(Echium plantagineum)

 

Paterson’s curse is a noxious, annual plant that usually germinates in early autumn and flowers in spring, but it can germinate at any time of year if conditions are favourable.

 

It readily germinates with unseasonal rains and can survive early and false breaks. For example, it can germinate with heavy summer rain and produce small plants that flower and set seed in autumn.

Seedlings quickly develop strong root systems and are quite drought resistant.

 

Each flower produces four rough, grey or brown wrinkled seeds. Three are shed, but one is usually retained in the bristly calyx, which readily attaches to a passing animal.

Seeds are also spread in grain and hay.

 

Flowering and seed production continues until November in most parts of the south-west but may continue into summer in well-watered sites.

Each plant can produce many seeds, which remain viable for up to six years. Dense stands eventually form a seed bank of up to 30 000 seeds/m².

 

Paterson’s curse is estimated to cost Australian sheep and cattle producers $250 million annually through lost productivity in pastures, control costs, and wool contamination.

It is highly competitive in pastures, replacing desirable plants without contributing to forage value.

Paterson’s curse contains pyrrolizidine alkaloids, which are toxic to livestock, particularly horses and pigs, though sheep can graze it for a time.

 

However, prolonged grazing of Paterson’s curse is harmful, even to sheep, because the alkaloids eventually cause liver damage, especially if stock consume large amounts of this weed in winter and spring and then graze on common heliotrope over summer.

 

Paterson’s Curse is on the move in some areas of the South West.

Please let us know when you see it so that we can map the extent of the problem or report on WeedWatcher or  MyPestGuideReporter apps.

 

Note for management calendar: a faded icon means occasionally.