Friday, March 6, 2009

Wild Teasel

Wild Teasel (Dispacus fullonum) This noxious weed is not that common in South Gippsland the only sighting I have seen is in the Dumbalk area mainly on roadsides. It has the potential to invade pastures. It is an erect biennial herb to 2m high, reproducing by seed. Its stems and leaves are covered in prickles not unlike thistle. Has a very attractive purple or lilac flower in a cylindrical form. Seedlings emerge after autumn rains, or at other times following soil disturbance if moisture is adequate, and develop in to large rosettes by spring. Flowering stems are not produced until the second or even later years, the size of the plant has to be big enough. In each head, flowers open first in a ring around the middle of the head and as subsequent flowers open the ring moves up and down the head. Plants die in autumn and the dead stems remain standing for many months or even years. The Australian woollen industry imported teasel heads from England for many years, in the 1930’s was paying 15 shillings per 100 heads. The heads with its hooked floral bracts were used in the textile industry for carding and teasing wool and to raise the nap on woollen fabrics. The heads were either bound together into brushes and used by hand or were set into frames on a machine. Wild teasel can be grubbed out taking care to remove the tap root. It can be controlled with a selective herbicide.