The species of Taxus are more geographically than morphologically separable; and they were all treated by Pilger (1903) as subspecies of Taxus baccata. All species are poisonous; most contain the anti-cancer agent taxol; and a study of heartwood constituents of Taxus baccata, Taxus brevifolia, Taxus cuspidata and Taxus floridana found them to be chemically almost identical. However, the vast ecological amplitude displayed by the various described species (over 60° of latitude and an impressive temperature and precipitation range) suggests that they are, in a meaningful sense, true species. Detailed study of the genus (not neglecting the cultivated representatives), including extensive fieldwork, is much needed and long overdue[].

Common Name: Japanese Yew

General Information

Taxus cuspidata is an evergreen, spreading shrub or a low tree with a pyramidal crown; it can grow up to 18 metres tall[, ]. The bole often branches from low down - usually up to 100 - 150cm in diameter, in very old trees it has been measured up to 280cm in diameter[, ].
The plant is harvested from the wild for local use as a food, medicine and source of materials. It is harvested from the wild on a commercial basis as a source of the anticancer drug 'taxol'. Often grown as an ornamental in gardens, where it can be used as a hedge, there are many named cultivars.
Exploitation of this species has only affected subpopulations in certain parts of its extensive range, hence it is assumed that population reduction has been limited. The plant is classified as 'Least Concern' in the IUCN Red List of Threatened Species(2013)[].
Commonly grown as an ornamental, the plant has escaped from cultivation in parts of northeastern USA and is reported to be invasive in New Jersey and Virginia

Known Hazards

All parts of the plant, except the flesh of the fruit (actually an aril), are potentially highly poisonous. They contain the alkaloid taxine and , if ingested, can cause nervousness, trembling, slow pulse, pupil dilation, difficult breathing, abdominal pain, vomiting, diarrhoea, weakness and convulsions - in larger doses it can be fatal, having a paralyzing affect on the heart[, , , , , , ].

Botanical References

, ,

Range

E. Asia - Russian Far East, northern China, Japan, Korea

Habitat

Occasional in mixed conifer and conifer-deciduous forests in lowland to lower montane regions; at elevations from 100 - 1,600 metres[]. The var nana is found mainly on rocky sea coasts, sometimes also on exposed rock outcrops in the interior[].

Properties

Weed Potential	Yes
Conservation Status	Least Concern
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Evergreen Tree
Height	10.00 m
Growth Rate	Slow
Pollinators	Wind
Self-fertile	No
Cultivation Status	Ornamental, Wild

Cultivation Details

When dormant, Taxus cuspidata is very cold hardy, tolerating temperatures down to about -35°c[] or between -23.2°c and -17.8°c[]. However, it requires more summer heat and humidity than the related Taxus baccata in order to fully ripen its wood. In cool and maritime climates it is often no more than a shrub[]. Young shoots can be damaged by late spring frosts. The foliage may turn reddish-brown in cold winters[].
Plants are very shade tolerant[], though they also succeed in full sun. They thrive in almost any soil, acid or alkaline, as long as it is well-drained[, ]. Succeeds in dry soils[]. The plant grows in the wild on a variety of soils derived from granitic, schistose or serpentine base rocks[]. In China it grows in acid soils in cold, humid places[]. Plants grow best in a position sheltered from cold, dry winds[].
This species is said to be the hardiest, fastest-growing and easiest to cultivate of all yews[].
Plants are tolerant of urban pollution[].
There are several named varieties selected for their ornamental value[].
Plants produce very little fibrous root and should be planted in their final positions when still small[].
Plants in this genus are notably resistant to honey fungus[].
A dioecious species, both male and female forms must be grown if fruit and seed are required. Female plants fruit freely in Britain if they are pollinated[, ].

In horticulture it has been so popular for a long time that the species is now rare in the wild, but it is grown nearly everywhere in the urbanized areas of Japan. Numerous cultivars exist, and the species is used in bonsai culture. Japanese yew was introduced to Europe (England) in 1855 by Robert Fortune and more cultivars have been developed here as well as in the USA. A hybrid between T. Baccata and T. Cuspidata (Taxus ×media Rehd.) originated in the USA around 1900 and has given rise to further cultivars[].

Edible Uses

Fruit - raw or made into jam[, ]. Very sweet and gelatinous, most people find it delicious though some find it sickly. The fruit is a fleshy berry about 8mm in diameter and containing a single seed[]. All other parts of this plant, including the seed, are highly poisonous. When eating the fruit you should spit out the large seed found in the fruit's centre. Should you swallow the whole seed it will just pass straight through you without harm, if the seed has been bitten into, however, it could cause some problems.

Medicinal

Modern research has shown that yew trees contain the substance 'taxol' in their shoots and bark. Taxol has shown exciting potential as an anti-cancer drug, particularly in the treatment of ovarian cancers[, ]. This remedy is very toxic and, even when used externally, should only be used under the supervision of a qualified practitioner[]. See also the notes above on toxicity.
A compound used to treat diabetes is extracted from the wood, bark, leaves, and roots[].

The plant has been used as an abortifacient and antidiabetic[, ].

Agroforestry Uses:

The tree responds well to trimming and can be grown as a hedge[]. It is used in topiary[].

Other Uses

The bark contains around 10% tannins[].
A brown dye is obtained from the heartwood[, ]. Red according to another report[].

The seeds contain around 29% fats[]. An oil is extracted from the seeds[]. The seeds contain oils which are extracted, but treatment is required to neutralize the poisonous alkaloids[].

The wood is fine-grained, hard, strong, elastic. It takes a beautiful polish. The wood is used for interior finish, furniture manufacture, utensils, marquetry, cooperage, bath tubs, chopsticks, pencils, clogs, making bows, building construction, and as a carving and turning material[, , , , ].

Propagation

Seed - can be very slow to germinate, often taking 2 or more years[, ]. It is best sown as soon as it is ripe in the autumn when it should germinate 18 months later. Stored seed may take 2 years or more to germinate. 4 months warm followed by 4 months cold stratification may help reduce the germination time[]. Harvesting the seed 'green' (when fully developed but before it has dried on the plant) and then sowing it immediately has not been found to reduce the germination time because the inhibiting factors develop too early[]. Prick out the seedlings into individual pots once they are large enough to handle and grow them on in pots in a cold frame. The seedlings are very slow-growing and will probably require at least 2 years of pot cultivation before being large enough to plant out. Any planting out is best done in late spring or early summer, after the last expected frosts[].
Cuttings of half-ripe terminal shoots, 5 - 8cm long, July/August in a shaded frame. Should root by late September but leave them in the frame over winter and plant out in late spring[]. High percentage[].
Cuttings of ripe terminal shoots, taken in winter after a hard frost, in a shaded frame[].
Layering