Pinus pinea Seeds | Stone Pine
LATIN NAME: Pinus pinea
COMMON NAME: Stone Pine
Plant Profile
The change is architectural rather than accidental. While the tree is young it holds a dense, round crown; as it matures the leading shoot loses its dominance and the remaining branches extend on a near-horizontal plane, so the crown flattens and broadens. Older trees often have a forked trunk and bark that breaks into orange-tinted plates. Pruning is rarely needed.
The needles come in bundles of two, stiff and bright green and long enough to make a fringe around the shoot. The cones are large and rounded, and the seeds inside are the biggest thing the species has to offer: heavy, hard-shelled and, unusually for a pine, without a functional wing. A heavy unwinged seed cannot ride the wind; the crop is carried off and buried by jays and other crows, which cache far more than they recover.
Its nearest Mediterranean relatives are the Aleppo pine, the Turkish pine and the Canary Island pine, all of them narrow-crowned with small winged seed. The stone pine is a coastal and lowland tree of deep sand and poor, well-drained ground within reach of the sea.
The needles smell of alpha-pinene and limonene, and the trunk yields a resin once tapped and distilled in southern Europe.
Science & Biotechnology
The kernel has a distinctive fat: pinolenic acid, a fatty acid with an unusual double-bond arrangement found in pine nuts and studied for its effect on appetite signalling. Alongside it sit the more familiar linoleic and oleic acids, and the nut carries tocopherols that help keep the oil from turning rancid. Fresh kernels are also coated with a dark powdery film that is rubbed off during cleaning.
Uses & Benefits
The species is slow to give its crop. A cone that is pollinated in one season continues to swell through the next and only matures in the third, so a bearing tree can carry cones of three different ages at once. That long residence on the branch makes the nut harvest a patient business, and cones are gathered in winter and dried until the scales open.
Growing from Seed
The pine nut is the whole point of the cultivated tree. Kernels are eaten raw, toasted over vegetables, folded into stuffings and pounded with basil, garlic, cheese and olive oil into Genoese pesto. In Spain and Portugal the cones are gathered by hand with long poles and spread out to dry until the scales separate and release the seed.
Sow the large seed in deep containers, because the root runs down fast and a shallow tray produces a bent taproot. Use a mix of two parts compost, one part coarse sand and one part perlite, and bury each seed about twice its own thickness deep. Water well, keep the pots outside in a cool, airy spot, and protect them from mice.
Plant out when the young tree is a hand tall and the stem has begun to stiffen, in full sun and on ground that drains freely. Space trees widely, because a mature stone pine is broad as well as tall. Water through the first two summers and then leave the tree to find its own way, since it tolerates drought far better than a wet root zone.
Feed lightly for the first seasons and then stop, as rich ground produces rank growth rather than the tight, flat crown. Let the lower branches remain while the tree is young; cutting them too early delays the parasol shape.
The pine processionary moth is the classic pest, its caterpillars marching in a nose-to-tail column and building white silk nests in the canopy; the hairs irritate skin and should never be handled. Shoot blight, caused by a Diplodia fungus, blackens young shoots in warm, wet weather, so prune out affected tips in dry conditions.
Our Take
If you are sowing for nuts rather than for timber, put this pine beside its fellow kernel-bearers. Swiss stone pine offers the same food in a colder climate, Korean pine is its east Asian counterpart, and single-leaf pinyon proves that a single needle can do the job.
Related Reading
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