Elimination of alien woody species – A great achievement for Action C2!

This is one of the concrete intervention actions aimed at “restoring” and re-naturalizing habitats. In general, these include soil interventions, removal of invasive species, and enhancement of floristic composition. Additionally, the development of guidelines for habitat management and improvement is planned.

The purpose of Action C2 is to reduce the presence and abundance of the following alien woody species: Robinia pseudoacacia, Prunus serotina, Ailanthus altissima and Quercus rubra. These species are listed in the Black Lists of the Piedmont Region (D.G.R. 46-5100 of 2012, D.G.R. n. 1-5738 of 2022) and the Lombardy Region (Annex E of L.R. 10/2008); Ailanthus altissima is also among the invasive alien species of Union concern (EU Regulation 1143/14).

In particular, interventions included felling, uprooting of young individuals, removal of their vegetative parts left in the soil and stump removal. Additionally, in the ZSC Po-Sesia-Tanaro Confluence, as part of Action C4, endotherapy with a plant protection product was also used as a containment method.

Below is a brief summary for each Natura 2000 site:

SAC IT2010013 – Ansa di Castelnovate (Vizzola Ticino) – Habitat 2330
Area of intervention: 5,270 m²

The removal of alien woody species (Robinia pseudoacacia, Prunus serotina and Ailanthus altissima) was carried out in multiple phases:

1. September 2021:
   • cutting (manual and mechanized) and uprooting (manual and mechanical) of tree and shrub specimens,
   • processing, chipping of residues, and removal of waste material (including branches and roots) through stacking, extraction, and disposal at the landfill.
2. 2022 and 2023: successive cuts repeated over two consecutive years to control the regrowth of alien woody species. Mechanized cutting (using a mulching machine) performed during the vegetative season to enhance effectiveness. The mulched material was removed using the mulching machine.
3. July 2023 and July 2024: additional mowing interventions targeting woody regrowth.
   

SAC IT2010013 – Ansa di Castelnovate (Vizzola Ticino) – Habitat 6210
Area of intervention: 13.100 m²

The removal of the alien woody species Robinia pseudoacacia was carried out through interventions executed in multiple phases:

1. September 2021: control of the regrowth of Robinia pseudoacacia through mulching interventions.
2. May, July and October 2022: the same interventions were repeated during the vegetative season. The mulched material was removed using the mulching loader.
3. July 2023 and July 2024: additional mowing and manual cutting interventions targeting the woody regrowth.

SAC IT2050005 – Boschi della Fagiana (Pontevecchio di Magenta) – Habitat 6210
Area of intervention: 13.500 m²

The removal of alien woody species (Robinia pseudoacacia and Prunus serotina) was carried out through interventions executed in multiple phases:

1. December 2021: cutting and uprooting of tree and shrub specimens, including the extraction of stumps, followed by the removal of residual material (branches and roots) using a hydraulic excavator.
2. February 2022: additional mechanized cleaning and manual raking.
3. 2022 and 2023: successive cuts repeated over two consecutive years to control the regrowth of alien woody species, particularly Robinia pseudoacacia. The mulched material was removed using a mulching loader.
4. July 2024: additional mowing intervention targeting the regrowth of alien woody species.

SAC IT2010010 – Brughiera del Vigano (Golasecca) – Habitat 4030
Area of intervention:6.650 m²

The removal of alien woody species focused exclusively on Robinia pseudoacacia and was carried out through interventions executed in multiple phases:

1. September 2021: control of Robinia pseudoacacia regrowth through mulching interventions.
2. July, August and October 2022: the same interventions were repeated during the vegetative season. The mulched material was removed using a mulching loader.
3. July 2023: additional mowing intervention targeting the alien woody regrowth.

SAC IT1120010 – Lame del Sesia e Isolone di Oldenico (Greggio) – Habitat 6210
Area of intervention:7.600 m²

The action was not implemented because the alien woody species were primarily located in the area occupied by the invasive herbaceous species Eragrostis curvula. To avoid the risk of further spreading it through mechanical means, the action was removed from the executive project.

SAC IT1150001 -Valle del Ticino (Pombia) – Habitat 6210 + 2330

Area of intervention: 6.100 m²

The removal of alien woody species (Robinia pseudoacacia, Prunus serotina, Ailanthus altissima) was carried out through interventions executed in several phases:

1. Winter 2021: initial manual cutting using chainsaws or mechanical cutting using excavators for tree and shrub specimens. The resulting wood material was collected and stacked on-site in suitable areas, outside grassland habitats, and left to decompose naturally. A mini-excavator equipped with a forest clamp was used for stacking and, where possible, for stump removal.
2. 2022 and 2023: cutting using brush cutters and/or manual removal of regrowth during the winter season. In 2023, during the vegetative period, regrowth of woody species was cut, accompanied by manual removal of invasive exotic herbaceous species.

SAC IT1120004 – Baraggia di Rovasenda (Lenta) – Habitat 4030
This area was included after the project had been approved.

The intervention concerning Quercus rubra was carried out in multiple phases:

1. December 2020: initial manual cutting using chainsaws for tree and shrub specimens. The resulting wood material was collected and stacked on-site using various standard equipment such as forestry tractors and forest clamps. Subsequently, the material was packaged, transported, and sold.
2. August 2023: second intervention targeting the regrowth of Quercus rubra over an area of 22,100 m². Specifically, manual cutting of shoots using chainsaws was performed, followed by on-site chipping of the residual material and its removal by loading the chips onto trailers.

State of the action: ENDED