invasive weed 3: Silver-leaf nightshade

Name: Silver-leaf nightshade
Scientific name: Solanum elaeagnifolium
Other names: Silver-leaf nettle, silver-leaf bitter apple
Level: Category 3 restricted invasive plant

The Silver-leaf nightshade is a deep-rooted perennial plant that is native to North America. This multi-stemmed plant that grows up to 60cm tall. Small spines up to 5mm long grow on the stems and petioles and leaves are silvery green with pale underside, 5-10cm long and have wavy edges. Silver-leaf nightshade has 5 purple/white flowers up to 25mm in diameter with 5 yellow stamens. Berries of the nightshade plant are green striped, round and smooth that turns yellow/orange when ripe and seeds are light brown, rounded, flattened with irregular surface (AJ, 1988).

Figure 1: Silver-leaf Nightshade berries

Figure 2: Nightshade leaves and stem with spines 

Figure 3: Nightshade flower

Silver-leaf Nightshade disperses its seeds in a number of ways. Seeds can be spread by animals such as birds as they feed on the fruit and take the seeds to new areas. During summertime, plants can grow from seeds and roots while in wintertime, the plant grows mostly from the roots. Roots can be spread by cultivation by the machinery as new plants can grow from roots as small as 1cm. This plant can grow in any soil type allowing it to have a wide range of habitats and can be found in Southern east Queensland (Stanton & Lemerle, 2012).

Silver-leaf Nightshade is a category level 3 invasive plant and is difficult to control/remove. The Silver-leaf Nightshade has an extensive interconnecting root system which is difficult to remove as they have the capacity to regenerate from root fragments. Good farm hygiene is mandatory to help stop the spread of seeds and roots. There is currently no biological control for this weed.

References

AJ, W. 1988, "Prospects for the biological control of silver-leaf nightshade, Solanum elaeagrifolium, in Australia",

Stanton, R., Wu, H. & Lemerle, D. 2012, "Factors Affecting Silverleaf Nightshade (Solanum elaeagnifolium) Germination", Weed Science, vol. 60, no. 1, pp. 42-47.

https://www.business.qld.gov.au/industries/farms-fishing-forestry/agriculture/land-management/health-pests-weeds-diseases/weeds-diseases/invasive-plants/restricted/silver-leaf-nightshade retrieved 27/04/2020