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Contracting the municipal tree care operation can generally handle specialized tasks more efficiently. It offers greater managerial/technical expertise. Contractors have the ability to manage their workforce more effectively. They can respond to crisis situations more rapidly and can downsize when no longer needed. Contracting only works well when it is functioning under properly trained customer supervision, well written specifications, good contract administration, competition and honesty.

The ISA Tree Valuation Guide is the most widely used method to determine the monetary values of amenity plants. Variables used to arrive at an appraisal are divided into subjective and objective classes and are critically examined. Each of the four factors: size, species, condition and location used to determine the final value of a plant are discussed. Suggestions and recommendations are made to improve the evaluation process and the individual appraiser.

Methods are discussed which illustrate ways data from properly planned street tree inventories can be used to create an urban tree management program, to aid in obtaining programmatic increases, to help a program in which survival is threatened, to protect from budget cutbacks, to increase the efficiency of an existing program, and to provide information for public information and education.

Approximately one quarter of cities and counties in the United States contract for tree maintenance. This percentage is increasing. On the average, tree contracting saves about one-third when compared to in-house costs with no loss of quality. The reasons contracting is cost efficient are outlined. Problems with contracting can be avoided if several guidelines are followed. Unit, time and material, and lump sum practices are evaluated. Contracting will increase in the future because contractors are generally more efficient, cities will be faced with continuing budget problems, and there will be more opportunities for contractors, which will increase competition.

A 1983 survey of 329 cities to determine the level of municipal tree care in New Jersey resulted in a return of 34 percent. The largest obstacle to tree care was lack of funding. Tree care agencies in New Jersey spent just over 50 percent of their time on actual tree-related work activities. A greater percentage of larger cities have suffered budget reductions than did smaller ones. Most tree care is divided into the activities of removal, pruning, and planting. Most tree work is scheduled by requests from residents. Contracting for tree work is widely used and satisfies the needs of the cities. Shade tree ordinances and public tree bodies are widely used, but less so in larger cities. Nearly all trees for street planting are purchased from commercial nurseries and are similar in composition to what is being planted by other cities in the northeast United States.

Contracting for all types of government services has increased recently. Contracting can provide efficient low-cost, high-quality services if the contracting process is properly understood. Good specifications must be developed and enforced. Steps have to be taken to ensure competition and qualified bidders. The contract should be monitored to guarantee performance because the responsibility of getting the work done still remains in the hands of city officials even though a contractor does it.

A 1983 survey of 13 municipally-owned street and shade tree nurseries in the Northeast United States determined that the average nursery was slightly larger than 2 acres, contained 830 trees and had been in existence 20 years. Tree stock for municipal nurseries was obtained by direct purchase from commercial nurseries and is grown in the nursery for an average of 3 years before outplanting as a 1 Vi-I % inch diameter street tree. The average initial purchase price of a bare-root tree was $12.50, cost $.80 to plant it, $3.40 to maintain it each year and $4.80 to lift and prepare it for planting. The type and level of nursery maintenance varied by community.

Guidelines are developed for an in-service training program to increase the quality and quantity of production in a tree maintenance operation. The three major elements in a typical program of what to teach, preparation, and how to teach are explained. A typical job example in a tree maintenance operation is divided into two areas of theoretical and practical material necessary to perform it.

Due to cutbacks in local sources of funding for urban tree maintenance activities, urban tree managers may become more reliant on federal funding grants. The need for information regarding the grant process was desired by a high percentage of surveyed urban tree managers. The sources of information about federal grants and the general process of writing and applying for them is summarized to enable tree managers to be in a more competitive position if outside funding is sought.

Girdling roots were examined on 336 street-side mature Norway maple trees [Acer platanoides) in Ann Arbor, Michigan. Most ot the girdled trees were girdled by multiple, shallow, subsurface roots. There was no association between girdled trees and narrow tree lawns. Most of the trees were not girdled severely. There did not appear to be any significant effects on crown characteristics attributable to root girdling.

Increment cores were taken from a random sample of 617 trees in Central Park in 1983-84. On the average just over 16 percent of the trees cored had stem decay. The percentage of trees with stem decay varied by species and increased by diameter class. There is a high degree of association in the sample between trees with stem decay and trunk abnormalities such as bark wounds and longitudinal cracks.

Increment cores were taken from 1,014 trees along streets in central New Jersey and in Central Park, New York in 1983-84. Of the trees cored, 142 (14.4 percent) had stem decay. A greater number of park trees had stem decay than did street trees (16.2 vs. 12.6 percent, respectively). Honeylocust (Gleditsia sp.) was the least affected by decay. Linden (Tilia sp.) was the most affected. Ginkgo [Ginkgo biloba), considered to be highly tolerant to urban conditions was seriously affected with 17.8 percent of the stems sampled having decay. Stem decay and the potential hazard caused by it should be carefully considered by the urban tree manager.