Sida acuta (sida).

Abstract Originating in central America, the small perennial shrub, S. acuta has successfully invaded the tropics worldwide, largely as a contaminant in pasture seed. Its tolerance of a wide range of growing conditions has enabled S. acuta to become established in these diverse habitats. It infests various crops and habitats, but has been most problematic in pastures and rangelands, particularly in savannah-type biomes with pronounced wet and dry seasons. It can form dense monospecific stands in these regions, and has had a pronounced economic impact in northern Australia, Papua New Guinea and many Pacific Islands. Since the late 1980s, the foliage-feeding chrysomelid beetle Calligrapha pantherina has been introduced into many areas as a biological control agent specific to S. acuta and related Sida species. Introductions of C. pantherina have led to successes in control of S. acuta infestations, reducing seed production, and resulting in restoration of native vegetation in many cases.