¶ Xanthoria parietina
¶ Groot dooiermos (Common orange lichen)
Lichens
¶ Why this species, in the context of the Amsterdamse Bos
The bioindicator that reads the Bos's nitrogen problem. Bright orange, abundant on bark and stone everywhere in the Bos. A strong nitrophyte — its dominance signals the high atmospheric NH₃ load from Schiphol, the A9/A10, and Amstelland livestock. The absence of N-sensitive lichens like Usnea, Lobaria pulmonaria, or Pseudevernia would signal recovery; their continued absence here measures the pollution.
¶ Facts from the graph
| Total observations in the Bos | 125 |
| First recorded | 1979-06-09 |
| Last recorded | 2026-05-13 |
| Max rarity tier | 1 — common |
¶ Top sub-locations within the Bos
- Amsterdamse Bos - Bosbaan / Duizendmeterweg — 21 observations
- Amsterdamse Bos - Koenenbos — 18 observations
- Amsterdamse Bos - Polder Meerzicht — 15 observations
- Amsterdamse Bos — 13 observations
- Amsterdamse Bos - Kleine Kinderbad — 11 observations
¶ Explore
- View this species on the Bos map → (all observations, plotted geographically)
- Species page on waarneming.nl
- Bos-filtered observation list on waarneming.nl
- One example observation
Data derived from 136,107 waarneming.nl observations at location 5013 (Amsterdamse Bos), scraped May 2026. Bos-context text: manually composed from the Bosplan 2020–2030, amsterdamsebos.nl, and the existing Het Onzichtbare Zichtbaar dossiers.