Pinus flexilis
Limber Pine
Pinaceae
ExpandHabitat
- zone 4 to 7
- Rocky Mountains of Western U.S.
Habit and Form
- evergreen needle conifer
- 30 to 50' medium-sized tree
- about half as wide as tall
- dense, pyramidal when young
- when mature, develops as flat-topped broad crown ascending
Summer Foliage
- needles in 5's
- needles 2.5 to 3.5" long, dark bluish-green
- needles slightly curved or twisted
- persisting 5 to 6 years; branches often covered with needles from tip to trunk
Autumn Foliage
- same as summer foliage
Flowers
- monoecious
- male flowers clustered
- female flowers solitary or in 2's or 3's
Fruit
- 3 to 6" long, resinous, light brown cones
- appear fat and hefty
Bark
- young bark is smooth, greenish gray
- older bark is rough, blocky and scaly
- older bark is dark gray
Culture
- best in full sun
- more tolerant of salt spray on the foliage than other 5-needle pines
- said to be better adapted to dry soils and wind than P. strobus
- prefers moist, well-drained soil
Landscape Uses
- specimen
- as a screen
- in small groupings
Liabilities
- slow to medium growth
- relatively trouble free
ID Features
- often confused with Pinus strobus
- needles in 5's
- needles held up to 6 years; needles often tip to trunk on branches
- needles without serrations on margin like Pinus strobus
- stems, although flexible, are noticeably stouter than Pinus strobus
- flexibility of stems NOT a reliable ID feature
Propagation
- cold stratified seed, 1 to 3 months at 35-40oF
- cultivars grafted
Cultivars/Varieties
'Glauca' - This is an umbrella term for all selections with bluish-green foliage. These are among the most common forms of the species in commerce.
'Glauca Pendula' - This is a prostrate, vigorous plant with bluish needles and spreading habit. It can be allowed to grow as a groundcover or staked up as a small tree.
'Glenmore Dwarf' and 'Nana' - These are both slow-growing, dense bushy forms with short blue-green needles.
'Extra Blue' - This is a standard size selection with very good blue needle color and a pyramidal habit.
'Vanderwolf's Pyramid' - Perhaps the most popular selection at specialty nurseries, this selection grows with a broad, upright pyramidal habit. The needles are a bright blue-green color.