Kalanchoe × houghtonii, an invasive hybrid that threatens to colonize the new volcanic stream on La Palma
After the devastating volcanic eruption that put the island of La Palma on the news all over the world, it seems that calm has returned to this little corner of the Atlantic.
The new Cumbre Vieja volcano (2022). Author: Iván Pérez.

A. Rumex lunaria and Kleinia neriifolia on the slope of Teneguía volcano (2017). B. Stereocaulon vesuvianum Pers. lichen in the San Juan volcano volcanic stream (2019). C. Aeonium davidbramwelii fblooming in the badlands of Teneguía volcano (2017).
Author: Iván Pérez.
This succulent plant seems to be designed to conquer dry environments, being increasingly common on the coasts of Mediterranean climate. But to our surprise, we found seedlings of this invasive growing on the sand emitted from the heart of the island in the past months. Also known as “mother of thousands” or “mother of millions”, it grows comfortably between the rock and the newly formed sand and, although it is not yet as frequent in the Canary Islands, it is increasingly easier to find it outside gardens, competing with the local flora.

D. Adults of K. houghtonii growing near the Tajuya viewpoint, El Paso (2022). E. K. houghtonii propagules growing on the sand emitted by the volcano (2022).
Author: Iván Pérez.
In this case, some adult specimens were located less than 20 km from the volcanic cone, coexisting with the Forsskaolea angustifolia Retz. grass, a Canary endemism present in all the islands. This should serve as a warning sign, since in other archipelagos of volcanic origin such as Hawaii, the Kalanchoe genus has managed to invade even the most remote places. The great production of propagules by the leaves, added to their CAM metabolism, makes these plants true fighters for survival, their eradication being certainly complicated since a single individual can produce hundreds of clones.
From the Botanical Institute of Barcelona, we send all our support to La Palma, especially to those that have lost so much to this catastrophic and impressive natural event. Let’s hope that nature will allow a satisfactory economic and ecological recovery as soon as possible, and that the badlands created by the unnamed volcano will not become the home to the harmful invasive flora.