The first infestations in Australia of a highly invasive weed have recently been discovered on the Mid North Coast and Councils from Nambucca to Tweed Heads are now on high alert.

Tropical Soda Apple (Solanum viarum from the Solanceae family) is a very invasive weed which has been found in the Upper Macleay near Kempsey. This is the first time this plant has been recorded to exist in New South Wales and possibly Australia. Specimens were sent to the Royal Botanic Gardens, where it was correctly identified by a Dr Wilson who curates the Solanaceae.

The plant is described as being a perennial shrub that grows from 1-2 metres in height with leaves and stems containing large white to yellow thorn-like prickles. Flowers are white. Immature fruits are similar in colour to a water melon, which turn yellow when mature. They are about three centimetres in diameter.

Tropical Soda Apple is native to Brazil and Argentina, but has been declared a noxious weed in several states in the USA. It has the ability to quickly invade pastures, but can also occur in woody areas.

The primary mode of dispersal is through livestock or wildlife feeding on the mature fruit, which can contain 200-400 seeds each.

There is no registered herbicide to control Tropical Soda Apple. Weeding or pulling the plant out is a good control method to prevent flowering and the plant setting seed, however, this can be difficult due to nature of the terrain and soil where the plant is found growing.