teasel(redirected from D japonicus)
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(Dipsacus), a genus of herbaceous plants of the family Dipsacaceae. They are biennial, less frequently perennial, grasses with prickly stems 0.5-2.0 m high. The stem leaves are opposite, often in connate pairs at the base. The flowers are small, gathered in globose racemes that may be elongated or spherical. The genus comprises 15-20 species growing in Europe (mainly the Mediterranean countries), South and East Asia, and Africa. In the USSR there are six species, in the southern European part, the Caucasus, and Middle Asia, rarely (one species) in Western Siberia.
Fuller’s teasel (D. sativus or D. fullonum) has practical significance. A biennial that in the first year forms a thickened root and a rosette of dark green elongated leaves up to 25 cm long, and, in the subsequent year, a stem 0.8-1.5 m long, fuller’s teasel has racemes at its apex and lateral branches of friezing cones 7-11 cm long. When they ripen they form a seed ball with sharp, stiff bracts of scaly hooks that are curved downward. These friezing cones are used in the textile industry as cards for teasing fabric (combing the nap). The plant has been cultivated since ancient times. In the USSR it is grown in the Crimea, the Caucasus, and Middle Asia. The yield of cones is 6-7 centners per hectare.
Teasel is planted in the plowed area of crop rotation. It is sown in the spring with interrow intervals of 60-70 m at a depth of 3-5 cm; the sowing norm is 5-7 kg/hectare. In the first year the plantings are harrowed before the sprouts ap-pear, hoed four or five times, thinned to a distance of 15, and then 30, cm, and hilled in the winter. In the second year more plants are planted in the thinned places, hoeing is done two to four times, and the plants are shaped—that is, six to eight cones are left on each plant and the apical and small cones are removed. Teasel is gathered when it is technically mature, in three or four operations, cutting the cones with a pruner (with stem knife of 20-25 cm); then the cones are dried, the leaves at the base and the pappi at the top are removed, and the cones are sorted and packed in boxes.
REFERENCEOrlov, V. T. Vozdelyvanie vorsianki. Moscow, 1950.
M. E. KIRPICHNIKOV and V. T. ORLOV