Data provided by the participants of the Consortium of California Herbaria

View additional distribution information on the Jepson eflora

Island Ironwood (Lyonothamnus floribundus) is a native tree that grows in Southern and Central California, primarily in the Channel Islands region. It tends to grow in rocky slopes, at elevations from 100-1600 feet. Lyonothamnus is endemic to the Channel Islands of California, where it grows in the chaparral and oak woodlands of the rocky coastal canyons.

This is a tree growing up to 15 metres (49 ft) tall with peeling reddish gray or brown bark. The evergreen leaves are shiny, dark green with lighter undersides, and borne on short petioles. The two subspecies have leaves of different leaf shapes. Ssp. asplenifolius (Santa Cruz Island Ironwood) has incised, fern-like leaves and is the more commonly available in horticultural form. Ssp. floribundus (Catalina Island Ironwood) has smooth, undivided leaves and is seldom seen in gardens. The inflorescence of both is a cluster of woolly white flowers with many short, whiskery stamens. The fruit is a pair of hard follicles.

Plant type

Tree

Size

25 - 50 ft Tall
15 - 24 ft Wide

Form

Upright Columnar

Growth rate

Fast

Dormancy

Evergreen

Fragrance

None

Calscape icon
Color

Cream, White

Flowering season

Spring, Summer

Special uses

Bank stabilization, Hedge

Sun

Full Sun

Water

Low

Summer irrigation

Max 1x / month once established

Cold tolerance

Tolerates cold to 22° F

Soil drainage

Fast, Medium

Soil description

This tree is tolerant of a variety of garden soils as long as drainage is reasonably good.
Soil PH: 5.0 - 8.0

Propagation

For propagating by seed: Place seeds in about 6 times their volume of 140°F wa ter then let cool about 45 mins. before sowing ( Maunsell Van Rensselaer correspondence to Howard McMinn 1947). No treatment. gives fair germination.

Site type

Rocky slopes

Plant communities

Chaparral

Caterpillars
Butterflies

Butterflies and moths supported

1 confirmed and 0 likely

Confirmed Likely