Scenario 8: Large open space open to the general public
Scenario 8 concerns a collection of urban open spaces including parks, grassland and 170 ha of secondary and ancient woodland where public access is largely unrestricted. Four areas are locked at night. There are a number of ponds, including swimming ponds, areas of amenity sports fields, five cafes and four car parks.
The parks and woods contain many important ancient/veteran trees and landscape trees that were planted during the 19th century. During the year, several large events take place on the site, including cross-country championships, park runs, art fairs, funfairs and a circus.
Three sites totalling 300 ha 
More than 25 000General information
Ownership/control of management
Responsibility: There are three separate sites that are managed by a single responsible ownership body. The Site Manager has overall responsibility for the running of the sites, implementing policy and strategic and operational decisions. Responsibility for the safety of all trees is held by the Arboricultural Manager, and is delegated to the Tree Officer. All tree-related issues are generally managed internally.
Arboricultural competence: The Arboricultural Manager, Tree Officer and Tree Team Leader are qualified in arboriculture and have different levels of experience. Some team members are qualified in veteran tree management and attend relevant conferences and events on arboriculture and ancient and veteran trees. A small in-house team of qualified and experienced arborists assists with various duties.
Access
The main site is divided by busy A and B roads and a railway track runs along the southern-most boundary of the site. All three sites have busy roads and bus stops adjacent to one or more external boundaries. A variety of access tracks criss-cross the site, ranging from tarmacked vehicle tracks to informal desire paths. Other target areas include lockable play and education areas, car parks, sports areas and swimming ponds. The sites host public events throughout the year.
The largest area is open all year round with 24-hour unrestricted access to most of the site. In accordance with the local Extreme Weather Protocol, some park areas are locked during poor weather.
Benefits of trees
The trees and woodlands form a significant part of the open space as an amenity, habitat and education facility. The importance of public access to semi-naturalised open space, including trees and woodlands within an urban environment, is considered to be highly important. The specific retention and proactive management of deadwood on living and dead trees, alongside other conservation works, actively contributes to increased biodiversity on site and an enhanced visitor experience.
Groups of students, tree professionals and members of the public are regularly taken on tours of the site to demonstrate the type of tree management undertaken and to share learning opportunities. To ensure that the tree management on the site is evolving, active international collaboration takes place with professionals from various relevant tree and conservation disciplines.
The site also hosts walks for the public and even international visitors and occasional interns.
Natural living organisms
The tree-management team are aware that trees and woodlands are dynamic adapting organisms. They have experienced some of the cycles of planting, ageing, decline, decay and death that all organisms undergo and the value they provide to people and wildlife in all their life stages.
Long-term management has demonstrated that while all tree failures cannot reasonably be prevented, a balanced and proportional approach to tree risk management can provide an acceptably safe natural environment for the public to derive benefit and enjoy. In recent decades, the management of new pests and diseases, particularly Massaria disease of plane, oak processionary moth and Chalara ash dieback, has become increasingly important.
Strategy
Management
As part of a wider group under local authority control, the local tree policy is informed by the Open Spaces Department policy. The approach to tree management has evolved significantly over recent decades. Previous attitudes to the removal of any dead or dying trees and parts of trees have been replaced by a zoned, risk-based approach that is mindful of habitat retention and creation. When occasionally required, access to specialist decay detection equipment assists in taking an informed approach to risk management. The site has also developed a separate focused programme of veteran tree management.
Occupancy zones have been identified so that that areas are inspected according to the level of usage. High and medium occupancy-zone trees are inspected annually and lower-usage areas are inspected on a two- or three-yearly basis.
A database that is used to record all tree failures shows that there are, on average, 80 failures a year across the land area. This is used by the tree team for discussion to review management decisions.
As well as formal inspections, the team perform many unrecorded informal checks throughout the year, both while performing daily duties and after significant weather events. Rangers and park keepers and, occasionally, public visitors also report failures and obviously defective trees. The tree safety system is audited annually by an independent tree safety consultant
Competence
Survey work is undertaken by in-house qualified and experienced arborists with access to decay-detection equipment when necessary.
Records
The dates of formal checks and inspection are held on the database, scheduled according to occupancy zones. Remedial tree work is prioritised and recorded on the software system. Records of minor works are delegated to a crew work list. The survey software system provides the framework for management of trees according to levels of risk and for maintaining records over time.
Evaluation
The site managers recognise that the threat trees pose to public safety is generally low. In the event of an accident involving one of the trees, the system in place is sufficient to demonstrate ‘the conduct to be expected from a reasonable and prudent landowner’.
The Open Spaces management is committed to following its tree safety policy, but tree safety is only one element of managing trees. Long-term staff site knowledge of the tree stock and the condition of the trees allows a balanced approach to safety and habitat retention.