lilac chastetree USDA PLANTS Symbol: VIAG
U.S. Nativity: Exotic
Habit: Shrub or Subshrub
Vitex agnus-castus L.

Jump to: Images | Distribution Maps | Sources
Taxonomic Rank: Magnoliopsida: Lamiales: Verbenaceae
Native Range: S. Europe, W. Asia (REHD);

Appearance
Vitex agnus-castus is a sprawling shrub that grows from 10-20 ft. (3-6 m) and about as wide.
Foliage
The palmately compound leaves of Vitex agnus-castus are 3-4 in (7.6-10 cm) in diameter and with 5 to 7 lacelike leaflets. The foliage is aromatic and ranges from grey-green to dark green above and lighter underneath.
Flowers
Flowers are blue, lavender or white, about 1 in. (2.5 cm) across, five petals blunt at tip, arranged in spiral. It blooms in springtime.
Fruit
Vitex agnus-castus fruits are a globose drupe. Each fruit has four cells that usually contain one seed per cell.
Ecological Threat
Vitex agnus-castus is showing invasive tendencies in areas where it has been planted extensively in landscaping, as in Texas. It can now be found in limestone outcrops and dry creek beds throughout Central Texas.(1) The ’virtues’ listed by nurseries and gardeners indicate that the invasive potential for this plant may be high. Those characteristics include: “Easy to grow in any soil; can take of itself; survived six years drought unattended; hardly ever disturbed by pest or disease; and tolerant of salt drift.”(2) It does produce fertile seeds and readily seeds out into surrounding areas. Vitex agnus-castus should be listed as an EDRR (Early Detection & Rapid Response) species across the southern United States where it is warm enough for it to survive the winters.

Selected Images from Invasive.orgView All Images at Invasive.org


Foliage; An invasive plant in central Texas
Ronald F. Billings, Texas A&M Forest Service , Bugwood.org
Additional Resolutions & Image Usage

Flower(s); An invasive plant in central Texas
Ronald F. Billings, Texas A&M Forest Service , Bugwood.org
Additional Resolutions & Image Usage

Flower(s);
Karan A. Rawlins, University of Georgia, Bugwood.org
Additional Resolutions & Image Usage

Foliage;
Karan A. Rawlins, University of Georgia, Bugwood.org
Additional Resolutions & Image Usage

EDDMapS Distribution:
This map is incomplete and is based only on current site and county level reports made by experts and records obtained from USDA Plants Database. For more information, visit www.eddmaps.org
 


State(s) Where Reported invasive.
Based on state level agency and organization lists of invasive plants from WeedUS database.


Invasive Listing Sources:
Faith Campbell, 1998
Reichard, Sarah. 1994.  Assessing the potential of invasiveness in woody plants introduced in North America. University of Washington Ph.D. dissertation.