Ilex crenata Thunb.

Japanese Holly

Category
Shrub

Similar Species May be confused with the following native and/or non-native species. Landscape Alternatives lists native horticultural substitutes	Buxus sempervirens Ilex vomitoria

Description

Stem

A small shrub with a very dense crown, Japanese Holly rarely exceeds 3 feet in height. Some varieties are more upright, and the native species is a small tree. Japanese holly twigs are slender, yellow-green, and often pubescent with small buds and leaf scars with 1 bundle scar. The bark is smooth, light greenish brown to gray.



Leaves

The evergreen leaves are alternate, simple, elliptical to obovate, and very small (1/2 to 3/4 inch long). The margin may be shallowly toothed on upper half or entire. Leaves are shiny dark green above, dull light green below.


Flowers

The flowers are dioecious (having the male and female reproductive organs on separate individuals of the same species), small (1/3 to 1/2 inch across), 4-petaled, and white with a pale greenish center. They appear in late spring.


Fruit

Fruits are round, black drupes, 1/4 to 1/3 inch in diameter. They ripen in early fall and persist into spring.


Life History

Ilex crenata is used in formal hedges, as specimen plants and in mixed borders. They are frequently used as neatly trimmed hedges along building foundations. Japanese Holly is often used for bonsai. The cultivar 'Sky Pencil' makes an interesting vertical accent for a small space or corner in the landscape, and a line of them could also be used for a screen or narrow hedge. Japanese Holly is quite similar to Boxwood (Buxus microphylla) and Yaupon Holly (Ilex vomitoria), and is used in the landscape in the same settings.

Habitat

Japanese holly prefers full sun or light shade. Some cultivars do better in full sun. It grows well in most soils (but does best in acidic soils) as long as they are not waterlogged.

Origin and Distribution

Introduced from Asia. USA (DC, DE, LA, NC, NJ, NY, OH, PA, WA)

Management Recommendations

Mechanical Controls

Seedlings and small plants can be hand-picked or dug out, though this soil disturbance can also create sites for further invasion. Cut branches must be disposed of properly (burned or composted) to ensure they don’t sprout into new plants.

Herbicidal Controls

To remove established shrubs, stems should be cut off at the base and disposed of properly, and then a general use herbicide such as glyphosate or triclopyr can be applied to the freshly-cut stump to prevent regrowth.