hints red on the sunny tree bark
- Size
- Width: 2–10 cm
- Lifespan
- 10–50 years
- Diet
- Symbiotic partnership. Fungus provides structure. Alga provides food via photosynthesis. Requires clean air, stable surfaces, and good light.
- Habitat
- Grows on bark of trees, rocks, and wood in open, sunny locations. Forms pale grey to whitish crust with occasional red hints.
- Range
- Found throughout North and South Islands on bark of native and introduced trees. Most common on rough bark in urban and rural areas. Also found in temperate and tropical regions.
- Endemism
- Native
- Main Threats
- None significant. Common and widespread in open, sunny locations. Localised threats include removal of old trees, air pollution, and bark disturbance.
- Population
- Not Threatened. Common and widespread in New Zealand. Particularly on bark of native and introduced trees in open, sunny locations. Also grows on rocks.
- Conservation Status
- Not Threatened
- Human Risk
- harmless
- Handling Note
- crustose lichen, safe to handle
- Conservation Note
- Native lichen; not assessed by NZTCS as lichens are generally outside the scope of current threat classifications.
- Te Ao Māori
- No recorded Māori name distinguishes haematomma lichen from other lichens. Lichens were generally called pūkohu or pukorokoro. Pale crust with hints of red would have been noticed. Looked like colour of sunset. Like blush of leaf. No distinct name survives. Sometimes used as dye. Reddish pigment extracted to colour fibres. Producing shades of pink and red.
It is not always visible. Haematomma ochroleucum looks like it is blushing. Its body is a thin, crusty layer growing on surface of bark or rock. Forming pale greyish-white to off-white patch. Crust is smooth and even. Like coat of pale paint. But look closely. You may see hints of red. Pinkish or reddish-orange tint seeming to glow from within. It is lichen of hidden colour. Looks like something trying to show through. Makes you lean in closer.
What makes it special is hint of red. Haematomma lichen is one of few lichens in New Zealand with reddish tint. Colour comes from pigment sometimes present in fruiting bodies or crust itself. Red is not always visible. Appears only in certain light. At certain times of year. On certain specimens. It is lichen of shy blush. Reveals colour only when ready. Keeps you guessing.
It is a crustose lichen. Meaning it grows flat on bark or rock. Like crust of paint. Rather than upright or leafy. Body is smooth, continuous crust. Often forming circular patches or irregular stains. Fruiting bodies or apothecia are pale pinkish to reddish-orange. Often with raised, paler rim. Under hand lens, apothecia are beautiful. Tiny discs with powdery surface.
Biologically, it is a partnership. Fungus and alga living together. Fungus provides structure and protection. Alga provides food through photosynthesis. Apothecia are spore-producing structures. Releasing spores into air.
To find haematomma lichen is to find pale patch with hint of red. Pale, crusty, and blushing. Living secret on bark. Have to look closely. Have to catch it in right light. Have to be patient. It is lichen of hidden colour. Looks like something trying to show through. Proves most beautiful things are often most subtle. It carries on regardless.