The Jumping cholla (Cylindropuntia fulgida (Engelm.) F.M.Knuth var

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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 (Cylindropuntia fulgida) 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 Dactylopius tomentosus, which feeds on the plant and destroys it.
INTRODUCTION
DESCRIPTION (continued)
The jumping cholla ((Cylindropuntia fulgida var. fulgida (Engelm.) F.M.Knuth var.
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.
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, Opuntia rosea, 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 cholla Cylindropuntia
fulgida (Engelm.) F.M.Knuth var. fulgida or Opuntia fulgida (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 Beitbridge
distrit of Matebeleland South province in Zimbabwe and is spreading to other semiarid 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.
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
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 jumbing chola 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 jumbing cholla is a Cylindropuntia species.
TABLE 1: Classification of the jumping cholla (Cylindropuntia fulgida (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:
Cylindropuntia fulgida (Engelm.) F.M. Knuth – jumbing cholla
Variety:
Cylindropuntia fulgida (Engelm.) F.M. Knuth var. fulgida –
jumping cholla
Synonym:
Opuntia fulgida Engelm.
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 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
.
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
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.
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