Vol. 51—1997 - NorthEastern Weed Science Society

16
cherry (Pnmus se otina ranks fourth in relative abundance, and occupies 27.5 percent of the home sites. Pnmus serotina, a
successional spec es, has a low relative dominance value of 2.7.
Other i
(Table I). These
importance.
portant trees at urban home sites are red oak. white oak( Quercus alba) and scarlet oak Quercus coccinea)
aks rank two, three, and four respectfully in relative dominance and two. four and eight respectfully in
Trees pl ted at the home sites including exotic ornamentals, North American species not native to the New York City
region and native species have been placed in a separate table, Table 2. Dogwood, a native species, is the most abundant tree,
occurring at near y half of the home sites, Pin oak (Quercus palustris), a native species, ranks second in density and frequency.
Pin oaks are co only planted along city streets in the northeastern United States. Canadian hemlock (Tsuga canadensis), a
species native to orthern Queens 0 has the second highest density, yet ranks eighth in frequency (percent home-sites occupied).
The aforernentio ed data reflects the use ofTsuga canadensis} as a hedge-row tree. Homeowners plant T. canadensis along
property bound ies to provide privacy: the low frequency values indicate that few people at Jamaica Estates plant Canadian
hemlock on their property. All hemlocks observed were heavilv infested with the woolly adelgid, and are declining.
Two ex tics. Japanese maple (Acer palmatum) and Norway maple (Acer platanoides) have been planted at
approximately 0 e quarter of the home sites. Ten species are represented by only one or two trees (Table 2).
COMPARISONS WITH OTHER URBAN STUDIES
Urban borescent vegetation has not been intensively studied 3. The few studies of urban vegetation within or near New
York City includ those of Greller 0, Lefkowitz and (~reller 8, Airola and Buchholtz' Stalter 11 and Stalter and Serrao i1. Waldron
and Dyck 13, Do ey et al. 3 , Schmid 10 and Lawson er al 7 have examined lot locations of trees and shrubs in an urban
environment
Schmid 10 researched urban arborescent and frutescent vegetation in several Chicago, Illinois suburbs. The most
common trees fo d at home lots in Schmid's study were elm, silver maple. ash, Norway maple, hawthorn, and bur oak. Schmid
compared the ve etation of five neighborhoods reflecting socioeconomic factors on vegetation. He reported that older, wealthier
suburban neighb rhoods tended to have dense plantings of trees and shrubs. while those in urban areas were more open reflecting
differences in ag and socioeconomic status of the neighborhoods.
Lawso
Wisconsin. In t
reference. Ulm
et al, 7studied sixty-five lots in 1971 and 1972 in Nakoma Woods. an urban neighborhood in Madison.
is study, which is comparable to the present study, trees were mapped and trunk diameters measured for future
americana, Quercus alba (25.7) and Quercus velutina (11.3) ranked one. two, and three in relative dominance.
Not s risingly, there is a 'vide range in dominant species in urban locations that reflect climate. soils
and pre-existing egetation. Human factors such as homeowner preference also accounts tor differences in species composition,
especially differ nces in the numbers, frequency, and kind at home sites. Socioeconomic status may also account tor vegetation
differences. 3.1 0
e many large trees at both the home sites and at a nearby New York City Park. Alley Park. including some
individual trees ith a DBH greater than 100 em. (Figure 1). The home sites have a low percentage of native trees in the two
smallest size cla ses as few invading trees at the home sites are permitted to grow to maturity. Successional species such as
Pnmus serotina re generally found along property boundaries or on steep slopes where lawns are nonexistent or poorly
maintained. By ontrast, many trees are reproducing in Alley Park and are well represented in all size classes.
The ar orescent composition of the urban arborescent ecosystem at Jamaica Estates is unique as it is similar to that
found in nearby lley Park today and was similar to the forest of northern Queens County eighty years ago 6 and that of the
precolonial tore t in northern Queens. By comparison. studies by Dorney et al. 3, Schmid 10, and Waldron and Dyck I3report a
distinct type of ban forest on city lots. one that differs from nearby regional forests.
The de eloping urban forest at Jamaica Estates is approaching a post-developmental stage, with the death of relic trees
and their rep lac ment by planted trees. especially non-native species. The transition to a forest of non-native species may be a