Common Name: Metake

General Information

Pseudosasa japonica is an evergreen bamboo that usually grows 1 - 3 metres tall, occasionally to 5 metres; the erect, woody culms are around 15mm in diameter with thin-walled internodes. The rhizomes are elongated, the plant having a running habit that can produce new canes some distance from the main clump, especially in warm climates. This tendency to run, however, is somewhat curtailed in cooler climates, where new shoot production can be rather reduced.
The plant is harvested from the wild for local use as a food, medicine and source of materials. A very ornamental plant, it is often grown as a hedge or screen in gardens[].
The rootstock is running, capable of spreading 150cm in every direction every year. It can escape from cultivation, when it can become very invasive[]. It is considered an invasive species in several N. American states. It is fairly easy to controli n the garden, however, by mowing around the clump and, if any new shoots that are not wanted are broken off whilst they are still small and brittle. It is important, however, to destroy any unwanted parts of the root that are dug up otherwise they can regrow and form new plants.

Known Hazards

None known

Botanical References

, ,

Range

E. Asia - central and southern Japan, south Korea

Habitat

Woodland and damp places, forming thickets in open country[].

Properties

Weed Potential	Yes
Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Evergreen Bamboo
Height	4.50 m
Pollinators	Wind
Cultivation Status	Wild

Cultivation Details

Pseudosasa japonica is one of the easiest bamboos to grow in the temperate zone[] It is very hardy, tolerating temperatures down to at least -15°c[, ], with some reports saying -24°c.
Prefers an open loam of fair quality and a position sheltered from cold drying winds[, , ] but it tolerates maritime exposure[, ]. Succeeds on peaty soils[]. Succeeds in soils that are half earth and half stone[]. Requires abundant moisture and plenty of organic matter in the soil[]. Endures near-saturated soil conditions[]. Dislikes drought[].
New shoots appear from mid spring[].
This species is notably resistant to honey fungus[].
Bamboos have an interesting method of growth. Each plant produces a number of new stems annually - these stems grow to their maximum height in their first year of growth, subsequent growth in the stem being limited to the production of new side branches and leaves.
Bamboos in general are usually monocarpic, living for many years before flowering, then flowering and seeding profusely for a period of 1 - 3 years before usually dying. This pattern can vary - sometimes flowering is sporadic, with plants flowering annually and not dying; at other times it is gregarious with all the plants in a specific species coming into flower at the same time.
This species often flowers lightly for a number of years without dying out though it seldom produces viable seed[]. Occasionally the plants can produce an abundance of flowers and this severely weakens, though does not usually kill, the plants. They can take some years to recover. If fed with artificial NPK fertilizers at this time the plants are more likely to die[]. Many plants flowered heavily in the late 1980's and are only slowly recovering.

Edible Uses

Young shoots - cooked[, , ]. Harvested in the late spring when about 8 - 10cm above ground level, cutting the stems 5cm or more below soil level. They have a rather bitter flavour[].

Seed - used as a cereal[]. Small quantities of seed are produced in many years but it is seldom viable.

Medicinal

The leaves are anthelmintic, antivinous, stimulant, tonic[]. A wash is used in the treatment of favus of children and other eruptions[].

The root is cooling and is used in the treatment of fevers[].

The bark is used in decoction for the cure of hemorrhage from the bladder[].

The sap is used in the treatment of ulcerated sore mouth, ophthalmia, and toothache[].

Agroforestry Uses:

Plants can be grown along the river edge to protect the banks from erosion[].
Tolerant of maritime exposure, it can be grown as a screen or windbreak hedge in very exposed positions[, ]. The culms make an excellent wind filter, slowing its speed without creating turbulence. The leaves may look somewhat tattered by the end of the winter but plants will soon produce new leaves[]. The hedge is also very effective in reducing noise, such as that of road traffic.

Other Uses

Canes are fairly thin walled but make very good plant supports[, , ]. Smaller canes can be plaited together and used as screens or as lathes for walls and ceilings[].

Propagation

Seed - if possible, surface sow the seed as soon as it is ripe in a greenhouse at about 20°c. Stored seed is best sown as soon as it is obtained. Do not allow the compost to dry out. Germination usually takes place fairly quickly so long as the seed is of good quality, though it can take 3 - 6 months. Prick out the seedlings when they are large enough to handle and grow them on in a lightly shaded place in the greenhouse until they are large enough to plant out, which might take a few years. Plants only flower at intervals of several years and so seed is rarely available.
Division in late spring as new growth commences. Very easy, single canes of the current years growth can be used. Pot them up in light shade in a greenhouse. Make sure the foliage is not allowed to dry out - misting 2 - 3 times a day for the first couple of weeks following division can be very helpful. Plant out in the summer once they are growing away strongly.
Cane layering in May. Detach individual canes and lay them horizontally in trenches 15cm deep. New shoots should arise from each joint.
Rhizome cuttings.