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Community involvement is critical for the continued vitality of the urban forest. To encourage this involvement, an understanding is needed of what promotes shared stewardship as well as of different cultural perspectives regarding trees. A survey of the general public in 109 large metropolitan areas across the continental U.S., a culturally and ethnically diverse group, was conducted. Two thousand adults were surveyed to assess the extent of their childhood experiences with nature, their current attitudes toward urban forests, and their demographic backgrounds. Respondents were questioned particularly about their earliest experiences with nature and their current understanding and appreciation of the urban forest. Other researchers have examined the relationship between childhood contact with nature and attitudes toward nature among professionals in environmental fields, but this relationship has not been explored in the general public. Correlations between survey respondents' memories of childhood contact with nature, their current perceptions of the urban forest, and the influence of their cultural and ethnic backgrounds will be presented. For example, respondents who reported very easy access to nature as children were likely to agree strongly that trees should be planted in business districts to reduce smog. Results from this survey may be applied in programs to teach children about trees and gardening, thus better tailoring these programs to engender future appreciation for the urban forest. Raw data from this survey will be made available to other researchers.

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Urban areas have average annual temperatures 2–3°C warmer than surrounding rural areas, with daily differences of 5–6°C common. A suggested reason for this temperature difference is the extensive use of concrete, asphalt, and other building materials in the urban environment. Vegetation can moderate these temperatures by intercepting incoming radiation. The influence of vegetation patterns on the magnitude of urban and micro-urban “heat islands” (UHI and MUHI, respectively) is compared for several cities including Houston, Austin, College Station, and Ft. Worth, Texas; Huntsville, Ala.; and Gainesville, Fla. Temperatures for all cities studied were greatest in the built-up areas and dropped off in suburban areas and adjacent rural areas. In Houston, surrounding rice fields were 3–5°C cooler than urban areas. Heavily built-up areas of Austin were 2–4°C warmer than parks and fields outside of the city. In all of the cities, large parks were typically 2–3°C cooler than adjacent built-up areas. Large shopping malls varied in nocturnal winter and summer temperature, with winter temperatures near door openings 2–3°C warmer, and summer daytime temperatures as much as 17°C cooler beneath trees. This effect seemed to persist at the microclimatic scale. Areas beneath evergreen trees and shrubs were warmer in the winter than surrounding grass covered areas. Video thermography indicated that the lower surfaces of limbs in deciduous trees were warmer than the upper surfaces. Overall, vegetation played a significant role, both at the local and microscale, in temperature moderation.

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This study evaluated the influence of social economic rank (SER) and neighborhood and park age on the composition and place of origin of trees in residential neighborhoods and embedded small urban parks in Phoenix, Ariz. During 2000 and 2001, trees were surveyed within an array of 16 residential neighborhoods and embedded small urban parks that spanned a range of socioeconomic rank (SER) and age. Parks were embedded within residential neighborhoods of similar density across three SER classifications, high, moderate, or low. Neighborhoods and parks ranged in age from about 1947 to 1997. Counts of all trees in each park were made and neighborhood tree composition was approximated by tree counts along four transects, distributed away from each park along streets in a northerly, easterly, southerly, or westerly direction, respectively. Transect widths extended about the depth of a front yard residence on both sides of the street. Park and surrounding neighborhood tree composition was calculated as total frequency (abundance) and taxa frequency (diversity) per hectare of landscape surface area. Tree abundance in parks was highest when surrounded by neighborhoods of high SER. Neighborhoods of high SER had greater tree diversity than neighborhoods of low SER. Distinct patterns of tree origin, dictated by both classifications of SER and age, were found. Overall, trees in residential neighborhoods and embedded parks tended to be indigenous to arid regions of North America, South America, Australia, south Asia, and China.

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Windbreaks are an essential part of rural and urban living in the northern Great Plains. They provide protection to crops and livestock from wind by modifying windchill factors, lowering soil erosion, and conserving soil moisture. Around farmsteads and cities, benefits include energy conservation, control of snow deposits, and added aesthetic values. In urban centers windbreaks are important as aesthetic screens, living snow fences, noise barriers, and sites of air filtration.

Tree establishment on the prairies can be challenging with low rainfall and cold winter temperatures. A windbreak demonstration program began in 1989 across the state of North Dakota. The demonstration program is a joint effort between local soil conservation districts, extension service, and 275 landowners. The demonstrations were designed to compare new and traditional tree establishment techniques. The program goal is to gather data from various demonstration sites and transfer the information to land owners, thereby increasing tree survival and establishment in windbreak plantings.

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Abstract

Factors affecting natural infestation of flowering dogwoods (Cornus florida L.) by the dogwood borer, Synanthedon scitula Harris (Lepidoptera: Sesiidae), were studied in an urban cemetery in Louisville, Kentucky. Two tree characteristics, severity of trunk wounding and exposure to sun, were most important in determining the probability of borer attack. Degree of crown dieback or color of bloom did not significantly affect the rate of infestation. There was no correlation between tree diameter and probability of attack, but height of attack sites increased linearly with increasing tree size.

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The Expressway Partnership (a project of the Chicagoland Chamber of Commerce's Gateway Green Committee) is an urban landscape project that promises to change the face of the city's expressways. The Morton Arboretum's Urban Horticulture Research Lab., with the support of ComEd (Excelon Corp.), since 2001 has been selecting, planting, and evaluating various cultivars of trees, shrubs, and ground covers in a search for the most suitable and sustainable plantings for the expressway environment. About 470 trees and shrubs were planted plus more than 10,000 groundcovers. In May 2002 these plants were visually evaluated and ranked from 1–5 with one being in excellent condition and 5 being dead. The control plants planted at Urban Horticulture Research Nursery at the Morton Arboretum had 100% survival. The survival rates for groundcovers were: Euonymusfortunei (Virginia Creeper) and Hemerocallis×daylily (day lily) had 80% to 90% survival rates, respectively. Pachysandra terminalis (Japanese spurge) plants died due to either de-icing salt sensitivity, or poor weed control. Syringa pekinensis (Peking lilac), as well as four Syringa cultivars, `President Grevy', `Summer Charm', `Charles Joly', and `James Mcfarlane', had a 100% survival rate. Survival rates for other plants were: Malus sargentii (Sargent crabapple) 93%; Robinapseudoacacia (black locust) ∼93%; Malus cultivars ∼75%; and Pinusbanksiana (jack pine) 75%. Cornussericea (red-osier dogwood) covered with 3 inches of mulch had a significantly better survival rate (90% to 100%) than the mulch treatment (60% to 80%). The growth and performance of other trees and shrubs will be also reported. This research will ensure sustainable and esthetic urban expressway plantings, while enhancing Chicago's stature as a significant urban landmark.

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Heightened awareness of ecological concerns have prompted many municipalities to promote water conservation through landscape design. In central Arizona, urban residential landscapes containing desert-adapted plant species are termed xeriscapes, while those containing temperate or tropical species and turf are termed mesoscapes. Research was conducted to ascertain landscape plant species diversity, tree, shrub, and ground cover frequency; landscape canopy area coverage; and monthly irrigation application volumes for xeric and mesic urban residential landscapes. The residential urban landscapes were located in Tempe and Phoenix, Ariz., and all were installed initially between 1985 and 1995. Although species composition of xeric and mesic landscapes was generally dissimilar, both landscape types had comparable species diversity. Mesoscapes had significantly more trees and shrubs and about 2.3 times more canopy area coverage per landscaped area than xeriscapes. Monthly irrigation application volumes per landscaped surface area were higher for xeriscapes. Even though human preference for xeric landscape plants may be ecological in principle, use of desert-adapted species in central Arizona urban residential landscape settings might not result in less landscape water use compared with mesic landscapes.

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Abstract

Man for centuries has had an appreciation of flowers made use of native plants, cultivated and selected more ornamental and exotic types, and improved food plants. But he has devoted relatively little research to the production of woody ornamentals -- trees and shrubs that have woody stems. The breeding of woody ornamentals, however, has gained momentum as a result of accelerated emphasis on beautification due to the population explosion and the aesthetic needs or urban sprawl.

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Abstract

A comprehensive study of new introductions of shade and ornamental trees adapted to the North Central United States has been underway at the Ohio Agricultural Research and Development Center, Wooster, since 1966. Goal of the IO-year research effort is to evaluate characteristics of each cultivar, paying special attention to identifying the suitability of each for planting in urban and suburban environments, along street and highway right-of-ways, and under utility lines.

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In a unique partnership. the University of Kentucky Dept. of Horticulture, the Cooperative Extension Service, and the Kentucky State Division of Forestry are teaming up to produce two training packages for “train-the-trainer” workshops throughout the state. The workshops will be open to people interested in urban/community trees and arboriculture.

The first training session will be held in 1993 and will cover five modules: 1) Designing the planting site to compensate for a disturbed environment; 2) Species selection for the existing site; 3) Scientific planting techniques; 4) Post-planting care: and 5) Integrated pest management.

The second training session will be held in 1994 and will cover the following topics: 1) Establishing a scientific management program for the urban forest; 2) Preparation and administration of grants: 3) Fund-raising and efficient use of volunteers; 4) Developing an urban tree inventory; 5) Recognition of hazard trees; and 6) Selecting quality nursery stock.

The training packages will consist of a written manual, videos, and slide sets. Training sessions are open to foresters, county agents, city planners, developers, and others in Kentucky who are interested in returning to their communities and training others on the topics covered.

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