Question 1

What environmental benefits do urban forests provide to cities?

Accepted Answer

Urban forests clean air and water, control storm water runoff, prevent erosion, reduce noise, and conserve energy. They also provide wildlife habitats, nesting sites, and travel corridors for animals. Socially, urban forests connect residents to nature, enhance architecture, and offer educational opportunities about the natural world.

Question 2

How is tree condition assessed during an urban forestry survey?

Accepted Answer

Tree condition is evaluated using six visual assessment categories: trunk condition, growth rate, structure, insects and disease presence, crown development, and life expectancy. Each category receives a rating based on unhealthy features. The combined scores produce an overall health score ranging from excellent to very poor.

Question 3

What is diameter at breast height and why is it measured in tree surveys?

Accepted Answer

Diameter at breast height, or DBH, is the tree trunk diameter measured 4.5 feet above ground. This standardized measurement is recorded during urban forestry surveys because it directly correlates with a tree's ability to provide ecosystem services. Larger trees with greater leaf area deliver more environmental benefits.

Question 4

How does GIS software help manage urban forestry data?

Accepted Answer

GIS allows extensive data collection and management by combining geographical and tree-survey data to produce accurate maps of urban forests. Programs like Google Earth and ArcGIS enable spatial analysis of tree characteristics, pattern identification, and quick database updates. This framework supports decision-making for tree removals and supplementary plantings.

Question 5

What information does the National Tree Benefit Calculator provide?

Accepted Answer

The National Tree Benefit Calculator is a free online tool that estimates monetary benefits of urban trees. Users input tree trunk diameter and land-use type to receive economic valuations across key areas including property value, air quality improvement, and storm water control benefits.

Question 6

How do you record tree location data during a field survey?

Accepted Answer

A GPS receiver records geodesic coordinates of latitude and longitude for each tree location. Postal addresses are also noted. Once collected, this location data is entered into GIS software programs for spatial analysis. GPS coordinates should be converted to decimal degrees format before importing into ArcGIS.

Question 7

What data should be collected when surveying trees in urban areas?

Accepted Answer

Urban tree surveys record species, location coordinates, postal address, diameter at breast height, health condition score, land use type, and trunk diameter. Species identification can be assisted by using a tree identification dichotomous key. Data is typically collected by city block, with each tree assigned a number for tracking.

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