silver-leaf nightshade

Solanum elaeagnifolium
Herb
Alternate
Simple
Purple
Green

Perennial herbs up to 50 cm tall, vegetative growth usually annual, erect, branched above, usually armed with straight, fine, reddish prickles 2-5 mm long, usually on stems, occasionally on petioles, leaves, and calyx, general aspect silvery green, rarely reddish brown, forming colonies from underground root system.

Common names 
Also known as: White Horse Nettle,
Family 
Solanaceae
Deciduous 
No
Flowering time 
Spring to Autumn
Native/Exotic 
Exotic
Origin 
Native to southern South America and possibly also parts of North America
Notifiable 
No
State declaration 
Category 3 - Must not be distributed or disposed. This means it must not be released into the environment unless the distribution or disposal is authorised in a regulation or under a permit.
Council declaration 
As per State Declaration
Known distribution 

Silverleaf nightshade is now found throughout most parts of NSW, south east Queensland, Victoria, South Australia and Western Australia.

Habitat 

S. elaeagnifolium is adapted to a wide range of habitats, but appears mostly in areas of relatively low annual rainfall (300-500 mm). The weed thrives on disturbed land and, in addition to crop lands, areas particularly prone to invasion include roads, water furrows and rivers, and livestock corrals.

Habit 

Erect, clonal perennial herb to 1 m, often suckering, silvery-green, rarely rusty-green, densely pubescent with stellate hairs; prickles 2–5 mm long, usually on stems, less common elsewhere.

Impact and control methods 

Silver-leaved nightshade (Solanum elaeagnifolium) is a weed of crops and cultivation, pastures, roadsides, disturbed sites and waste areas in semi-arid, temperate and sub-tropical regions. While it is primarily a weed of agricultural areas, silver-leaved nightshade is also a weed of native pastures and rangeland plant communities, and is occasionally also found in other natural environments. During a recent survey, it was listed as a priority environmental weed in four Natural Resource Management regions.

Stem and leaves 

The typical silverleaf nightshade is an erect, multi-stemmed perennial plant growing up to 60cm. The leaves are 5-10 cm long, have wavy edges and are silvery-green with a paler undersurface. Short, brown-yellow spines approximately 5 mm long occur on the stems and petioles (short stems attaching the leaves to main stems)

Flowers and fruits 

Flowers up to 25 mm in diameter have five purple or white petals with five yellow stamens 7-9 mm in length. Berries are green striped, round, smooth, commonly 1 cm in diameter which turn yellow-orange when ripe. Green berries that are only four weeks old and as small as 7 mm in diameter can contain viable seeds. Plants produce up to 60 berries, each containing 10-210 seeds.

Reproduction and dispersal 

Long-distance spread can occur both vegetatively, from cut root sections, and via seeds. Dispersal is aggravated by agricultural practices (contaminated vehicles and implements) and via agricultural produce, notably seeds that are harvested with certain crops.

Similar species 

Quena and Western nightshade