Isolation has led to the appearance of life forms that are unique in the world, as a result of which the Serra de Tramuntana mountain range – an island within an island – stands out for its significant endemic flora and singular plants, essential for the development of diverse plant communities. In fact, the mountain range holds 65 of the 97 endemic species described on the Balearic archipelago, and 65 of the 68 endemic plants in Mallorca. To name one example, nine species of orchids and more than ten species of ferns live in the Serra alone, and nowhere else in the world. The holm-oak grove, that ancient indigenous forest, has its main strongholds here, and the mountains are the only refuge of trees typical of cold climates, like the yew.
Broadly speaking, the vegetation of the Serra de Tramuntana is divided into four plant communities:
- Balearic holm-oak woodland. This is the climatic forest community that would occupy most of the territory if there were no human intervention. In the Serra, the location of this type of woodland has been reduced and contains two sub-groups – the mountain holm-oak woodland and that of the lowlands and coastal areas.
- Wild olive scrub (garrigue). A plant formation typical of warm areas which predominates in lower altitudes. It appears as a consequence of maximum drought conditions that prevent the holm-oak woodland from developing. This garrigue led to the expansion of the agricultural olive tree.
- Calcicole shrubland. The two most representative shrubs of this community are rosemary and heather. It is found in both coastal and mountain areas. The presence of Aleppo pine cover is visible. In the Balearic Islands, pine forests are an entity in their own right and comprise the most extensive tree formation, thanks to their swift growth and opportunism.
- Communities in the highest Balearic vegetation belt. These plant communities develop particularly on terrain where the strength of the wind or the absence of soil prevents the growth of other communities. They are concentrated above all in the highest section of the mountains, near summits and crags. They consist of a very low formation of thorny bushes with rounded forms (cushion-type plants) with a discontinuous incidence and reduced surface cover.
The Botanical Garden of Sóller reproduces the flora typical of the mountains, among others, and a visit is therefore an excellent way of discovering their peculiarities, characteristics and endemic plants.
The trees of the Serra de Tramuntana include specimens that are extraordinary for their size or age, or for their cultural value, and as such they are protected and form part of the Catálogo de Árboles Singulares de les Illes Balears (Catalogue of Singular Trees of the Balearic Islands). Some are several hundred years old, located in extremely beautiful enclaves, like the Pi de sa Pedrissa pine tree (Deià), and Cedre de Massanella the cedar.