the little tidbits such as the use of this as food,etc. I really look forward to each botany entry,it never fails to help me learn or appreciate what nature offers and we sometimes miss.

  6. Katherine

    Hello, thank you everyone. For Mary, as mentioned F. cucullata is edible, I’m not sure about C. ericetorum. As Sally mentioned, they’re not usually that tasty according to the references I’ve seen. Regarding identification, I leave that to Daniel and colleagues at the gardens, unfortunately, it is not my speciality. Identification of lichens however, may often require chemical reactions be done and may not be possible to completely identify by photographs. Certainly I enjoy looking for information regarding edibility/medicinal/ or remedial properties, so I’m happy you appreciate the effort there. 🙂

  7. phillip

    ..could be a painting of Van Gogh..

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