Pinus parviflora Seeds | Japanese White Pine
LATIN NAME: Pinus parviflora
COMMON NAME: Japanese White Pine
Plant Profile
In the old garden convention of Japan the two common pines are given sexes: the black pine is the male tree, vigorous and coarse, and the white pine is the female, slower and finer. It is the white pine that receives the most patient training, because it keeps its lower branches and grows slowly enough that a gardener can shape one tree over a working lifetime into a broad, flat cloud of foliage.
The cones are ovoid and small, between five and ten centimetres, carried in clusters of two or three on short stalks, with thick scales whose exposed ends are flattened. The specific epithet means small-flowered, a reference to those modest cones. Seeds are large for the size of the cone and carry only a short wing that detaches readily, so most of them fall close to the parent and are collected and buried by rodents and jays. Caches left unvisited are how the species colonises new ground.
White pine blister rust, a fungus that needs a currant or gooseberry bush as its alternate host, arrived in North America from Asia and killed five-needle pines across whole mountain ranges. Asian species had lived with it and carry resistance, and Japanese white pine has been used in crossing programmes with western white pine and sugar pine to bring that resistance into native populations.
Nursery plants are usually grafted onto Japanese black pine rootstock rather than grown on their own roots. Black pine tolerates heavier, wetter soil and grows faster, so a grafted white pine will sit in ground that the species would refuse. Inspect the union for suckers from the stock, which are green, two-needled shoots that will overrun the scion if left.
Training follows a calendar of small interventions. In early summer the new shoots, still soft, are broken or cut back by half to keep the growth dense. In autumn surplus needles are plucked from crowded branches so that light reaches the inner buds, and wired branches are adjusted after the wood has lignified. The same routine produces the bonsai sold around the world, and in the open garden it makes a low, wide specimen that takes wind and salt spray without scorching.
Science & Biotechnology
The kernel of a five-needle pine is a genuine nut, and its oil is unusual for the presence of pinolenic acid, a fatty acid with a double bond in an uncommon position that occurs in the seed oils of this group. That chemistry has drawn interest from nutrition research, and it is the same reason the seeds of the related Korean pine are eaten across northeast Asia.
Uses & Benefits
Pinus parviflora is small by pine standards, often eight to fifteen metres in the wild, and often much less in a garden, with a trunk that forks low and branches that spread almost horizontally. The bark is grey and smooth on young trees, breaking into plates with age, and the crown keeps the open, tiered silhouette that makes the species so useful as a garden subject.
Growing from Seed
The needles are arranged in bundles of five, between five and eight centimetres long, slightly twisted, and blue-green with conspicuous white bands of stomata on the inner faces; those bands give the foliage its frosted look from a distance. A bundle sits in a short sheath that soon falls away, and the needle tips are blunt rather than sharp to the touch. The bundle count alone separates the species from the two-needle pines of the same country, and it is the first thing to check on a doubtful plant.
Like all pines, the tree fills its resin ducts with a mixture of monoterpenes, chiefly alpha-pinene and beta-pinene with limonene and myrcene, together with diterpene resin acids that harden on exposure to air and seal a wound. The needle oil of the white pines has been used in chemosystematic work because its composition differs between species.
Mix three parts pumice or coarse grit, two parts composted pine bark and one part loamy topsoil, and firm it before sowing. Press the seeds one to two centimetres into the surface in autumn and leave the frame outside so the seed takes a cold, damp rest through the winter; water sparingly, because a pine seedling rots faster than it dries. Space seedlings in the frame at twenty-five centimetres.
White pines resent root disturbance, so the first move should be generous: wait until the seedling is about eight centimetres tall and has begun to make its first side shoots, then lift it with the whole root ball and set it directly in its final container or planting place. Water freely in the growing season and never let the roots stand in water; mulch with pine litter to keep the surface open and slightly acid. Young plants need shelter from drying wind in their first winter. Watch for the white pine aphid on new shoots, needle cast in humid weather, and scale insects on the older needles.
Our Take
A white pine grows at the speed of the person tending it, so start with a seedling you can shape and give it a place you will walk past every day. Anyone wanting a faster, bolder garden pine for the same conditions should read the training notes for Japanese black pine, the rootstock this species is usually grafted onto, and the work on Pinus thunbergii, which covers the same stock from the other direction. For a five-needle pine with pale peeling bark, see the lacebark pine notes.
Related Reading
Gardeners who grow Japanese White Pine often pair it with these related subjects: