Brief description of the flora of Canary Islands
The flora of Canary Islands includes 1,750 or 1,800 species of plants; of which 5001 are endemic, another 500 are native to the Macaronesian region and the rest have probably been introduced in modern times, after the conquest of the islands.
The flora of Canary Islands seems to have originated from the European subtropical flora of the end of the Tertiary. Fossil remains of various species, found in the European Mediterranean region and southern Russia, are identical to some endemic species that currently exist in the Canaries and Madeira. These species became extinct on land at the end of the Pliocene period due to the disappearance of subtropical climate, typical of the Tethys Sea coast. The extinction was caused by the glaciation that affected the northern hemisphere and the process of desertification that originated the Sahara desert. However, most of these species (with the exception of tropical elements) could survive on the islands due to their position in the ocean and their considerable height. These factors in fact attenuate the extreme temperatures that caused the extinction of their relatives on the mainland.
The land and the climate of the Canaries favors the creation of “vegetation zones” or habitats that can be grouped according to the common characteristics and species. These areas tend to be distributed at more or less defined altitudes. The altitude of these vegetation zones varies according to the orientation of the slopes (which influences the precipitation), the topography of the islands and the area.
The flora of Canary Islands is divided according to characteristic areas, here is the list of this vegetation areas
Low area or Xerophytic
It is a Mediterranean or Saharan climate zone. The Xerophytic zone extends from the intertidal zone up to a height that can reach 700m, where it meets forest areas. It is characterized by a succulent vegetation, often of euphorbia and cactus or semi-desert shrub vegetation, with brooms and halophytes. Even more this area is threatened by the development
Usually occupies the range between 200 and 600 meters above sea level, has a Mediterranean climate and is the transition zone between the area xerófita and forest proper. Certainly trees such as juniper (Juniperus canariensis), olive (European olea cerasiformis), mastic (Pistacia lentiscus) are common here, either alone or in groups. This area is often highly degraded because it coincides with areas of high population density.
This area usually occupies soils soaked by heavy rains. It is essentially located in favourable areas of the north between 400 and 1500m, where it benefits from the humidity provided by the trade winds, which at these altitudes form a blanket of clouds. Consequently the Wood includes two subtypes: Laurilsilva and Fayal-brezal.
This area is home to species, such as laurel (Laurus azorica), barbusan (Apollonias barbujana), tilo (Ocotea foetens) or the viñátigo (Persea indica). These, together with associated species of the undergrowth constitute the Laurisilva. Laurel is considered a relic of Mediterranean Tertiary or Cenozoic vegetation.
This area is usually between 1200 and 2000 meters, existing in the islands of El Hierro, Gran Canaria, La Palma and Tenerife.
It is dominated by the presence of the Canarian pine (Pinus canariensis) although it co-exists partly with shrubs such as the laburnum (Adenocarpus foliolosus), cistus (Cistus symphytifolius) and thyme varieties (Micromeria spp.). It also houses other species, such as some pine trees, and some endemic species typical of this area.
The pine forest, in the past has undergone great exploitation and has been the subject of numerous and extensive reforestation since the 50s of the twentieth century.
Finally in the highest areas of Tenerife and La Palma, above 1900 meters, there are open shrub communities dominated by legumes and practically without trees, except for some cedar specimens (Juniperus cedrus).
Most relevant this area has many endemic species, such as the tajinaste rojo (Echium wildpretii), the alhelí of the Teide, ( Pterocephalus lasiospermus, Pterocephalus porphyranthus) of the Teide (Spartocysus supranubius), (Genista benahoavensis), (Silene nocteolens), the violet of the Teide (Viola cheiranthifolia) etc.
The high mountain area of Tenerife, in particular, is located in the Teide National Park.