Managing the vegetation of an 19 th century park to preserve its picturesque character

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1 Managing the vegetation of an 19 th century park to preserve its picturesque character Paolo Semenzato 1, Sergio Luison 2, Sergio Sgro 3 1. Associate Professor, Dipartimento TESAF, Università di Padova 2. Free Lance Arborist 3. Research assistant, Dipartimento TESAF, Università di Padova

2 Historic gardens and parks are often important elements of the urban forest. These resources, created for the pleasure of their private owners have undergone dramatic changes in their use and management practices, which threaten their survival. Preservation laws and practices are often built around archeological, historical and architectural concepts and are inappropriate for a successful management of trees and vegetation.

3 This is particularly true in landscape style parks in northern Italy. The park style is the Lombardy-Venetia variation of the English Landscape Garden, that became very popular throughout the 19 th century, leading to the transformation of many formal gardens in landscape parks. For their relatively small size, compared to the landscape gardens in England and northern Europe, designers had to employ very detailed solutions to create the picturesque scenography.

4 These park are more difficult to manage than formal gardens. Choices must be made to preserve the scenography of the park through a well planned management of an ever-changing forest structure.

5 At the same time a careful balance between regeneration of the park s forest and the conservation of veteran trees needs to be reached.

6 A detailed GIS model of the park, built from a complete tree inventory, has been produced tress with dbh over 10 cm were inventoried, belonging to 68 woody species (50 broadleaf and 18 conifers). Vegetation survey and analysis: Tree mapping Tree survey Size, Conditions, Health

7 Field survey

8 Complete survey of trees with DBH > 10 cm and large shrubs Depending on size a different level of accuracy was used Survey sheet DBH classes and level of completeness: Ø cm 1 level sheet (red color) Ø cm 2 level sheet (yellow color) Ø > 40 cm 3 level sheet (blue color)

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10 The thematic maps obtained with the GIS were a valuable tool for planning the restoration of the park

11 SURVEY OF THE PARK (1869) THE PARK TODAY (Google Earth, 2012)

12 PROJECT OBJECTIVES Recreating the scenography and the views; Protecting the veteran trees; Rehestablishing the original botanical composition.

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15 IDENTIFICATION OF THE FOUNDER TREES Dimensions For medium and slow growing species, DBH and height are good indicators of age. Historical documentation Cross checking large specimens with historic maps and photographs can further confirm the estmated age. Priority to relevant species Native and exotic species tipically used in 19 century parks were given priority over spontaneous and invasive species.

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19 ACTIONS TO MEET THE OBJECTIVES Deseased and hazard tree felling. Removal of spontaneus and invasive trees for the restoration of original views and scenographies that have been lost. Thinning of woodland areas. Removal of seedlings and saplings in excess. Planting new trees to recreate existing green architecture such as the hornbean and horsechestnut alleys, and to reintroduce some peculiar species. Safeguarding the veteran trees with specific arboricultural tecniques. Preserving the entire tree population and the safety of the visitor with appropriate arboricultural management. Restoration and management of the understory vegetation.

20 TREE FELLING

21 NEW PLANTING

22 SECURING THE FUTURE OF VETERAN TREES Veteran trees were subject to a thourough evaluation of health and mechanical properties. Resistograph

23 Sonic and electric tomography

24 Pulling test

25 The restoration project of Villa Bolasco has been financed with EU funds Operations are schedule to start this coming summer. Another grant has been awarded by the Regione Veneto to the University of Padova to establish in Villa Bolasco a: Center for historic garden and veteran trees protection and restoration This research center will be managed by our Department