Viper's Bugloss; Viper is from the genus name as above and Bugloss is from the Latin buglossus meaning Ox tongue referring to the rough to touch, oval leaves.
Other names:Blue Thistle (USA)
Summary:An erect, usually biennial herb with purple, trumpet shaped flowers with 4 protruding stamens and a large basal rosette of leaves.
Two. Oval. Hairy. Tip round. Sides rounded. Base tapered.
First leaves:Hairy. Oval. Tip pointed.
Leaves:Alternate. Forms a basal rosette that tends to wither as the plant matures and flowers.
Petiole - Short - none. 0-20 mm long.
Blade - Narrow lance shaped to oval, up to 200 mm long x 60 mm wide. Short stiff hairs. Tip round. Veins are longitudinal, not prominent and not branched.
Stem leaves - Alternate. Stalkless and elongated with a rounded base grading into narrow bracts on the flower head. Soft hairs.
Stems:Erect, 1 to many, freely branched, up to 1000 mm tall. Elongate in spring.
Hairy with broad bristle and short dense hairs. The flowering stem tends to be produced in the second season.
Flower head:Elongated, loose panicle of raceme like compact cymes with bracts or sometimes leafy. Flowers crowded along one side of a curved or initially coiled spike at the ends of stems or in axils.
Flowers:At ends of stems and in leaf axils on curved spikes.
Bracts - Longer than the sepals
Ovary - 4 celled, 4 lobed. Style hairy.
Sepals - 5, deeply lobed 5 mm long and up to 10 mm long when in fruit. Hairy.
Petals - 5 unequal lobes fused into a tube, initially pale blue and becoming bright blue, curved trumpet shaped, 15-30 mm long, usually less than 20 mm long.
Stamens - 5 of which 4 are longer and protrude from the flower.
Fruit:4 Nutlets, enclosed in the persistent swollen sepals.
Seeds:Warty, egg shaped, narrowed at the top. Hairless.
Roots:Strong, stout taproot with many laterals to 3 m deep.
Key Characters:Tubercle based and short hairs.
5 stamens of which 4 are longer and protrude from the flower.
Bright blue trumpet shaped flowers.
Biennial occasionally perennial or annual. Germinates autumn/winter. Flowers September-November and further flowering stems are produced in its second year. It is possible that in Tasmania this species survives as a perennial.
Flowering times:Late spring in NSW.
September to November in Tasmania.
Seed Biology and Germination:Vegetative Propagules:
Population Dynamics and Dispersal:
Origin and History:
Europe. Central Asia.
Introduced to Australia in 1820.
Distribution:ACT, NSW, NT, QLD, SA, TAS, VIC.
Found in a few isolated localities in the north-west and in the south of Tasmania.
Courtesy Australia's Virtual Herbarium.
Altitudes to 2100 metres.
Soil:Occurs on a wide range of soils.
Prefers light, well drained soils.
Used in herbal medicine for many things including an antidote for snake bite.
Detrimental:Weed of pasture, crops, disturbed areas, fallows, lucerne, roadsides and disturbed areas.
Potentially competitive in pasture and crops.
Toxicity:It contains pyrrolizidine alkaloids.
Horses, pigs and young or breeding stock should not be used for grazing Viper's Bugloss especially after spraying when it is more palatable. Potentially damaging levels of oxalates and nitrates may accumulate.
Legislation:Noxious weed of NSW, VIC and TAS.
Management and Control:Often establishes after overgrazing, cultivation or other disturbance and then prevents other more desirable species establishing.
Cultivation and herbicides provide good control in cropping situations.
Multiple cultivations are usually required to control late germinating seeds.
In pasture areas herbicides in combination with vigorous pasture species can reduce it to low levels.
Graze with sheep rather than cattle to prevent seed set. Rams or wethers are more effective than ewes.
Mowing can reduce seed set but usually requires an early mow at the bud stage and a late mow to control regrowth.
Spray grazing, early in the season gives very economical reductions in broad acre pasture infestations.
Isolated plants can be manually removed and burnt if flowering or seeding.
Graze heavily with rams or wethers over spring. Spray top at flowering and repeat if necessary. Burn stubble. Cultivate at or before the break of the season. Spray with knock down herbicides. Plant a crop using as much tillage as possible. Apply herbicides in crop. Burn stubble. Repeat for 3 years. Spray graze pastures annually before the weed has reached the 6 leaf stage and repeat if necessary for at least another 3 years and spray top or manually remove flowering plants. Shear sheep and allow up to 7 days for seed to pass through the gut of stock that have been exposed to weed seed before introducing them to clean areas.
For odd plants spray, until just wet, a 10 metre circle around the plant, with a mixture of 1 part of Tordon® 75-D in 100 parts of water. This will kill most broad leaf plants, but not grasses, and leave a residual herbicide in the soil that will control seedlings for about a year.
Herbicide resistance:Biological Control:
Bio control agents introduced to control Paterson's Curse will probably also affect Viper's Bugloss.
The Heliotrope moth (Utetheisa pulchelloides) is a white spotted moth and often seen in Heliotrope and Echium infestations. The caterpillars have sparse grey hairs, and are black with orange spots and broken cream lines along the body.
Related plants:Italian Bugloss Echium italicum) has 5 protruding stamens and is densely hairy.
Paterson's Curse (Echium plantagineum) has 2 protruding stamens and flowers several weeks earlier and is more protracted. Flowers are usually larger and not as blue. More palatable and more competitive. Leaves broader. Tubercle base hairs only. Stems tend to be longer and less branched.
Plants of similar appearance:The seedling and rosette is similar to that of Paterson's Curse (E. plantagineum), except that the leaves are less broad, and the veins are longitudinal and not branched. The stems branch more freely than those of E. lycopsis and are generally shorter. The stem leaves are sessile and elongated. The flowers are similar to those of Paterson's Curser (E. plantagineum) but slightly smaller and brighter blue in colour.
Similar plants include Amsinckia, Corn Gromwell, Paterson's curse, Heliotrope.
References:Auld, B.A. and Medd R.W. (1992). Weeds. An illustrated botanical guide to the weeds of Australia. (Inkata Press, Melbourne). P126-127. Photo.
Burbidge, N.T. and Gray, M. (1970). Flora of the Australian Capital Territory. (Australian National University Press, Canberra). P308-310.
Cunningham, G.M., Mulham, W.E., Milthorpe, P.L. and Leigh, J.H. (1992). Plants of Western New South Wales. (Inkata Press, Melbourne). P562.
Hyde-Wyatt, B.H. and Morris, D.I. (1980) The Noxious and Secondary Weeds of Tasmania. (Tasmanian Department of Agriculture, Hobart, Tasmania). P80-81. Diagram.
Lamp, C. and Collet, F. (1990). A Field Guide to Weeds in Australia. (Inkata Press, Melbourne).
Lazarides, M. and Hince, B. (1993). CSIRO handbook of economic plants of Australia. (CSIRO, Melbourne). #479.5.
Parsons, W.T. and Cuthbertson, E.G. (1992). Noxious weeds of Australia. (Inkata Press, Melbourne). P331-332. Photos.
Collated by HerbiGuide. Phone 08 98444064 or www.herbiguide.com.au for more information.