Summer arrives and the ski resorts close, but that doesn’t mean they will be abandoned until the snow returns. In fact, it is the ideal time to regenerate the mountain after months of the bustle of skiers and machinery with a shock treatment to fix the soil with hoses of water, seeds and plant fiber, a recipe with which the Aragonese Pyrenees reinvents itself every summer to be ready when the cold returns.
A la rica hydroseed. Hydroseeding is a technique for restoring slopes and degraded surfaces that uses seeds, plant fiber, water and fertilizer and is applied under pressure to maximize adhesion and promote germination in steep places.
In the Aragonese Pyrenees, stations such as Formigal-Panticosa, these works are carried out between the months of May and June and then in September, months of good weather where periods of high humidity are concentrated. As Juanjo Pes, director of the station, explains: “By the time winter arrives, the seeds have already germinated. If it is delayed too long and the cold begins, they can freeze inside the ground.”
Why is it important. Because in addition to being beautiful, the vegetation cover is essential: it stabilizes the soil, reduces erosion caused by melting ice and torrential rains and also favors the recovery of use as a ski resort (where compactors frequently pass by). There are studies that confirm that revegetation through hydroseeding manages to control erosion and ensure that native species take hold in the soil compared to those lands where it is not applied.
Context. In the standard hydroseeding method, generic commercial seed mixtures used to be used, but now it has been imposed to use native seeds and it has its reason: a study in the French Pyrenees points out that traditional seeds, although they help stop erosion, are not always adapted to the harsh conditions of the high mountains. Hence Formigal works with a botanical conservatory to obtain local seeds.
In detail. The mixture formula for this type of hydroseeding includes a binder that works as a kind of glue that retains the seeds even on steep slopes. Historically, commercial species are the most convenient, because they are cheaper and grow quickly, but in complicated scenarios such as in the Pyrenees, native species are more interesting because they can withstand that climate better. Once planted, the vegetation takes about two years to develop.
Yes, but. Hydroseeding is a consolidated and convenient technique, but its results are neither immediate nor uniform. In fact, a study conducted in northern Europe found that the positive effect of hydroseeding on canopy formation was relatively small and short-lived, with no significant differences in species richness between hydroseeding and conventional seeding, suggesting that it is highly dependent on local soil and climate conditions.
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Cover | Maria Cassagne and José Noguera
