Municipal Plant of the Month – Lantana spp: ALL seed-producing species and seed-producing hybrids are considered one of the 10 worst weeds in the world and comes in at number four in South Africa. Not only is Lantana very invasive and classified as a transformer but it is also one of the most common causes of livestock poisoning in South Africa. All Lantanas are classified as a Category 1b invasive species which must be removed and destroyed. Any form of trade or planting is strictly prohibited.
Identification: Lantana is easily identified almost all year round by the very pretty clusters of multi-coloured flowers that may vary from pink, red, crimson, orange, yellow or white. The flower head is flat and compact often with many colours in one flower head. The fruits turn black when ripe and is a firm favourite with birds and other animals such as rodents and monkeys and appear to be non-toxic to these animals. These animals act as seed dispersal agents. The leaves are dark green and stiff with serrated margins. When crushed they exude a pungent unpleasant odour. The stems are very thorny.
Impacts: Lantana is a habitat transformer, forming thick impenetrable stands along forest margins, degraded land, road reserves, etc. Where the plants proliferate, they shade out and outgrow any indigenous plants and in addition, Lantana excretes chemicals which reduce the growth of surrounding plants by inhibiting germination and root elongation thus impacting heavily on biodiversity. Dense stands pose a fire risk as a result of increased biomass and fuel load.
Control: Chop down and treat the stumps and re-growth with a registered herbicide. Caution must be exercised that no cuttings are left behind with a node in contact with the soil as these readily take root and establish new plants. The poisons Chopper or Kaput are recommended as herbicides suitable for stump treatment and re-growth can be sprayed with a 3% mix of “Roundup” or other glyphosate herbicides.