Terrestrial Invasives

Cardiospermum grandiflorum

Cardiospermum grandiflorumBalloon vine

Common Name 
Balloon vine
Legal Status 
Emerging Weed
NEMBA 1b
Description

A perennial, slightly woody subtropical climber which occurs naturally in tropical South America. Its climbing tendrils grow 3-5m or higher, often draping themselves over trees. The stems are usually covered with bristly hairs. Easily recognisable with its compound leaf, which has toothed, light green, thin textured, hairy leaflets. Flower stalks bearing small white flowers arise from the leaf axils of the plant. The fruit consists of a roughly spherical, balloon-like, thin-walled capsule about 60mm long, which contains several large black seeds.

Where does this species come from? 
Cardiospermum grandiflorum is native to the tropical America (Brazil and eastern Argentina) though its native range may extend into southern Mexico and the Caribbean.

Why is it a problem? 
Cardiospermum grandiflorum forms dense infestations that outcompete indigenous vegetation. It is a major weed in riparian zones (banks of watercourses) in South Africa. It is rapidly spreading beyond urban areas in East Africa. Although not a very serious problem yet in the region, it has massive potential for further spread. It can smother native plants and prevent the free movement of wildlife so has great potential to negatively impact upon biodiversity. C. grandiflorum has been included in the Global Invasive Species Database (GISD 2008). It has been listed as a noxious weed in South Africa (prohibited plants that must be controlled. They serve no economic purpose and possess characteristics that are harmful to humans, animals or the environment) and in in the Australian states of New South Wales and Queensland, Australia.

Means of reproduction? 
Cardiospermum grandiflorum reproduces by seeds, which are transported by wind and water, mostly while attached to membranous inner walls of the fruit.