Reintroduction of Silene velutina on the islet of Cornuta, Corsica
27 November 2017
The velvet silene (Silene velutina Loisel.) is an endemic species of Corsica and Sardinia, which disappeared from the islet of Cornuta (Municipality of Zonza, Corsica) in 2001.
Preparatory actions for the reintroduction operation (landscape opening, installation of protective cages) were carried out in October (see related article here). A little later, after the first rains, on 20 and 21 November 2017, the National Botanical Conservatory of Corsica (CBNC), the site manager: the “Conservatoire des Espaces Naturel”s (CEN Corse) and volunteers, including students from the agricultural secondary school of Sartene, returned to the islet to carry out the reintroduction operation.
More than 300 plants (6 and 9 months old), packed in 10 cm or 4 cm pots, were transplanted. All potted plants of height greater than 10 cm were cut back before planting.
From left to right: 9-month old plant packed in 10 cm pots, 6-month old plants packed in 10 cm pots and 6-month old plant of 4 cm pot
6 experimental plots of 6 m2 each (marked St on the map below) were established on the site so as to test the effect of different factors (salt spray and wind, exposure, depth of soil, abundance or not of birds, etc).
Map showing the 6 experimental plots
Each experimental plot was divided into 6 zones of 1 m2 each and each zone was subject to a particular treatment:
- Photo St1-1 - fence (cage)/ aeration of the soil / removing organic matter
- Photo St1-2 - aeration of the soil
- Photo St1-3 - removing organic matter
- Photo St1-4 - no treatment (control plot)
- Photo St1-5 - aeration of the soil / removing organic matter
- Photo St1-6 - fence (cage) / aeration of the soil.
The seedlings were then field-installed and mapped.
6 treatments on experimental plot St1
A monthly follow-up is planned during the first year, then, an annual spring follow-up. The follow-up will consist of:
- recording the number of live stems in each of the test plots
- recording their phenology (rosettes, flowering stems)
- identification and mapping the seedlings.
- taking photographs with an angle of view previously established for each plot.
In addition, the various visits to the islet in autumn made it possible to observe the appearance, after the first rains, of numerous seedlings of Lavatera arborea. It will therefore probably be necessary to eradicate them in the experimental plots to promote the development of the silene.
Direct seeding will also be carried out at the beginning of January.
Transportation of the plants to the islet
Establishment of an experimental plot with 6 treatments (1st 3 photos) and appearance of numerous seedlings of Lavatera arborea after the first autumn rains (last photo)