Picrasma quassioides Seeds | Quassia Root Slice
LATIN NAME: Picrasma quassioides
COMMON NAME: Quassia
Plant Profile
Picrasma quassioides forms an open, round-headed small tree around ten metres tall, with pinnate leaves whose glossy oval leaflets turn brilliant red in autumn, one of the reasons Japanese gardens value it. Small greenish flowers open in loose panicles through the warm season and are followed by small round drupes that shade from red to black. The bark of trunk and branches, and the wood beneath it, carry the bitter load that made the tree famous.
For the ornamental grower the surprise is the autumn display, when the leaflets flare scarlet and crimson across the whole crown. Combined with tidy proportions and tolerance of part shade, this makes the species a genuine garden tree in temperate to warm-temperate regions, not merely a medicinal curiosity.
Historically, quassia chips bittered digestive tonics, substitute bitters and liqueurs, and brewers once used the extract as a hop extender and as a foam-stabilising addition in ale. The wood also entered old household practice as a rinse against head lice. The taste is unpalatably intense in quantity, so every traditional preparation works at dilution, and anyone using quassia internally today should treat it strictly as a professional’s material.
Science & Biotechnology
The quassinoids, led by quassin and neoquassin, are degraded triterpene lactones of remarkable bitterness. The bark also carries beta-carboline alkaloids, including 1-vinyl-4,8-dimethoxy-beta-carboline, and research groups have examined the extracts for antimicrobial and anti-ulcer activity. Bitterness itself has a physiological logic: intensely bitter preparations stimulate digestion through taste receptors, which is precisely why bitters found their way into tonic bottles.
Quassia extract is a classic botanical insecticide with an unusually gentle profile toward beneficial insects and vertebrates. A standard garden preparation soaks wood chips or bark in cold water for a day, and the strained liquid is sprayed against aphids, sawfly larvae and leafhoppers. Because the compounds act on contact and by ingestion with low residual persistence, the spray suited organic practice long before the word organic was fashionable.
Current work follows two lines: standardising extracts so that quassinoid content is consistent chip to chip, and tissue-culture studies that might lock in high-yielding clones. Neither has displaced the simple old method of steeping shavings, which is part of the species’ charm.
Uses & Benefits
Two different trees share the quassia name. The South American Quassia amara is a small shrub with brilliant red flowers; the Asian Picrasma is a temperate tree with insignificant green blooms. Both are sold as quassia chips, and both owe their bitterness to quassinoid compounds, but a buyer who knows the difference reads the chips: Asian material shows bark rings on thicker, woody pieces, while Surinam quassia comes as thinner, paler shavings.
Growing from Seed
The tree asks for the conditions of its native forest margins: deep, rich, moisture-retentive soil, shelter from harsh wind and space for a clean trunk.
The drupes must have their pulp removed before sowing, since the flesh hinders sprouting. Clean seed goes into a moist, humus-rich seedbed under light shade, and emergence is drawn out and uneven, so patience and a marked pot are part of the job. Move seedlings on once they carry several true leaves and stand clearly above ten centimetres.
Train a single clear stem by removing low side shoots while they are thin, and let the crown spread. Feed with compost each spring and mulch to hold summer moisture. Pests rarely trouble the tree; the same bitterness that flavours sprays protects the foliage. Established trees tolerate ordinary winters in warm-temperate districts but appreciate shelter at the cold end of their range.
Propagation does not stop at seed. Semi-ripe cuttings taken in summer root under mist or a plastic cover with bottom warmth, and older trees can be layered by pegging a low branch into the soil until it roots. Both routes preserve the bitterness of a known parent, which matters because quassinoid levels vary considerably from tree to tree even within a single stand.
Our Take
If bitterness is your interest, quassia has famous company: the root of yellow gentian carries a bitterness of equal intensity, the foliage of wormwood built an entire drinking culture, and the bark of barberry adds its own alkaloid bite to the old pharmacy shelf. A garden row of these four plants would give a distiller, a brewer and an organic farmer work for years.
Related Reading
More species in the same orbit as Quassia: