Pacific Island Ecosystems at Risk (PIER)

  [   PIER species lists  ]   [   PIER home  ]

Ilex aquifolium
L., Aquifoliaceae
Click on an image for links to BIGGER PICTURES


Present on Pacific Islands?  yes

Primarily a threat at high elevations?  yes

Risk assessment results:  High risk, score: 17 (Go to the risk assessment)

Common name(s): [more details]

English: English holly, European holly, holly

French: houx commun

Spanish: muerdago

Habit:  tree

Description:  "Evergreen shrubs or small trees 2-10 m tall.  Leaves dark green, thick, glossy, ovate or elliptic, 5-12 cm long, 2.5-5.5 cm wide, glabrous, margins usually thickened, undulate, regularly or irregularly toothed, the teeth stiff, spreading, spinose, rarely entire.  Flowers fragrant, in fasiculate cymes along previous year's growth, up to ca. 1 cm long, peduncles 0.3-0.5 cm long; calyx lobes 4, deltate, ca. 1.5-2 mm long; corolla lobes ca. 4 mm long; ovary 4-celled.  Fruit bright red, 8-10 mm in diameter" (Wagner et al., 1999; pp. 222, 224).

Habitat/ecology:  "Forests, forest edges, scrub- and woodland.  In the native range, the plant occurs in woods, hedges and scrub.  Numerous cultivars and hybrids have been developed.  The plant forms dense thickets on the floor and on trees that change the structure of invaded forests by adding a tall and species-poor shrub layer.  Native plants are impeded in their growth and regeneration"  (Weber, 2003; p. 212).  "Dominates the tall shrub layer in moist, nutrient-rich sheltered bushland, creating deep shade in which native species can neither grow nor germinate, changing the environment"  (Weeds of Blue Mountains bushland).  Prefers acid, sandy or gravelly loam soils (Csurhes & Edwards, 1998; p. 111).

In Hawai‘i, "occasionally cultivated and now naturalized at the edge of degraded wet forest, 1,860 m" (Wagner et al., 1999; pp. 222, 224).

Propagation:  Seed, spread by birds (Wagner et al., 1999; pp. 222, 224).  "Holly also spreads by suckering and layering"  (Weeds of Blue Mountains bushland).

Native range:  "Southern and western Europe, northern Africa, and western Asia, widely cultivated" (Wagner et al., 1999; pp. 222, 224).

Presence:

Pacific
Country/Terr./St. &
Island group
Location Cited status &
Cited as invasive &
Cited as cultivated &
Cited as aboriginal introduction?
Reference &
Comments
Chile (offshore islands)
Juan Fernández Islands
Isla Más a Tierra (Robinson Crusoe Island) introduced
invasive
cultivated
Atkinson, Rachel/Sawyer, John (2011)
State of Hawaii
Hawaiian Islands
Hawai‘i (Big) Island introduced
invasive
cultivated
Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 222, 224)
Voucher cited: Herbst 8846 (BISH)
State of Hawaii
Hawaiian Islands
Maui Island introduced
invasive
Wagner, Warren L./Herbst, Derral R. (1995) (p. 15)
East Maui. Voucher cited: Tanabe 37 (BISH)
Nauru
Nauru Island
Nauru Island introduced
cultivated
Thaman, R. R./Fosberg, F. R./Manner, H. I./Hassall, D. C. (1994) (p. 94)
Ilex sp.; voucher cited: Hassall 164 (SUVA)
Pacific Rim
Country/Terr./St. &
Island group
Location Cited status &
Cited as invasive &
Cited as cultivated &
Cited as aboriginal introduction?
Reference &
Comments
Australia
Australia (continental)
Australia (continental) introduced
invasive
Csurhes, S./Edwards, R. (1998) (p. 111)
South Australia, Tasmania, Victoria
Australia
Australia (continental)
Australia (continental) introduced
invasive
U.S. Dept. Agr., Agr. Res. Serv. (2013)
Australia
Australia (continental)
New South Wales introduced
invasive
Csurhes, S./Edwards, R. (1998) (p. 111)
Canada (British Colombia)
Province of British Columbia
Canada (British Columbia) introduced
U.S. Dept. Agr., Nat. Res. Cons. Serv. (2013)
New Zealand
New Zealand
New Zealand (country) introduced
invasive
Webb, C. J./Sykes, W. R./Garnock-Jones, P. J. (1988) (p. 143)
"Scrubland and forest".
United States (west coast)
United States (west coast states)
USA (Oregon) introduced
U.S. Dept. Agr., Nat. Res. Cons. Serv. (2013)
United States (west coast)
United States (west coast states)
USA (California) introduced
U.S. Dept. Agr., Nat. Res. Cons. Serv. (2013)
United States (west coast)
United States (west coast states)
USA (Washington) introduced
U.S. Dept. Agr., Nat. Res. Cons. Serv. (2013)
Also reported from
Country/Terr./St. &
Island group
Location Cited status &
Cited as invasive &
Cited as cultivated &
Cited as aboriginal introduction?
Reference &
Comments
Canada (except British Colombia)
Canada
Canada (country) introduced
U.S. Dept. Agr., Nat. Res. Cons. Serv. (2013)
Ontario
United States (continental except west coast)
United States (other states)
United States (other states) introduced
U.S. Dept. Agr., Nat. Res. Cons. Serv. (2013)
Virgiania

Control: 

Physical:  "Small plants and seedlings are pulled or dug out, the roots must be removed".

Chemical:  "Freshly cut stumps should be treated with  glyphosate herbicide, otherwise the species will resprout.  Fruit-bearing plants should be removed first to prevent seed dispersal"  (Weber, 2003; p. 212).

"1. Swab stumps (all year round): cut down and paint freshly cut stumps with glyphosate (200ml/L) or Tordon Brushkiller (200ml/L). Dispose of cut material at refuse transfer station.
2. Bore and fill (spring-summer)): 1 downward angled hole every 5-10 cm around the trunk, 1.5 ml per hole Tordon Brushkiller (undiluted).
3. Frilling (all year round): With a sharp chisel or axe, make a deep cut into the sapwood at 5 cm intervals around the base of the tree, taking care not to ring-bark the plant. Immediately saturate the cuts with 1.5 ml of Tordon BK (undiluted) or glyphosate (200ml/L)"  (Weedbusters New Zealand).


Need more info? Have questions? Comments? Information to contribute? Contact PIER! (pier@hear.org)

  [   PIER species lists  ]   [   PIER home  ]

This page was created on 10 MAY 2005 and was last updated on 1 SEP 2012.