
Removal of flammable material
Javier Incera Goyenechea/Fototeca CENEAM
Workers clearing weeds in the experimental plot in Liendo.
Before starting the monitoring and control of the common fern populations, it was necessary to remove all the specimens of this species present in the two experimental plots where the project fieldwork was carried out, a task that was performed using hand-held brushcutters. In this way, as well as eliminating the potential risk of fire by removing a highly flammable material, it was possible to homogenise the presence of ferns in the plots and to observe, from the beginning, their growth cycle.

Sampling
Javier Incera Goyenechea/Fototeca CENEAM
Operators collecting and transporting fern samples in the experimental plot in Colindres for subsequent laboratory analysis.
In the study of the ferns carried out in this project, different parts of the plant were analysed at different stages of growth, in order to determine, in each of them, the quantity the amount of active ingredient they contain and, consequently, the parts and the time when it is of most interest to collect the active ingredient. and when it is of most interest to harvest the plant. For this purpose, it was necessary to collect different samples separately and treat them with great care to avoid their deterioration until they reached the laboratory.

Laboratory analysis
Javier Incera Goyenechea/Fototeca CENEAM
Rotary evaporator used in the laboratory of the ICA for the removal of solvent in the sample extraction process.
The laboratory study of the samples collected in the field was carried out at the ICA of the CSIC. There, the samples were worked on in three phases: Phase 1 (Sample extraction), Phase 2 (Chemical Analysis and Biological Profile), and Phase 3 (Toxicological Analysis). In the first phase, the organic extraction of the samples was carried out from dried and ground leaves by Soxhlet extraction with ethanol, eliminating the solvent until dryness in the rotary evaporator shown in the image.

Sample extract type
Javier Incera Goyenechea/Fototeca CENEAM
Hermetically sealed bag suitably labelled for shipment to the ICA, where it will be analysed.
Eight samples were collected in the experimental plots and sent to IBBTEC, between April and May 2018, corresponding to two different harvesting periods (autumn 2017 and spring 2018), and at two different developmental stages: early and late. In addition, a manual isolate of the plant's fronds was sent for study. The samples, after being weighed, identified and labelled at IBBTEC, were sent to the ICA of the CSIC for evaluation and study, packaged as shown in the image.

Press conference presentation of the project
Javier Incera Goyenechea/Fototeca CENEAM
Moment of the press conference held to publicise the start of the project and its objectives.
During the execution of the project, two press conferences were held, one for the presentation and the other for the progress of the results, in the press room of the Government of Cantabria with the participation of the Regional Minister of Universities and Research, Environment and Social Policy and Vice-president of the Government of Cantabria, as well as the heads of the other entities involved in the project: Director of the Environmental Research Centre (CIMA), President of the Association of Sustainable Municipalities of Cantabria (MMS), mayors of the municipalities owning the land where the field work was carried out (Colindres and Liendo) and president of the Cultural Association Forests of Cantabria.
The objective of the Pteridum project was to analyze the economic viability of controlling common fern populations (Pteridium aquilinum) in a circular economy system adapted to climate change in the Cantabrian Mountains, and reducing forest fires caused or favored by their presence by controlling their expansion in an environmentally respectful way. In addition, some active ingredients have been obtained from the plant’s residue as a result of the elimination of the fern, such as ecdysone and its ecdysteroid counterparts, and studies have been conducted on the economic profitability of its commercialization for use as a biologically insecticide that is both economically profitable and ecologically proven.