horns out on the damp tree trunks
- Size
- Width: 2–5 cm
- Lifespan
- 1–3 years
- Diet
- Photosynthetic epiphyte. Obtains moisture and nutrients from air and rain. Requires high humidity, stable bark surfaces, and protection from direct sunlight.
- Habitat
- Grows on bark of trees, rotting logs, and damp rocks in humid, shaded forests. A creature of the tree trunk where air is damp. Forms small, dark green, leafy mats with distinctive horn-like sporophytes.
- Range
- Found throughout North and South Islands on bark of native trees, rotting logs, and damp rocks. Most common in lowland and montane forests with high rainfall. Also found in tropical and temperate regions worldwide.
- Endemism
- Native
- Main Threats
- None significant. Common and widespread in humid, shaded forests. Localised threats include forest clearance, removal of old trees, and climate change reducing humidity.
- Population
- Not Threatened. Common on bark of native trees, rotting logs, and damp rocks in humid, shaded forests throughout New Zealand. Widespread in tropical and temperate regions.
- Conservation Status
- Not Threatened
- Human Risk
- harmless
- Handling Note
- common hornwort, safe to handle
- Conservation Note
- Native hornwort; not assessed by NZTCS as bryophytes are generally outside the scope of current threat classifications.
- Te Ao Māori
- No recorded Māori name distinguishes dendroceros hornwort from other hornworts. Hornworts were generally called pūkohu or grouped with other small, damp-loving plants. The small, dark green mats on tree bark would have been noticed. They looked like the fur of a creature. No distinct name survives. It was not used as medicine or dye. It was too small and too hidden. Simply part of the forest.
Dendroceros granulatus lives on trees because it could. Its body is a small, dark green thallus forming loose, creeping mats on bark. The thallus is narrow and branching with a distinct midrib and ruffled margin. Tiny granular bumps cover the surface. They give it a rough, textured appearance. Thin, dark green to brownish horn-like sporophytes rise from the thallus. They look like tiny spikes or antennae. It is the hornwort of the arboreal life.
What makes it special is the epiphytism. Most hornworts live on damp soil. Dendroceros has taken to the bark. It gets its moisture and nutrients from the air and rain. It looked at the soil and said no thank you. It decided to live above the ground.
The thallus is olive green to brownish-green. It often blends in with the bark. Under a hand lens, the granules are visible. They are tiny bumps that give the thallus its rough texture. The margins are wavy. The midrib runs down the centre.
Biologically, it reproduces by spores released from the horn-like sporophytes. These grow from the thallus like tiny horns. When they mature, they split open. Thousands of spores release into the damp forest air.
To find dendroceros hornwort is to find the small, dark green mats on tree bark. They are leafy, bumpy, and horned. A quiet rebel on the trunk. It is the hornwort of the tree life. The one that left the ground behind because soil was apparently too mainstream. The one that proves there is always another way to live. No one told it otherwise.