Pinus coulteri

Pinus coulteri (06/01/2013, Kew Gardens, London)

Position: Full sun

Flowering period: Spring

Soil: Moist, well drained

Eventual Height: 20m

Eventual Spread: 9m

Hardiness: 8b, 9a, 9b, 10a, 10b

Family: Pinaceae

Pinus coulteri is an evergreen tree with a broad open crown. Its green/ grey leaves are needle like, in bundles of three, up to 30cm long and 2mm thick. Its branches are horizontal to ascending. Its trunk may achieve a diameter of up to 1m. Its dark grey/ brown bark is furrowed with scaly ridges. Its monoecious light purple/ brown flowers are ovoid pollen cones, wind pollinated and up to 25mm long. Its orange/ brown fruit are  drooping seed cones, these are up to 35cm long, 15cm broad and have spines on each scale. Its cones mature after two years and are persistent on the tree. These are the largest pine cones of any Pine species.

Pinus coulteri, commonly known as the Coulter Pine, Big Cone Pine or Widow Maker (due to the potentially lethal nature of its cones when they fall), is native to the mountainous regions of the west coast of south west USA and north west Mexico. In its native habitat it grows on dry rocky slope and mixed Oak/ Pine woodlands.

The etymological root of the binomial name Pinus is derived from the Latin name for Pine tree. Coulteri is named after Thomas Coulter (1793 – 1843), an Irish botanist.

The landscape architect may find Pinus coulteri useful as an ornamental parkland tree. Once established this tree is drought tolerant.

Ecologically, Pinus coulteri seeds are attractive to some birds. Some birds feed on insects found in the bark of this tree.

The Royal Horticultural Society has given Pinus coulteri their prestigious Award of Garden Merit in 1993.

Pinus coulteri Leaf (06/01/2013, Kew Gardens, London)

Pinus coulteri prefers moist, fertile, well-drained soils. It tolerates most pH of soil. It will grow in nutrient poor soil. It dislikes poorly drained soils.

Pinus coulteri requires little maintenance.