Spontaneous Urban Vegetation (aka Invasive Species)
Hairy Bittercress, Cardamine hirsuta
Place of Origin: Eurasia
Introduced: TBD
Life Form: winter or summer annual, wild relative to Arabidopsis thaliana
Seed Dispersal: seed pods – by explosive gravity
Ecological Function: Disturbance-adapted colonizer of bare ground
Princess Tree, Paulownia tomentosa
Place of Origin: temperate East Asia
Introduced: 1844
Life Form: deciduous tree
Seed Dispersal: winged seeds – by wind and water
Ecological Functions: Heat reduction in urban areas; tolerant of roadway salt and compacted soil; erosion control on slopes; soil building on degraded land.
p. 102
Oriental Bittersweet, Celastrus orbiculatus
Place of Origin: northeast Asia
Introduced: 1860′s
Life Form: deciduous woody vine
Seed Dispersal: 3-valved capsules covered by arils – by animals (long distance by birds), water, and humans
Ecological Functions: Food and habitat for Wildlife; erosion control on slopes
p. 58
Dandelion, Taraxacum officinale
Place of Origin: Eurasia
Introduced: with early European settlers, including Mayflower
Life Form: herbaceous perennial
Seed Dispersal: seed-bearing parachutes – by wind
Ecological Functions: Distrubance-adapted colonizer of bare ground; food for wildlife.
p. 170
Tree-of-heaven, Ailanthus altissima
Place of Origin: central China
Introduced: early 1800′s
Life Form: deciduous tree
Seed Dispersal: winged samara – by wind
Ecological Functions: Extremely tolerant of stressful urban conditions including heat buildup, drought, air pollution, and road salt; important for slope stabilization and soil building on degraded land.
p. 104
Bittersweet Nightshade, Solanum dulcamara
Place of Origin: Eurasia and North Africa
Introduced: mid- 1800′s [2]
Life Form: trailing, semiwoody vine
Seed Dispersal: seeds inside fleshy fruit – by animals (especially birds) and gravity
Ecological Functions: Tolerant compacted soils; Food and cover for wildlife.
p. 106
Multiflora Rose, Rosa multiflora
Place of Origin: temperate East Asia
Introduced: early 1800′s via Europe
Life Form: climbing shrub
Seed Dispersal: seeds inside rose hips – by animals and gravity
Ecological Functions: Tolerant of roadway salt and compacted soil; food and cover for wildlife; erosion control for slopes.
p. 86
White Mulberry, Morus alba
Place of Origin: eastern Asia
Introduced: 1700′s
Life Form: deciduous tree
Seed Dispersal: seeds inside the fruit – by animals and gravity
Ecological Functions: Heat reduction on paved areas; tolerant of roadway salt and compacted soil; food and habitat for wildlife; erosion control on slopes.
Wild Carrot, Daucus carota
Place of Origin: Eurasia and North Africa
Introduced: before 1859
Life Form: herbaceous biennial
Seed Dispersal: seed spines – by attaching to animals and wind
Ecological Functions: Disturbance=adapted colonizer of bare ground; tolerant of roadway salt and compacted soil; food for wildlife.
p. 122
Mugwort, Artemisia vulgaris
Place of Origin: Eurasia
Introduced: Early date
Life Form: herbaceous perennial
Seed Dispersal: light seeds – by wind and water
Ecological Functions: Phytoremediation in degraded urban landscapes (absorbs the heavy metals zinc, copper, lead, and cadmium and binds them to organic matter); tolerant of raod salt and compacted soil; erosion control on slopes; soil building on degraded soil.
p. 134
Shephard’s Purse, Capsella bursa-pastoris
Place of Origin: Europe
Introduced: Earlier than 1672
Life Form: winter annual
Seed Dispersal: light seeds – by wind, animals, water and humans
Ecological Functions: Disturbance-adapted colonizer of bare soil.
p. 184
Japanese Knotweed, Polygonum cuspidatum
Place of Origin: temperate East Asia
Introduced: 1870′s
Life Form: herbaceous perennial
Seed Dispersal: winged perianth – by wind, animals (including birds), insects, and water
Ecological Functions: Tolerant of road salt and compacted soil; erosion control on slopes; stream and river bank stabilization; soil building on degraded land.
On Feb 3, 1999, Executive Order 13112 was signed establishing the National Invasive Species Council.
Federal Noxious Weed List >>
Unless otherwise noted data from Del Tredici, Peter, Wild Urban Plants of the Northeast: A Field Guide, Cornell University Press, 2010. [except Seed Dispersal data]
[2] Voss, Edward G. 1996. Michigan flora. Part III: Dicots (Pyrolaceae–Compositae). Bulletin 61. Bloomfield Hills, MI: Cranbrook Institute of Science; Ann Arbor, MI: University of Michigan Herbarium. 622 p