Southwestern White Pine
Pinus strobiformis
Southwestern White Pine (Pinus strobiformis) is a Colorado-native tree suited to the Colorado Front Range, rated "Recommended" on the 2024 Front Range Tree Recommendation List. It matures to about 50 to 70 ft tall and 25 to 30 ft wide, slow-growing, needs low to medium water, and prefers full sun.
Photos
- Photo 1: (c) Matt Berger, some rights reserved (CC BY)
- Photo 2: (c) CK2AZ, some rights reserved (CC BY), uploaded by CK2AZ
At a glance
Will it survive here?
- Hardiness zones
- USDA 3 to 7
- Water needs
- low to medium water
- Sun
- Best in full sun.
- Soil
- loam, sandy, well drained only
- Soil pH
- 6.0 to 8.2
- Hail tolerance
- high
- Wind tolerance
- high
- Salt tolerance
- moderate
How big, what shape?
- Mature size
- 50 to 70 ft tall and 25 to 30 ft wide
- Mature form
- Pyramidal
- Spacing / clearance
- ~30 ft of clearance
- Growth rate
- Slow
- Lifespan
- Long-lived
What it looks like, and when
- Foliage
- Evergreen
Who else benefits
- Pollinator value
- low
- Deer
- Not rated
- Colorado native
- Yes
- Native ecoregion
- montane
Also worth knowing
- Fire rating
- Ignitable (CSU): keep 30+ ft from the house, thinned
Common problems on the Front Range
- Mountain pine beetle in drought-stressed pines
- Pine wilt nematode (esp. Scots and Austrian pine)
- Pine needle scale
These are general tendencies for this group of plants on the Front Range, not a diagnosis. Many are stress-driven and preventable with good siting and watering. For a specific plant or an active problem, consult a certified arborist or your local CSU Extension office.
Planting & establishment
Water deeply every 7 to 10 days through the first 2 summers (less for xeric pines in heavy clay, they're prone to root rot). Winter water 1 to 2×/month October to March when soil is dry and unfrozen, evergreens transpire year-round. Year 3: taper to twice per month in summer; only during extreme drought thereafter.
Frequently asked questions
- Is Southwestern White Pine good for the Colorado Front Range?
- Yes, Southwestern White Pine is a well-suited tree for Colorado's Front Range, rated "Recommended" on the 2024 Front Range Tree Recommendation List.
- How big does Southwestern White Pine get?
- It matures to about 50 to 70 ft tall and 25 to 30 ft wide.
- How much room does Southwestern White Pine need?
- Give Southwestern White Pine about 30 ft of clearance from buildings, fences, and other trees so the mature canopy isn't crowded.
- What shape does Southwestern White Pine grow into?
- Southwestern White Pine typically grows into a pyramidal, conical outline that is widest at the base. This is the species' usual mature form, named cultivars (columnar, weeping, or compact selections) can differ, so check the specific cultivar.
- Is Southwestern White Pine hardy on the Front Range?
- Southwestern White Pine is hardy in USDA 3 to 7. The Colorado Front Range spans roughly USDA 4b to 6a, so it is well within range.
- How much water does Southwestern White Pine need?
- It needs low to medium water once established.
- How fast does Southwestern White Pine grow?
- Southwestern White Pine is a slow-growing tree. Growth rate depends on water and site conditions on the Front Range.
- How long does Southwestern White Pine live?
- Southwestern White Pine is long-lived, a multi-generational tree given good siting and care. Actual lifespan varies with site, water, and care.
- Is Southwestern White Pine native to Colorado?
- Yes. It is a Colorado native.
- Is Southwestern White Pine a good firewise plant near the house?
- Southwestern White Pine is listed by CSU Extension among the more ignitable plants, so keep it 30 or more feet from the house and keep it thinned and well maintained. This is general guidance based on CSU Extension Fact Sheet 6.305 (2025), not a guarantee that any plant won't burn, a well-irrigated, well-maintained plant is the goal. Follow CSU Extension defensible-space guidance and check with your local fire district before planting in the wildland-urban interface.
- Is Southwestern White Pine prone to pests or disease on the Front Range?
- Southwestern White Pine can be affected by mountain pine beetle in drought-stressed pines and other issues common to this group on the Front Range. These are general tendencies, not a diagnosis, many are stress-driven and preventable with good siting and watering. For a specific plant or an active problem, consult a certified arborist or CSU Extension.
