Tree · Pinaceae
Scots Pine
Pinus sylvestris
Tough, fast, and happy on poor, dry ground, the Scots pine asks for sun and little else.
Full sun
Every 7–14 days
USDA 2–7
30–60 ft · 9.1–18.3 m
Overview
The Scots pine is one of the most widely planted conifers in the world, a two-needled pine with flaking orange-red bark that lights up against a winter sky. Its evergreen needles come in twisted blue-green pairs, and the crown opens out and grows ragged with age, giving an old tree a windswept, characterful shape. It belongs to the Pinaceae family and ranges naturally across Europe and Asia, with a long history in North American landscapes and Christmas-tree fields.
What sets it apart is how little it asks. It grows fast, shrugs off cold down to -40°F (-40°C), and roots happily in dry, sandy, even fairly poor ground where fussier trees sulk. That toughness is also why it once filled so many yards and tree farms.
The catch is the pests. Pine wilt disease has knocked it out of the trade across much of the Midwest, and tip blight and a handful of insects can wear down a stressed tree. Plant it where wilt isn't established, keep it growing strongly, and it can stand for a very long time.
Care
The short version: full sun, well-drained sandy or loamy soil on the acidic side, and not much water once it's established. Feed rarely, prune only in dry weather, and give it the room a large tree needs.
Light
Scots pine wants full sun, the more the better. It puts up with almost no shade, and a tree crowded by taller neighbors grows thin, leggy, and weak.
Water
Once established it is drought tolerant and leans mostly on rainfall, even on dry, sandy sites. Water young trees through dry spells while the roots spread, then ease off. A soak every 7 to 14 days during establishment is plenty.
Soil
It thrives in well-drained sandy or loamy soil and is remarkably forgiving of poor, dry ground. It prefers things on the acidic side, somewhere around pH 4.5 to 7.0, but handles slightly alkaline soil without complaint.
Temperature
Cold is no obstacle. The tree takes temperatures from -40°F to 95°F (-40°C to 35°C), which is why it ranges so far north into zone 2.
Humidity
Ordinary outdoor humidity suits it fine, so there's no figure to manage. Air movement matters more than moisture in the air, since damp, stagnant conditions favor the tip blight that troubles this pine.
Feeding
This is a light feeder that rarely needs anything. Established trees do well with no fertilizer at all, and a single light balanced feed in spring is enough on the rare occasion growth looks poor.
Pruning
Keep it to a minimum. Take out dead, damaged, or diseased branches in dry weather only, since pruning when it's wet spreads Diplodia tip blight, and the tree does tolerate shearing when it's grown as a Christmas tree.
Repotting
Scots pine is a landscape tree and is rarely potted for long. In a container, roots circling the drainage holes, stunted new growth, or water running straight through tell you it has outgrown its home and needs the ground.
Size & spacing
This is a big tree, reaching 30 to 60 feet (9 to 18 meters) tall with a spread of 30 to 40 feet (9 to 12 meters). Give it that much open room, well clear of buildings and other trees, so the crown can develop in full sun.
When to plant
Scots pine is a cold-hardy tree for zones 2 through 7, so timing is about getting roots down rather than chasing a harvest. Plant in spring or fall while the soil is workable and rains are reliable, and let it settle in before the heat or hard cold arrives.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: spring or fall
- Harvest: Non-flowering conifer; produces gray to light brown cones about 3 in long. Often harvested as a Christmas tree.
Hardiness
USDA hardiness zones: 2–7
Temperature: down to -46°C
Troubleshooting
Most Scots pine trouble shows up in the needles and the new candles, and the worst of it spreads through pests and fungal disease. Learn to tell a serious threat like pine wilt from a treatable one, then act while it still helps. Match what you see below.
Whole branches browning and a tree dead within one season
This is almost always pine wilt disease, caused by a microscopic nematode that pine sawyer beetles carry from tree to tree. The needles fade to gray-green, then a dull yellow-brown, and the wood gives off little resin when you cut it. There is no cure, so a confirmed tree has to come down and be burned, buried, or chipped before the beetles move on to the next pine.
Fix:
- No cure exists once a tree is infected
- Promptly remove and destroy (burn, bury, or chip) dead and dying trees to eliminate beetle breeding sites
- Do not leave cut pine wood on site, as it harbors the beetle vector
Popcorn-like pitch on the trunk and branches snapping at the whorls
Those sticky masses are the work of the Zimmerman pine moth, whose larvae tunnel under the bark right where branches meet the trunk. The weakened crotches break, so a branch or even the top of the tree can snap off at a whorl. Prune out and destroy the infested wood, keep the tree growing strongly, and where the moth is a known problem spray the trunk in mid-April and again in mid-August to catch the larvae before they bore in.
Fix:
- Prune out and destroy infested, broken, or dying branches
- Maintain tree vigor with proper siting and watering
- Apply a registered insecticide trunk spray in mid-April and again in mid-August to target larvae before they bore in
Tiny white specks on the needles that scrape off
These are pine needle scale, little white armored insects that latch onto the needles and suck sap until the foliage looks bleached and thin. Hit the crawlers, the reddish nymphs that hatch in late spring, with horticultural oil or insecticidal soap, then repeat for the second generation in midsummer. Cut out and destroy any branches that are crusted over.
Fix:
- Treat crawlers (tiny reddish nymphs) with horticultural oil or an insecticidal soap in late spring
- Repeat for the second generation in midsummer
- Prune out and destroy heavily encrusted branches
Clusters of larvae stripping last year's needles in spring
The culprit is the European pine sawfly, whose grayish-green larvae feed shoulder to shoulder on the older needles while sparing the fresh tips. Hand-pick or prune out the clusters and destroy them, or knock the larvae off with a hard jet of water. If they are heavy, reach for an insecticide labeled for sawflies, since Bt does nothing against them.
Fix:
- Hand-pick or prune out clusters of larvae and destroy them
- Knock larvae off with a strong stream of water
- Apply an insecticide labeled for sawflies if defoliation is heavy (Bt does not work on sawflies)
New candles turning brown and stunted at the branch tips
This is Diplodia tip blight, a fungus that kills the fresh candles and leaves short, brown needles studded with tiny black fruiting bodies, sometimes spreading from wet-weather Dothistroma needle blight as well. Prune and burn the infected twigs and cones in dry weather only, and wipe your pruners with 10 percent bleach between cuts. Where the disease comes back every year, spray fungicide at bud break and through candle elongation.
Fix:
- Prune and destroy infected twigs, branches, and cones during dry weather only
- Sterilize pruners with 10 percent bleach between cuts
- Apply fungicide at bud break, half candle elongation, and full candle elongation where the disease is chronic
Toxicity
Good news for pet owners: Scots pine is a true pine and not poisonous to cats, dogs, horses, or livestock. The only thing to watch is the needles, which are sharp enough to prick a curious mouth, and the sticky sap, which can irritate skin or stain.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats Safe
Scots pine isn't poisonous to cats. The only real worry is the sharp needles, which can prick the mouth, and a little chewed greenery may bring on a brief bout of vomiting before things settle.
Dogs Safe
A dog can mouth the needles without being poisoned. Sticky sap and stiff needles may cause mild irritation, and a big mouthful of foliage can upset the stomach for a short while.
Horses Safe
Horses are fine around Scots pine, unlike ponderosa and a few of its relatives. There's nothing to watch for beyond the scratch of the needles themselves.
Rabbits Safe
The needles and bark hold no toxin for rabbits, and pine is sometimes offered as a gnawing branch. Make sure any wood comes from untreated, unsprayed trees.
Livestock Safe
Cattle, goats, and sheep can browse Scots pine without the pine-needle abortion tied to ponderosa pine. Grazing animals generally leave the prickly foliage alone anyway.
Birds Safe
Birds are in no danger from this pine. Many actually shelter in the dense crown and pull the seeds straight from the cones.
People Safe
Scots pine poses no poisoning risk to people, and the inner bark and needles have a long history of use in teas. The needles are sharp, so handle young children's contact with care.
Sharp needles and sticky sap can cause mild mechanical irritation; sap may stain. No special handling required beyond normal care.
Varieties
Most Scots pines sold are the straight species, but a few selected forms turn up for specific looks. These are the ones worth knowing by name.
Fastigiata
A narrow, columnar form that grows straight up like an exclamation point, perfect when you want a tall vertical accent in a tight spot.
Watereri
A slow dwarf that tops out around 10 to 12 feet, carrying stiff, twisted blue-gray needles over bark that flakes away in orange-tinged scales.
Glauca
Chosen for its deep blue-green needles, the bluest cast of any common Scots pine.
How to propagate
Scots pine is grown almost entirely from seed, with grafting reserved for the named forms that won't breed true.
SeedModerate
Sow stratified seed in spring. · 2 to 3 years to a sturdy sapling
Almost every Scots pine you meet was grown from seed. The cones take two years to ripen, and the seed needs a cold, moist spell before it will sprout, so sow it in spring after stratifying. Give it 2 to 3 years to build into a sturdy sapling.
GraftingDemanding
Late winter, onto seedling rootstock · 1 to 2 years
Named forms like Fastigiata and Watereri won't come true from seed, so growers graft them. The work is done in late winter onto seedling rootstock, and a successful union knits and takes hold over the next 1 to 2 years.
Myths
Scots pine needles cause abortion in pregnant animals.
Pine-needle abortion is a real problem, but it's tied to ponderosa pine and a few close relatives whose isocupressic acid affects pregnant cattle, not cats, dogs, or horses. Scots pine is not the species involved, and the ASPCA even lists ponderosa pine itself as non-toxic to dogs and cats.
Scots pine is an invasive species and should never be planted in North America.
The USDA Forest Service rates it noninvasive in North America, even though it has naturalized in parts of the Northeast and Great Lakes. What has really thinned it out of the landscape trade is pine wilt and other pests, not any tendency to take over.