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.

Inaction on thistles costs money

Spear Thistle Cirsium vulgare. A large spear thistle rosette covers about one-third of a square metre, and because it is not readily grazed by stock, the carrying capacity of paddocks with dense patches of thistle is reduced considerably. In a survey carried out in a New Zealand study where for every additional thistle per square metre in pasture there was a decrease of 1.68 kg in the live weight gain of sheep. In addition to direct competition, the spiny nature of the thistle also deters animals from grazing pasture in the vicinity and patches may become so dense that that are impenetrable to stock. Another disadvantage is that contaminated hay is downgraded in quality and price. Sheep grazing encourages spear thistle by reducing competition from neighbouring plants. This is reflected in increased thistle growth, flowering and seed production on heavily grazed pastures. In contrast, thistles are usually sparse on ungrazed sites. This weed readily establishes in high fertile soils which is bare of vegetation at the end of summer. Local landholders recently have expressed great concern about the amount of thistles on some neighbouring properties, landholders are reminded that it is an offence under the CALP act not to control and eliminate this weed. Isolated patches can be grubbed out but most of the root system should be removed. Target the rosette stage with a selective herbicide; ensure there is competition from other plants that can replace the weed. Follow up your work and be persistent in implementing a long term management plan.

Controlling Ragwort

Driving around South Gippsland one can see many ragwort infestations large and small along roadsides and properties. It is most important that these plants are prevented from seeding setting another 10 years worth of infestation in to the district.

Blackberry and ragwort are the responsibility of adjacent landholders on all shire roadsides and on private land owners are expected to prevent the growth and spread to neighbours. The complaints about neighbours has started to escalate over the last few weeks. Once ragwort has flowered you do not have long left before it goes to seed. It can be foliar sprayed with herbicide at the flowering stage but once the flower heads start to brown it is better to cut of the heads put in a black plastic bag and leave in the sun to solarise and then spray the rest of the plant. If slashed or pulled ragwort will still seed and grow from root fragments. It is possible to use aerial application on steep hard to get to areas. Experience has demonstrated that tackling the ragwort problem occasionally or intermittently will not achieve long term control. Ragwort’s capacity to reinfest requires control programs to be well planned and sustained over a number of years. Landholders undertaking a high level of on-going control can expect excellent results.

In recent years considerable work has been put into the formation of Ragwort Control Groups and Landcare Groups enabling landholders to work together to help each other clean up their respective properties. It is up to the whole community to work together to keep this noxious weed under control, not to do so will result in loss of productive land and increased disputes between landholders.