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OTHER INVASIVE PLANTS now common or threatening our area.
This list is not comprehensive, but begins to mention some of the plants which are proving most troublesome in our area.

Glossy Buckthorn (European Buckthorn) (Ramnus frangula)

identification
deciduous shrub, reaching height of 23'
leaves: alternate, glossy, 1-3 " long, oblong, smooth (wavy) margins
flowers: yellowish-green, five petals, in umbrels, bloom continuously during summer
seeds: red when immature, black on ripening
bark: brown/green, smooth, raised vertical lenticels; if trunk is cut, wood is orange.
habit prefers wet areas, but will grow in any disturbed site

control cutting will cause resprouting; so cuttings must be repeated. Cut in late summer or fall, and instantly paint cut surface with Roundup.   Girdle tree (4" wide strip, cut deep) and paint surface with Roundup in late summer or winter.  Hand-pull small seedlings; trees up to 2" diameter can be pulled with a weed wrench.

where to find it
Hanover: Balch Hill, Trescott Road (water company land) Mink Brook 
Lebanon: Etna Road, and near I-89 interchange #18 
Norwich: near Montshire, a little on Bill Ballard Trail
can be found all along the Connecticut River
 

Garlic Mustard (Alliaria petiolata)
 

identification
cool season biennial of 1-3 feet in height; sturdy white taproot ;  plants can reach a density
of 20,000 seedlings / square meter
flowers: white, cross-shaped and growing in clusters; blooms late spring, early summer; flowers appear in the plant's second year 
seeds: in slender, elongated pods, average 800/plant; vigorous plants may have 6000 seeds; which can sprout in first year 
leaves: garlic odor when leaves are crushed; the leaves of first year plant are rounded with teeth, growing in low rosette; second year plants have  alternate heart-shaped toothed leaves. 
habit forest edge and roadsides; tolerates deep shade and full sun; often found in floodplains 

control hand pull before seeds set in spring.   Roundup for dense populations,  especially effective for first year plants. 

where to find it 
Manchester NH: common on the road to the airport. 
Plainfield NH:  River Road  
Hanover NH:  Recently appeared at construction site on Buck Rd (near hay bale) 
Thetford, VT:  Geary Road

Shrub Honeysuckles

  • Tatarian Honeysuckle (Lonicera tatarica
  • Morrow Honeysuckle (Lonicera morrowii) and their hybrids 
identification
upright, coarse deciduous shrubs; up to 16' height 
branches:: wide spreading; older branches are hollow (to distinguish from native honeysuckle shrubs) 
leaves: opposite, simple, oval to oblong shape, 1 - 2.5 " long 
flowers: numerous, in pairs on slender stalks, tubular with deeply lobed petals 
seeds: fruits have many seeds;  berries are  red, orange or yellow
to distinguish the varieties: Tatarian: smooth hairless leaves, pink or white flowers.  Morrow has downy leaves, white flowers which turn yellow.
habit abandoned fields and pastures; edges of forest and wetlands; tolerate a variety of moisture and shade levels, prefer sun 

control small plants can be pulled easily, as roots are shallow. Cut stems of large plants in late summer, cut new sprouts.  If done in late summer, or on warm winter day,  cut stems can be painted with Roundup, if done at once to prevent resprouting.  Plant can be pulled up with weed-wrench.

where to find it
Roadsides, wetlands throughout Upper Valley.  Appearing in woodlands near towns. In many places it is the dominant shrub on the Connecticut River 
 

Japanese Knotweed (Polygonum cuspidatum)
 

identification
fast growing herbaceous perennial, 3-8' high forms dense patches 
stems:: stout, hollow bamboo-like 
leaves: broadly ovate 
flowers: tiny, greenish-white clusters all over plant in late summer 
seeds: wind dispersed, propagation: mainly by rhizomes, which may reach 45-50 feet 
habit sunny wetlands, marshes, roadside ditches; tolerates many soil types and a range of moisture conditions 

control avoid soil disturbance, to prevent it. It is not legal to use herbicides in wetlands.  Cut repeatedly in a season -- four times is best, accompanied by restoration planting.  Cutting procedure is required for several years. 

where to find it   common near urban wetlands throughout upper valley along road drainage ditches 
 

Common Reed (Phragmites australis)
 

identification
herbaceous, perennial grass, up to 15' in height stem:: stout 
leaves: long (up to 2 feet long) 
flowers: feathery plume purplish in July, tan or gray later 
propagation:: by seeds or underground rhizomes (which can spread 30 feet in
a year) 
habit sunny wetlands, marshes, roadside ditches; tolerates salt, grows in Ph range of 3.7 - 9.0, tolerates flooding 

control avoid soil disturbance, to prevent it.  Not legal to use herbicides in wetlands.  Cut over period of many years -- best time is before end of July 

where to find it  common near urban wetlands throughout upper valley, and along road drainage ditches (especially the interstates) 
 
 

Other alien invasives beginning to appear in our area

Burning Bush (Euonymus alatus) 
Japanese Barberry (Berberis thunbergii) 
Asiatic Bittersweet (Celastrus orbiculatus) 
Norway Maple (Acer platanoides) 
Autumn and Russian Olive (Elaeagnus umbellata) 
Multiflora Rose (Rosa multiflora) 
Black Swallow-wort (Vincetoxicum nigrum) 
Celandine (Chelidonium majus) 
Common Buckthorn (Rhamnus cathartica)

photo credits:  New England Wildflower Society