INTRODUCTION

1. The Jumping cholla (Cylindropuntia fulgida (Engelm.) F.M.Knuth var. fulgida ), a new invasive species of the semi-arid areas of Matebeleland in Zimbabwe Professor A. B. Mashingaidze2 and Dr Joyce Ndlovu2 1Director, Invasive Species Research and Management Unit, Chinhoyi University of Technology, P. Bag 7724, Chinhoyi, Zimbabwe 2Seniour Lecturer, School of Natural Sciences and Mathematics, Department of Biology, Chinhoyi University of Technology, P. Bag 7724, Chinhoyi, Zimbabwe ABSTRACT: The Jumping cholla or Chain-fruit cholla (Cylindropuntiafulgida) is a new invasive cactus species that is invading the semi-arid districts of Matebeleland. The weed was introduced most likely as a ornamental plant by landscape garden enthusiasts and there are reports that local villages in Beit-Bridge and Gwanda district planted it around their homesteads in the belief that it protected them against lighting strikes. The main method of spread is though vegetative propagation when segments of the thony cactus detach themselves from the main plant at the slightest contact and attach themselves to passing human, animal, bird and vehicular traffic (hence jumping cholla) and are carried to new areas. The detached segments easily re-root, despite the aridity of the environment, because they are succulent (store water and nutrients) and the jumping cholla establishes in new areas. The weed produces white and pink flowers displayed at the tips of segments or old fruits that remain attached to terminal segments (hence chain fruit cholla or hanging chain fruit cholla), but sexual propagation is rare since most of the seeds produced within the fruits are sterile. The cactus is covered with 2-3cm silvery yellow spines that have backward facing barbs making them difficult and extremely painful to remove once they imbed themselves into the flesh. The plant forms thick impregnable thickets that deny farmers and their animals access to grazing areas, water holes and crop fields, injure and kill domestic and wild animals. Villagers are currently slashing and burying the weed but the most sustainable method of controlling the weed is the introduction a classical biological control agent that is very specific for the control of the jumping cholla, the cholla biotype of the cochineal insect Dactylopiustomentosus, which feeds on the plant and destroys it. DESCRIPTION (continued) additional protection and are very difficult to remove, causing irritation and skin disorders (irritant contact dermatitis) in humans and animals that come into contact with the weed. The major problem to communities in Matebeleland where it is now endemic is that it forms impregnable physical barriers that deny them access to grazing land, agricultural land and watering points. The spines cause injury to domestic and wild animals and so far there are reports that villagers have lost cattle, donkeys and goats to the weed, valuable assets in the semi-pastoral agricultural system that sustains livelihoods in semi-arid areas of Zimbabwe. INTRODUCTION The jumping cholla ((Cylindropuntiafulgida var. fulgida (Engelm.) F.M.Knuth var. fulgida ) has been receiving a lot attention from the local press and the legislature in Zimbabwe because of its declaration by the Environmental Management Agency as a noxious invasive species and the social and economic problems that the weed is reportedly causing to villagers in Matebeleland South. The jumping cholla is being commonly misidentified as Rosea cactus which is the common name of another similar cylindropuntia species, Opuntiarosea, also known as the Hudson Pear. This confusion on the nomenclature and taxonomic identification of the jumping cholla continues despite fact that the chain-fruit cholla or jumping chollaCylindropuntiafulgida(Engelm.) F.M.Knuth var. fulgidaorOpuntiafulgida (Engelm) has been taxonomically confirmed as the species that has invaded South Africa and Zimbabwe (Henderson and Zimmermann, 2003; Paterson et al., 2011). The species is reported by EMA to have invaded more than 3000 hectares of land in Gwanda and Beitbridgedistrit of Matebeleland South province in Zimbabwe and is spreading to other semi-arid districts of Bulilima and Insiza. This objective of this review is to clarify misconceptions about the identity, origin and biology of the weed to bring all practitioners and scientists to the same level of understanding of what they are dealing with and facilitate informed and effective management of this invasive species to the benefit of thousands of smallholder farmers in Matebeleland South, whose livelihoods and economic well-being are severely being disrupted by the weed. TAXONOMY AND ORIGIN OF JUMPING CHOLLA The jumping cholla cactus belongs to the family Cactaceae that comprise approximately 1 600 species and 130 genera sub-divided into four sub-families Pereskioideae, Opuntioideae, Cactoideae) and Maihuenioideae (Anderson, 2001). The sub-family Opuntioideae to which the jumbingchola belongs, is sub-divided into five tribes Tephrocacteae, Pterocacteae, Austrocylindropuntieae, Cylindropuntieae and Opuntieae (Wallace and Dickie, 2002). The two largest genera within the Opuntiod subfamily are the flat stemmed Opuntia (29 species) and the terete (cylindrical but usually slightly tapering at both ends) stemmed Cylindropuntia (12 species) (Griffith and Potter, 2009). The jumbingcholla is a Cylindropuntia species. TABLE 1: Classification of the jumping cholla (Cylindropuntiafulgida (Engelm.) F.M. Knuth) (USDA Natural Resources Conservation Service, 2014) Kingdom: Plantae Subdivision: Tracheobionta – Vascular Plant Super-division: Spermatophyta - Seed Plant Division:Magnoliophyta - Flowering Plant Class: Magnoliopsida – Dicotyledon Subclass:Caryophyllidae Order: Caryophyllales Family: Cactaceae – Cactus family Genus: Cylindropuntia (Engelm.) Kreuzinger - cholla Species: Cylindropuntiafulgida (Engelm.) F.M. Knuth – jumbingcholla Variety: Cylindropuntiafulgida (Engelm.) F.M. Knuth var. fulgida – jumping cholla Synonym: OpuntiafulgidaEngelm. The cactus species is native to the arid deserts of Sonoran Desert in north east Mexico and the south eastern United States in the Colorado Desert of California, the Yuma Desert of Arizona and the Mojave Desert in Southern Nevada and Utah. It has spread throughout the world including Africa and Australia semi-arid regions , where it is a problematic invasive species. Fig 1: Close up of jumping cholla spine with backward facing barbs that make it extremely painful and difficult to remove once they are imbedded in flesh Fig 2: Cylindropuntia fulgida on a rocky outcrop near Manama Mission in Gwanda district, Matebeleland South Province, Zimbabwe (Courtesy of Hyde, Wursten and Ballings, 2007) MANAGEMENT OPTIONS FOR THE JUMPING CHOLLA Currently villagers in Matebelelend are being organized to slash the invasive species and collect plant material and bury it in deep pits. Although the method is effective for removing small infestations of the weed, it is labour intensive, time consuming and expensive to effectively remove the weed from the large areas that it has invaded. EMA has asked for US $ 2.5 million for this exercise but such resources have not materialized from a cash-strapped government . In addition any small pieces of the plant that remain can be a source of re-infestation. Phloem translocated phenoxy herbicides applied as sprays or injections such as MSMA, triclopyr, picloram+triclopyr and amitrole are effective against the jumping cholla but need technical know-how and are an expensive option (Mashingaidze and Chivinge, 1995). The cheapest and most sustainable method of managing the weed is for quarantine authorities to introduce the biological control agent for Cylindropuntia fulgida, the cholla biotype of the cochineal insect Dactylopius tomentosus, whose females and nymphs feed on the plant, probably injecting toxins into plant tissues, causing the destruction of the plant. REFERENCES Henderson L. and H. G. Zimmermann 2003. (Opuntia fulgida Engelm) misidentified as rosea cactus (Opuntia rosea DC) in South Africa. South African Journal of Plant and Soil 20 (1): 46-47. Paterson I. D., J.H. Hoffman, H. Klein, C. W. Mathege, S. Neser and H.G. Zimmermann 2011. Biological control of Cactaceae in South Africa. African Entomology 19:230-246. Mashingaidze A. B and O. A. Chivinge 1995. Demystifying the dioxin controversy associated with the use of 2.4 D to control of water hyacinth (Eichhornia crassipes) in Lake Chivero in Zimbabwe. Zimbabwe Journal of Agricultural Research 33 (1): 1-11. . DESCRIPTION AND IMPACT OF THE WEED The Jumping cholla is an arborescent (tree –like) low branching cylindrical cactus species that can grow to a height of 4-5 metres with drooping branches of chain fruits (hence chain fruit cholla). Stems are light green and covered with small wart like projections , measuring 6-9 mm in diameter, called tubercles. To reduce transpiration, leaves have been reduced to spines, 6-12 of which arise from small light to dark coloured bumps called areoles on the surface of stems and segments. Young branches are completely covered with silvery to yellow spines that darken to a grey colour with age. Smaller detachable bristles , called glochids, grow out of the areoles. Glochids provide