# hard shield fern

*Polystichum aculeatum*

Each leaflet features a small lobe at its base that resembles a tiny, upward-pointing thumb.

- **Taxonomy:** Plantae › Tracheophyta › Polypodiopsida › Polypodiales › Dryopteridaceae › Polystichum
- **IUCN Red List status:** Least Concern
- **Population trend:** stable
- **Biome:** forest
- **Habitat:** Shaded deciduous woodlands, steep rocky ravines, and limestone slopes.
- **Diet:** Autotrophic (photosynthesis, absorbing water and minerals from base-rich soils).
- **Range:** Europe, Western Asia, North Africa
- **Size:** Fronds 30-90 cm long, forming crowns up to 1 meter wide.
- **Lifespan:** 30-50 years
- **Active:** diurnal
- **Threats:** Deforestation, canopy clearance causing excessive sunlight, and ground disturbance from logging.
- **Safe to approach?:** Entirely harmless and safe to approach. You can gently touch its leathery, evergreen fronds. Avoid uprooting or damaging wild specimens. No protective gear or medical actions are necessary.

## About

Polystichum aculeatum , the hard shield-fern , is an evergreen fern native to Europe. It is most abundant in upland regions of the British Isles and western France, where it benefits from the combination of mild winters and moist summers, but also occurs more locally across most of Europe except northern Scandinavia, northern Russia; in the Mediterranean region it is confined to high altitudes. It grows on steep slopes in woodlands. it is sometimes considered an indicator of

## Sources

- Plate: https://gaia-dex.com/species/c5222f5d-5706-494c-8c69-c35567eefb8a
- iNaturalist: https://www.inaturalist.org/taxa/275961
- Wikipedia: https://en.wikipedia.org/wiki/Polystichum aculeatum
- Conservation status: IUCN Red List category, as recorded by Gaia-Dex
- Photo: https://inaturalist-open-data.s3.amazonaws.com/photos/111492449/medium.jpg (Erwin Gruber, CC-BY-SA, via iNaturalist)

Habitat, diet, size and similar notes are AI-written summaries; check them against the linked sources before relying on them.