Study Guide Ch. 8 Plants, Parks, and Sports Flashcards
Questions related to vegetation will simply address how evergreen and deciduous plants are used in different applications (e.g., evergreen plants are superior for blocking wind, and deciduous trees will allow areas to receive sunlight in the winter), as well as the scalar differences between grass, shrubs and trees (e.g., trees can block sight lines, whereas low shrubs will not)
Will require you to pay attention to the placement of trees on a site, specifically as it relates to safety and climate
Ecological benefits
Vegetation sequesters CO2, filters air, removes pollutants, reduces erosion and improves water quality while also providing habitat and food opportunities for wildlife
Human benefits
Plant materials can be used to mitigate the negative effects of wind, harsh light, temperature and humidity on site, thereby increasing comfort for human users.
Heat island effect
Vegetation can reduced the heat island effect when it replaces hardscape surfaces, or shades hardscape from the sun
Scale
Larger, taller, and wider tree canopies produce more shade than those with lesser dimensions
Seasonal impact
Deciduous trees provide shade in the summer when the sun is most intense, and (by dropping their leaves) allow beneficial heating from the sun in the winter
North
Windbreaks should be located on the north side of a site given that northwestern slopes receive cold winter winds and northern slope are coldest in the winter
South
Southern slopes receive the most sun in winter months, and buildings are often oriented toward the south to take advantage of passive heating. If trees are located to the south of a building, deciduous trees should be selected given that they do not produce shade in the winter months
East
Vegetation placed to the east of site features generally had little impact on the site microclimate
West
West-facing site features receive the most heat during the summer. Trees should therefore be located to the west of any feature or building that requires shade in the summer.
Windbreaks
Vegetation for windbreaks
Woody, evergreen vegetation is best suited for windbreaks and air funneling, and various sources state that evergreen windbreaks should be at least three plants deep to be effective (and deciduous windbreaks ten plants deep).
Note that taller herbaceous plantings such as grasses have little impact on wind, and deciduous plants do not block wind during the winter.
Windbreak location
Vegetation should be placed in the direct path of the prevailing wind, with adequate spacing from a structure to provide insulating “dead air”. Windbreaks should be placed at least half of their height away from the face of the structure to provide sufficient dead-air space.
Windbreak scale
All other things being equal, taller and thicker windbreaks provide superior protection from wind
Be familiar with general characteristics and programming requirements of parks, as well as the differences between parks and parkways
Neighborhood parks
Should be centrally located in the neighborhood that they serve and connect to broader circulation networks (especially sidewalks) to facilitate ease of access and encourage use.
Can range in size from 1 acre (typically existing parks in urban areas) to up to 10 acres, but - as a general rule - neighborhood parks will be around 5 acres in size and should be at least 3 acres in size if possible.
Should be contiguous and uninterrupted by roads or other barriers, including wetlands, rivers and lakes
Sites not suitable for other forms of development are also not suitable for use as neighborhood parks