Last sunday in November the Canary Islands celebrated the Day of the Tree. The director of our botanical garden, Stephan Scholz, wants to present us some native tree species of Fuerteventura, most of which are very rare and difficult to find. Let yourself be surprised about what he has to tell us about these rare species.
“On this important day, in this section we don’t want to speak about the great importance of trees for the ecosystems, nor about their importance for cleaning the air and provide oxigen, not to mention things like timber, fruits and other products obtained from them. This is well known and accepted. Also, we don’t want to speak about the numerous introduced tree species from all around the world which are planted in gardens and fields in Fuerteventura and which surely number well over 150 different species.
In this occasion, we want to tell you something about native trees of Fuerteventura. Even if we include large shrubs, there are only a handful of species which occur naturally on the island. Apart from a few exceptions, they are all extremely rare, to the extent that of some species there are fewer than 5 individuals left in the wild! However, none of these tree species are found exclusively on Fuerteventura, but fortunately grow also on other islands of our archipelago or even outside it.
Both the Administration (Townships and Cabildo de Fuerteventura) and the Botanical Garden of Fuerteventura Oasis Park are trying to avoid the extintion of these trees. This is an interesting and beautiful, yet long-lasting and difficult task. It is tedious and sometimes also dangerous to reach the last individuals growing on some inaccesible cliff; often, they don’t have seeds, the vegetative reproduction from truncheons or cuttings may be difficult … but something has already been reached and most of these rare species are cultivated in the native plants section of the Botanical Garden of Fuerteventura Oasis Park.
Today we want to show you three of those species. In the next weeks, others will follow, till we reach the total of about one dozen different trees:
Canary tamarisk (Tamarix canariensis)
The countrymen of Fuerteventura don’t like tamarisks because they salinize the soil. They cannot be tolerated in the neighbourhood of planted fields. In fact, tamarisks like to grow where saline groundwater is available.The salt which the trees take in with the water absorbed by their roots is excreted by the leaves (picture 1). Early in the morning, small drops of very salty water hang on the branches, which later fall down and deposit the salt on the uppermost part of the soil.
But we have to see also the positive side of the tamarisks. Their wood is hard and durable and many things can be made from it. Formerly, it was employed for handles of tools like spades and hoes, also for plows, yokes and window lintels. When a straight stem was found (which didn’t occur frequently), it could be used as a master beam in rural houses and barns. Moreover, the small tamarisk forests of Fuerteventura are te preferred habitat for several bird species like the Sardinian warbler and the turtle dove, apart from many insect species that live on tamarisks.
The Canary tamarisk is not only found on the Canaries, but also occurs in the western Mediterranean region. It has been introduced in many countries, for example the USA, where it is now an invasive species in the marshes and wetlands around the Gulf of Mexico. It is one of the few indigenous tree species of Fuerteventura which is not in danger of extinction, but its populations rather increased in the last 50 years and the species has even colonized some new terrains like the surroundings of the Presa de la Peñita dam not far from Vega de Río Palmas.
Bove’s tamarisk (Tamarix boveana)
Some years ago, a single individual of this westmediterranean tamarix species was found in Fuerteventura. Could it be planted? We don’t think so, because it grows far from human settlements. Tamarisks (picture 2) have very small seeds with hairs that can easily be transported far away by the wind. Could a seed of Bove’s tamarisk have reached Fuerteventura coming from Morocco, where the species also occurs? Are there perhaps more individuals of this species in some lonely place of our island?
Until now, we cannot answer to these questions, but we can show you the differences between the Canary tamarisk and Bove’s tamarisk. The branches and the very small, scale-like leaves are quite similar in both species, but the inflorescences are not. The inflorescences of the Canary tamarisk appear on the tips of young growth and are relatively thin and branched; those of Bove’s tamarisk grow from older branches and are thicker an unbranched. They remind the hanging inflorescences of some willow species. Moreover, the flowers of the Canarian species have five white or pink petals, while those of Bove’s tamarisk have only four pale pink petals.
Canary date palm (Phoenix canariensis)
This elegant palm tree (picture 3) originally only ocurred on the Canary Islands, but it has been planted since a long time ago in all Mediterranean countries as well as in California, Florida, South Africa, Australia and many other places, being a sort of plant ambassador of the Canary Islands all over the world. Of course it is also grown frequently in parks, gardens and along streets in the Canaries, but in the last years many individuals became lost due to a dangerous fungal disease. Planted palms irrigated with cleared waste water are especially prone to this infection, but wild individuals are much more rarely affected.
The fruits of the Canarian date palm are small; compared with the big, sweet dates of the true date palm of North Africa and the Middle East they are hardly suited for any more than as fodder for pigs and goats. However, the Canary date palm has many other valuable properties. Especially on the island of Gomera, people take advantage of them: the stem was used as a master beam in rural houses; hollowed, it served as a bee-hide. From the fibrous leaves hats, baskets, mats, saucers and many other things can be made. However, the most important product is palm honey. It is obtained by cooking the sap of the palm, which flows from the uppermost part of the stem after a great part of the leaves have been removed. In Gomera, this sap is called “guarapo”. Today it is possible to buy palm honey in almost every supermarket, even on the other Canary Islands. It is very good suited for sweetening deserts. The tapped palms don’t die, but the flow of the sap, which is mantained by peridically cutting a new thin layer of tissue on the top of the palm, has to be stopped after some months. So, the palm can recover and emits new leaves. It is then allowed to grow for many years, after which it can again be used to obtain guarapo.”
Did you find all this interesting? If so, then do not miss the next issue of this section, where again we will give you information about native tree species of our island, for example the balo, the wild Canary olive tree, the Atlantic pistacho or the maytenus of the Eastern Canary Islands.
The botanist’s staff of the botanical garden of Oasis Park Fuerteventura wants to remind you that the protection of trees is a task that attains all of us. It is possible to buy some of the species we present in commercial nurseries or even get them without costs on the Day of the Tree in the nurseries of the Cabildo Insular de Fuerteventura located in Betancuria and La Oliva. You may plant some of these species if you are the owner of a garden in Fuerteventura.