Scientific Name: Echium plantagineum L. (= E. lycopsis L.)

Family: Boraginaceae

Common names: Patterson’s curse, salvation Jane, Pers-Echium (Afr), Purple viper’s bugloss, Franklin weed

Bees love it. Horses and cattle get sick if they eat it and may even die. Commonly referred to as Paterson’s or Patterson’s curse (Echium plantagineum), this lilac-flowering invasive weed is flourishing across the Western Cape. Not many people are aware that it is an invasive weed, and because of its beautiful purple flower they think it is harmless.

Patterson’s Curse which was introduced to South Africa as an ornamental species has become a significant threat not only to the natural diversity but also to cultivated crops and pasture species of the area by out-competing them for space, water and sunlight. A dense population of echium can produce a seed bank of up to 30,000 seeds per square meter.

Distribution:

Paterson’s Curse comes from the Mediterranean region of Europe and is a well-publicised agricultural weed in Australia. It is thought to have arrived in Cape Town during a pit-stop of a vessel from the UK destined for Australia during the late 1700s. These vessels often carried livestock and feed which may have been contaminated with Paterson’s curse seeds. It comes to dominate pastures and rangelands, and substantially reduces the production of livestock in these invaded areas

Description:

It is a deep-rooted biennial that can grow up to 1m high. The leaves and stems are covered with coarse, white hairs. The stem leaves are long and small and the basal rosette leaves are broad and large with prominent lateral veins. Blue or purple flowers appear from spring to autumn.

Conservation status:

As a declared weed, Paterson’s Curse is listed as a Category 1b invasive plant on the National List of Invasive Species. This means that property owners and organs of state have a duty of care to control and remove it from their land.

Salsola sp.

Family: Amaranthaceae

Common names: Russian thistle, rolypoly, saltwort, windwitch, tumbleweed, common saltwort, and prickly glasswort, kakiebos, taaibos, tolbos.

Tumbleweed is an annual weed that begins life as a typical multiple branched bush, which then takes on a spherical form. It depletes soil moisture and interferes with cultivation operations. This species invades roadsides, disturbed sites, riverbanks, riverbeds, in dry or somewhat saline areas.

Description

Leaves are alternate; blades linear, 1-2 mm wide, fleshy, usually not swollen at base, apex acuminate, forming a rather firm spine, 1-1.5(-2.2) mm long. Flowers are Inconspicuous, white, yellowish or greenish, cup shaped, in the leaf axils. The fruit/seeds have small, brownish capsules, usually with five spreading membranous, veined wings. A single plant can produce up to 200,000 seeds.

Ecology

It grows in disturbed soils such as agricultural fields, irrigation canals and roadside shoulders and ditches. Plants thrive in salty and alkaline soils but will generally be outcompeted by natives in undisturbed habitats. Flowering occurs from September-April.

Distribution and habitat

Salsola sp is native to Europe, North Africa, the Middle East, Central Asia, China and Australia. The peregrinating (highly traveled) plant also grows abundantly in Afghanistan, Argentina, Australia, Canada, Chile, China, Egypt, Greece, Hawaii, Hungary, Indonesia, Iran, Italy, Japan, Lebanon, Mexico, Morocco, New Zealand, Norway, Pakistan, Poland, South Africa and Turkey.

It’s a highly problematic, tough, unpalatable plant that clogs up storm water channels and competes with native species. It can rapidly colonise new areas, especially overgrazed, bare and eroded soil. The plants are unpalatable leading to selective grazing by domestic stock which exacerbates existing overgrazing and opens the way for further tumbleweed invasion.

As it rolls down the road, tumbleweeds do what they do best, disperse seeds, which typically number 250,000 per plant. Seeds are unusual in that they lack any protective coat or stored food reserves. Instead, each seed is a coiled, embryonic plant wrapped in a thin membrane. To survive winter without a warm coat, the plant does not germinate until warm weather arrives.

Scientific Name: Opuntia ficus-indica (L.) Mill

Family: Cactaceae

Common names: Turksvye, Sweet prickly pear, Boere-turksvy.

Opuntia ficus-indica was brought into the country for its use as hedging, animal feed and for its delicious, juicy fruit. These plants can be a very aggressive alien species. A serious infestation can render a veld useless. Cattle and wild eat the leaves but avoid the fruit because of the irritating thorns.

Distribution:

This plant is believed to have originated in the Americas, specifically in Mexico. It has naturalised in Australia, southern Europe, Africa, southern Asia, southern USA and some oceanic islands with warm climates.

Description:

Opuntia ficus-indica is a succulent shrub or tree ranging 1.5-3 m but it can grow up to 5 m. It develops a sturdy trunk with age. The branches (cladodes) are flattened, grey to grey-green. The branches are 30-60 cm long and 6-15 cm wide. Its younger branches arch upwards. The leaves are minute and are shed early. The flowers are conspicuous, bright yellow or orange, red in colour. It bears succulent edible berries which are reddish when ripe, about 8 cm long and covered with clusters of minute spines.

Conservation status:

Opuntia ficus-indica is a category 1b plant in terms of the National Environmental Management: Biodiversity Act, 10 of 2004. This means that the plant must be controlled and where possible eradicated and removed. These plants are deemed to have such a high invasive potential that infestations can qualify to be placed under a government sponsored invasive species management programme. No permits will be issued. No new plants may be planted. Spineless cactus pear cultivars and selections are not listed. The fruit of the sweet prickly pear is not listed if used for human consumption.