Lithocarpus pachylepis Seeds | Thick-scaled Tanoak
LATIN NAME: Lithocarpus pachylepis
COMMON NAME: Thick-scaled Tanoak
Plant Profile
Thick-scaled tanoak is an evergreen tree of the beech family, recorded from southern China and northern Vietnam, where it grows in mixed hill forest on acid soils. A mature specimen reaches ten to fifteen metres with a broad, rounded crown of leathery, obovate leaves that stay deep green all year. The name refers to the acorn cup, which is covered in thick, appressed scales that give it a heavy, armoured look, quite unlike the shallow saucers of the oaks beside it. Nuts sit in these cups through a second autumn, turning from green to a dull brown. Bark is grey and roughly fissured, and the timber is hard, dense and slow to rot.
Science & Biotechnology
Lithocarpus is the second-largest genus in Fagaceae and the one botanists use to test ideas about how oaks and stone oaks diverged. The genus keeps male and female flowers in separate catkins on the same tree, and its acorns sit upright rather than hanging, a small difference with a long evolutionary history behind it. Lithocarpus pachylepis belongs to the group with thick, spirally arranged cup scales, and its leaf anatomy, with a thick cuticle and sunken stomata, fits a tree that has to keep working through a dry, cool season. Seed studies in the genus show recalcitrant acorns: they die if dried below about thirty per cent moisture, so storage means damp, cool conditions and a short window. Wood anatomy and carbon storage in these forests have also drawn attention, since stone oak stands hold more biomass per hectare than the pine plantations that replace them.
Uses & Benefits
The nuts are edible once the tannins are leached, and rural households in the tree’s range have boiled and soaked them for flour and for a coarse porridge. It is not a commercial crop, and nobody should plant it expecting an orchard. The wood is another matter: hard, fine-grained and resistant to rot, it goes into tool handles, posts and the frames of farm buildings. In the garden the tree works as a structural evergreen for a large plot, giving a dense screen and a dark foil for lighter planting. Its acorns feed jays, squirrels and rodents, and the insects living in its bark and leaf litter are the base of a small food web. For a landowner on acid soil in a mild climate, it is a tree that holds a slope and asks nothing after the third year.
Growing from Seed
Collect acorns as soon as they fall and do not let them dry. Float them in water, discard those that swim, and sow the rest in a deep pot of leaf mould, grit and garden soil within a week of gathering. Bury each nut on its side at twice its own depth. Keep the pots outdoors in a cold frame; germination is slow and uneven, often spread over two springs, and the radicle appears before the shoot. Mice are the main danger, so cover the pots with mesh. Seedlings transplant badly once the taproot has run, so give each one its own container from the start and plant out at the second winter, in a spot that gets sun for half the day and never holds water.
Our Take
A stone oak for people who plan in decades. It is slow, tough, and the acorns are worth the wait.
Related Reading
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