City Trees

For these communities, advanced technology approaches to urban forest management, including light detection and ranging (LiDAR) and using big data, are constrained by limited budgets. The cutting-edge inventory techniques popularized in conference presentations and publications in peer-reviewed journals are out of reach for the budgets of small, rural municipalities. While this is also true for some cities, many of the rural communities are facing a large, unencumbered forest with tens, if not hundreds, of trees per indi- vidual property (Figure 1). In a recent research project on wildfire preparedness and political ecology, we (see acknowledgements) found that properties with a smaller lot size than most cities had an average of approximately 125 trees per property. Few property owners were readily managing these forest stands, instead leaving the stands to follow natural processes unless posing a risk to property infrastructure. These challenges are a legitimate and pressing concern for assessing what we have—the first component of the simplified four-step planning cycle. If we don't measure the urban forest, we cannot develop a management plan and portfolio specifically for the spatial and temporal contexts of that forest. In areas on the cusp of large-scale losses to invasive forest pests, such as emerald ash borer (Agrilus planipennis) or Dutch elm disease (Ophiostoma spp.), without forest assessment, it is difficult to forecast the potential losses (and thus financial consequences) of pest population influxes. Recognizing Management Objectives Communities frequently use the i-Tree suite of software to measure and model the current state of urban forests. The ecological modeling which underscores its functionality is largely based on forest stands and corrected for urban growth pat- terns, despite the differing biometrics of urban trees. In rural communities, distance-dependent calculations and stand dynamics resemble eco- logical modeling developed from forest stand dynamics. It can be challenging, then, to deter- mine where the bridge between rural and urban stand dynamics occurs in modeling. This presents the very real question about the appli- cation of ecological models in rural urban forests and their usefulness for rural municipalities. Through ecological models, we can estimate ecosystem ser- vices provided by component trees and roughly appraise their value. Through understanding site location and limitations, species risk profiles, and specimen-specific condition, we can also generate reproduction value of the urban forest as a whole. Collecting the parameters required to implement these ecological models comes at a huge cost, whether conducted by ground-based surveys or LiDAR. It is important that external consul- tants and practitioners within the municipality develop a working "problem statement" and understand management objectives. What do 28 CityTREES Figure 1. A rural community with an urban forest that has a high density of

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