He Senecio is an herbaceous plant, slightly woody at the base, up to 1 meter high, which comes from a deep root. The stems are upright, usually bald (Sometimes hardly any hairircase), striped, often very branched from the base. The stems have few leaves and these are linear or sub-linear and have 10 to 15 yellow flowers. It has a very small and spring fruit, which is easily spread through the wind.
It prolifers open space in all types of open space, it does not support the competition of bush vegetation. Colonizes dry meadows, gutters, river ducts and areas changed by forest works. And in Mediterranean areas it is usually limited by the availability of water.
Loose Senecios are abundantly present in northeastern Catalonia and adjacent Pyrenean zones. It is also present in points of the Basque Country, Asturia and Castilla Y León. The current problem stems from his presence in different parts of the city of Barcelona.
Catalonia ‘suffers’ from this invasive plant
Loose Senecios They are plants of the genre Senecio And from the same family as the Margaritas (Asteraceae), which are widespread by the Iberian peninsula. Many of them are native, but some are species that have recently been introduced by people and that have become invasive species.
This is the case of Senecio Inaequidens“ known for his expansion in the Pyrenees of the Pyrenees and because it is toxic by cattle, but it is also the case of the Senecio Pterophoruswho recently spread in many natural spaces of the coast and the prelitorral.
‘In the Delta of Llobregat we find an explosion of Senecio Pterophorus bloomBut it is not the only place where we can find it. Since the early 90s, it has been spreading through the canals and alluvial plains of the Llobregat River and the Besòs River until it reaches various natural spaces, such as Montseny or Montnegre-Corredor, ”explains Joan Pino, director of creaf and coordinator of the initiative of the initiative of the initiative of the initiative of the initiative of the initiative of the initiative of the initiative.
The Senecios de Barcelona
Although most media of the Senecios those Catalonia have invaded, is the Senecio InaequidensEspecially because of the problem with the High Mountain Peasantry, There are also two types of Senecio with an impact on the metropolitan region of Barcelona today.
They are the Senecio Ptherophorus and the Senecio Angular. Both flourish in the spring and are of South African descent. “Senecio access to the Iberian Peninsula is caused by human activityThat it probably introduced in the form of hidden seeds in the wool of Africa and transferred to the rivers with washing this material, “says Pino.
Senecio Pterophorus It is one Arbust species Who was first established in Catalonia in the early 80s and has since experienced a major extension in areas of the coast and the prelitor and then extended to many adjacent mountain ranges. At the moment this senecio It has already been strongly discussed in protected spaces such as Collserola, Montnegre-Corredor or Montseny.
Another species that we find in the metropolitan area is the Senecio AngularFrom climbing lower and fleshy leaves that seem to prefer warm climates. That is why it mainly grows along the coast and the coast, which is already a problem in spaces such as such as Montjuïc, the aspect south of Collserola or the coasts of Garraf.
“The most important problems of In penetrating Senecios is that They can compete with indigenous flora, especially for certain sources such as pollinators, because they have a fairly long flowering period and are very resistant species“The ecologist points out.
Postal species for cattle
He Senecio Inaequidens It is also originally from South Africa and therefore is Moderate climates We have in the Mediterranean Sea. In particular, it has been expanded with some preference for the middle mountain areas and, to a lesser extent, in the lowlandEspecially on the edges of some rivers.
Now, in recent years, given the increasingly softer temperatures in the winter, it is much extensive in the mountain areas and has caused consequences for cattle, because it is toxic to the herd. Moreover, it influences the ecosystem and the preservation of Pyrenean Grass Meadows can be affected, which is a real refuge for biodiversity. Currently el Senecio Inaequidens It is in abundance in northeastern Catalonia and is isolated in some areas of the Basque Country, Asturia and the east of Castilla Y León.
This plant has also reached Some of the pilot rooms of the European Project Life Pyrenees4Clima, an initiative to adjust the Pyrenees region in climate changeCoordinated by the Pyrenean Observatory of Climate Change (OPCC) of the Pyrenees Work Community (CTP) and Co -Fastinanced by the European Union, in which Creaf participates as a partner.
One of These affected pilot spaces are located in the Albera Natural Park, an area where the Mediterranean oak with open spaces dominates where cows and goats graze. It also affects another pilot room in La Cerdaña.
“At the moment, From the project we evaluate, together with the UAB veterinary faculty, if the Senecio is a risk for the pilot roomEither because of the ability to impoverish the feeding value of natural meadows or for possible effects on cattle. Moreover, we also want to identify what management of forest, animal husbandry and meadows is more effective in controlling the expansion, ”explains Diana Pascual, a creea -researcher and project member.
Checking the expansion of the Senecios
What do we do for this reach Senecios What is expanding in the field of territory? According to Pino, “We can try to control it in some particularly valuable areas, where there are habitats important or in protected spaces, but we can do nothing but this”.
The reason is that, As soon as a species has been set in an ecosystem and is in the entire phase of colonization, it is very difficult and expensive to eradicate it. Moreover, the Senecio Inaequidens It has a large dispersion capacity in both room -the seeds spread very well with the wind -and in time -the seeds tolerate long periods in a latency phase until they have the opportunity to germinate.
The only way to eliminate them is to start them directlyBecause they are resistant to herbicides that, on the other hand, are not recommended option in habitats such as grass meadows such as Mountain. By means of That the efforts must be made in the phases of prevention and supervision of the arrival of invasive plants.
In that sense, we have led from creea to the development of two lists –The blacklist (more urgent) and the Red List – with the most dangerous species that Catalonia can enter and where you must work priority. We have done it within the framework of the Exocat project, which has been studying the series of exotic species of Catalonia for more than 10 years and in particular those who are becoming intruders.