Þórsmörk after volcanic ash deposits covered birch woodlands in the Eyjafjallajökull eruption in 2010. The forest survived and healed in few weeks.
The Hekluskógar project area extends over 90 thousand ha, most of which was covered with birch woodlands by the time of the settlement of Iceland. Historical records show that prior to settlement, deposits of volcanic ash and pumice from eruptions in Mt. Hekla were mostly stabilised on the forest floor, preventing secondary distribution. Following the settlement, forest clearance and intensive grazing started. This reduced the resilience of the ecosystem and the following volcanic eruptions initiated large-scale soil erosion. Currently, most of the area is eroded, the soil is poor in nutrients and water holding capacity and frost heaving is extensive. Erosion is extensive, primarily wind erosion, but during spring thaw also water erosion. Therefore, natural establishment of seedlings is limited.
Due to the size of the area, low cost methods are essential. Therefore, the restoration of woodlands will mostly rely on colonization of birch and willows rather that large scale planting. To facilitate this, birch seedlings and willow cuttings will be planted in small groves or woodland islets, from which these species will colonize surrounding areas during the next decades. Efficient natural colonization in the vicinity of old birch forest remnants in the area suggests that this is a feasible method. However, stabilizing the soil in the nearby areas is needed to create favourable conditions for woodland expansion by seed. This is done by spreading inorganic or organic fertilizer onto the land in order to facilitate the establishment of soil crust and local flora. If the soil surface is very unstable due to active sand drift, sowing a mixture of grass species is also needed.
Since the Hekluskógar project started in 2007, all planting, spreading of fertilizers and sowing of grass has been mapped and stored in a GIS database. Several research projects have been conducted in the area, and some are on-going, both looking at ecological factors and growth techniques.
Local landowners in the area have been encouraged to participate in the project, mostly by planting birch seedlings in their land which are provided by the project. Seven years after the Hekluskógar project started, 210 landowners had joined the project and more than 2,3 million seedlings had been planted. In 2014, the afforested area covered more than 1200 ha divided into numerous small patches throughout the area which have already started to facilitate self-seeding.