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| Paterson's Curse (Echium plantagineum L.) and Viper's Bugloss (Echium vulgare L.) Control GuideRevised 11/02
Echium spp 1997.pdf | |
Paterson's Curse is an erect, annual plant, generally 600 to 900 mm tall at maturity. Seedling plants develop into a rosette with stalked, slightly hairy leaves, up to 300 mm long with distinct lateral veins. Leaves on the flowering stem are narrower and smaller, without stalks and almost stem clasping. The plants are occasionally single-stemmed but usually several much branched stems with stout hairs or bristles arise from the base. The flower head is curled and unrolls as the flowers open. Flowers are 20-30 mm long, trumpet shaped and usually blue/purple, but may be pink or white. Each flower has five petals and produces four rough, brown or grey crinkled seeds surrounded by a husk which is covered with stiff bristles.
The seedling and rosette of viper’s bugloss are similar to the above except that the leaves are narrower and the veins are longitudinal and unbranched. The stems branch more freely than those of Paterson’s curse and are generally shorter. The flowers are similar to Paterson’s curse but slightly smaller and generally darker blue in colour. Viper’s bugloss is usually a biennial or sometimes perennial and it flowers several weeks later than Paterson’s curse with flowering extending over a longer period.
Both species are native to the Mediterranean region and western Europe and have been found in all States of Australia, except that viper’s bugloss is not found in Queensland. Paterson’s Curse was first recorded in Tasmania in 1869 and was probably originally imported as an ornamental species. Viper’s Bugloss was first recorded in Tasmania in 1912.
Paterson’s Curse occurs in all agricultural areas of Tasmania in small scattered infestations. It is most common near old homesteads or the sites of old homesteads, housing blocks in suburbs, or in rural areas where poultry are kept, and along roadsides. Infestations occurring in the State may have arisen from contaminated feed grains imported from interstate.
Viper’s Bugloss is less common in Tasmania being generally restricted to dry banks in the south of the State.
Plants of Paterson’s Curse can be found at any time of the year in all stages of growth. Mostly however the seeds germinate after the first autumn rains and develop into large flat rosettes during the winter months. Several germinations are likely during the autumn. In late winter, stems are produced, flowers develop in the spring and seeding commences in early spring and continues to mid summer when the plants die. Any disturbance at this stage however, such as mowing or grazing, is likely to encourage the production of new stems or tillers which will eventually produce seed. Some plants damaged by grazing or mowing may not flower in the first year but survive and flower in the second year. Viper’s Bugloss may flower in both the first and second season of growth. It may even persist for several years as a short lived perennial, flowering annually.
Both species are spread by seed only. Seed may be spread after ingestion by grazing animals or by birds or in the coats of animals; seed also is spread by water or earthmoving equipment, particularly along roadsides. Seeds are not spread by wind.
Seed of Paterson’s Curse may remain dormant in the soil for up to six years although most will germinate within two years of maturation under favourable conditions. Seed germination is favoured by moderate to high temperatures and Paterson’s Curse may germinate earlier in the late summer/autumn than most other winter annual species. Its reportedly high drought resistance enables it to survive after a false autumn break and to gain a competitive advantage over late germinating species. Conversely if there is a late autumn break, germination of Paterson’s Curse is slow under the cooler conditions and seedling establishment is reduced.
In Australia, opinions differ on the weed status of Paterson’s Curse in pasture. Some reports suggest that it is a weed because it competes strongly with more valuable pasture plants and then dries off in spring leaving little residue for the critical summer-autumn period. Others suggest that the high productivity of Paterson’s curse makes it a useful forage species. The young growth is readily eaten by stock, especially sheep, and is as nutritious as recognised pasture species, whilst the older growth is rough and hairy and generally avoided by stock.
However, the herbage of Paterson’s Curse contains pyrrolizidine alkaloids which may cause chronic liver damage and animal mortality, especially if substantial amounts of herbage are eaten over prolonged periods. However, in practice, stock deaths because of plant toxicity are rare and may be avoided with good pasture and livestock management. Sheep, goats and cattle are least susceptible with horses and pigs being most at risk.
Paterson’s Curse is rarely a weed of crops as it germinates early in the autumn and seedlings are usually killed by normal pre-sowing cultivations or herbicide applications.
Viper’s Bugloss is less palatable to stock than Paterson’s Curse and is less competitive with desirable pasture species. It also contains pyrrolizidine alkaloids and is potentially toxic to livestock.
Paterson’s Curse and Viper’s Bugloss are both declared weeds in Tasmania, largely due to actual and potential impacts on agricultural productivity. As such, importation, sale and distribution of these plants are prohibited. The legal responsibilities of landholders and other stakeholders for these declared weeds are specified in statutory weed management plans (Paterson's Curse, Viper's Bugloss) available from the Department.
Hand hoeing, pulling, and cutting are methods suitable for isolated plants provided the growing point and the top 20 to 40mm of the tap root are removed, otherwise regrowth may occur. Flowering plants should be burned or otherwise destroyed because seed may continue to mature on a plant even after it is cut, pulled, or hoed.
Heavy grazing is an effective means of controlling Paterson’s curse. It should be concentrated when plants are young, continued at regular intervals during the year and again concentrated at the end of the year when plants are flowering. Plants that escape grazing should be handpulled or cut to prevent seeding. Sheep are the most effective grazing animals to use. Grazing should be carefully managed given the potential for Paterson’s curse to cause liver damage. Viper’s bugloss being less palatable is not so effectively controlled by grazing.
Both species can effectively be controlled in arable areas by cultivation, especially if followed by cropping with either root or cereal crops, or establishment of a vigorous smothering pasture.
CSIRO has conducted extensive research on biological control of Paterson’s curse in Australia since the mid-1980s. This has resulted in the selection of several agents that have the potential to establish in the field. One agent has been released in the State, Dialectica scarlariella but has failed to establish field populations. Other agents are available from the mainland and will be considered for release in Tasmania in the future.
The success of these agents is dependent on an integrated program of weed management being used to complement the biological control measures. Biological control is particularly suited to large extensive infestations of Paterson’s curse.
Paterson’s Curse and Viper’s Bugloss at the seedling stage are susceptible to growth regulator type herbicides applied either as spot or boom sprays. For satisfactory control of both weeds, they must be sprayed when young.
In years when there is an early autumn break and large numbers of Paterson’s Curse germinate before the temperature falls, autumn spraying can be very effective. Spraying at this time also requires lower herbicide rates, is less damaging to clover and allows the desirable pasture species to grow with reduced competition.
The use of a wiper applicator if the Paterson’s Curse population is reasonably uniform in size can overcome most of the problems arising from damaging desirable pasture legumes if the area was boomsprayed.
For effective chemical control the plants must be growing actively. Plants subject to stress due to waterlogging, drought or low temperatures are far less susceptible to herbicides.
Boom Spraying
The use of 2,4-D based products on new pasture is not recommended. Registered MCPA based products may be more suitable. 2,4-D (amine and ester) and 2,4-DB products can be used on established pasture; use should be on young Paterson’s Curse plants (up to 6 leaf stage). Unless clovers and other legumes are well protected by grass, clovers and other legumes are likely to be damaged.
Spot Spraying
2, 4 -D (amine and ester) products can be used as spot sprays in pasture. Other products registered for spot spraying of Paterson’s Curse are clopyrralid and glyphosate. Although clopyralid does not damage grasses, glyphosate is a non-selective herbicide, and will damage or kill grass species.
Wiper Application
The application of a herbicide such as glyphosate using a wiping system is a suitable alternative where clover or legume damage needs to be avoided or where a pasture is newly established. Because the herbicide is applied selectively directly to the weed, not overall to the pasture, no clover damage results. The quantity of chemical used is also far less than with other application methods. Before employing this method of application check the label to ensure the herbicide is registered for wiper application.
Non-crop, Roadsides and Waste Areas
In these situations there is a wider range of registered herbicides including sulfmeturon, metsulfuron-methyl, glufosinate ammonium, and glyphosate products.
Spot or boom sprays can be used in these situations as recommended for established pasture.
For total vegetation control such as along fence line or roadsides products such as glyphosate or sulfmeturon could be used.
Growth regulator herbicides such as 2,4-D, can cause severe damage to a wide range of vegetable and horticultural crops. Great care must be taken to prevent spray or vapour drift reaching crops such as grape vines, tomatoes, vegetables, poppies or flower crops.
Grape vines in particular are highly sensitive to 2,4-D. The application of 2,4-D is restricted to the period between 15 April and 15 September. To use 2,4-D outside this time period a permit is required from the Registrar of Chemical Products, DPIW.
| Some herbicides are toxic to bees.
As a general rule, avoid applying herbicides when and where bees are foraging.
Always read the label. |
Note:
These herbicide recommendations are made subject to the product being registered for that purpose under relevant legislation. It is the user's responsibility to check that registration or an off-label permit covers the proposed use. If in doubt, check with the Registrar of Chemical Products, Department of Primary Industries and Water. Statewide Freecall 1300 368 550.
Paterson's Curse
Chemical Control Recommendation
Boom Spray Application
Situation | Growth Stage | Herbicide | Commercial product
Example
(Content of active ingredient) | With holding Period (days) | Application Rate of Commercial Product per hectare | New Pasture | seedling | MCPA/ diflufenican+ | Tigrex
(250/25 g/L) | 7 days | 750 ml | Established Pasture | seedling to rosette | 2,4-D amine# | (500 g/L formulations) | 7 days | 2.1 to 2.8 L | | | 2,4-DB* | Legumex ® ( 400 g/L) | 7 days | 2.8 to 3.5 L | | shooting plants | 2,4-D ester# | Low Volatile Ester 400 Herbicide®(400 g/L ) | 7 days | 1.4 to 2.8 L | Non-crop, Roadsides and Waste areas | rosette to early flowering | metsulfuron-methyl## | Brush-Off Brush Controller®
(600 g/L) | nil | 15g/ha | | Young seedlings | 2, 4-DB* | Buticide®
(400 g/L) | 7 days | 2.8 L | | seedling to rosette (max 5cm diam) | bromoxynil | Buctril 200®
(200 g/L) | 14 days | 2 L | | seedlings to shooting plants | glyphosate | (360 g/L formunlations) | 1 day | 2 to 3 L |
+ Suppression only.
# Use of these products may result in damage to clovers and other legume species unless well protected by grass.
* Use when clover has 1 to eight trifoliate leaves. Do not use on berseem clover.
## May not be able to establish clover or other pasture legumes on treated areas for up to 12 months after application.
Spot Spraying
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