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 Asparagus aethiopicus, Sprenger's asparagus,
is a plant native to the Cape Provinces and the Northern Provinces of South
Africa. Often used as an ornamental
plant, it is considered an invasive weed in many locations. Asparagus fern, asparagus grass and
foxtail fern are common names; but, it is not related to true ferns. A.
aethiopicus has been confused with A. densiflorus, now regarded as a separate species, so
that information about A. aethiopicus
will often be found under the name A.
densiflorus. The species
was originally described by Carl Linnaeus in 1767. The attribution "Sprenger's
Asparagus," refers to Carl Ludwig Sprenger who promoted it as
an ornamental plant in Europe.
Asparagus
aethiopicus is a perennial herb with green aerial stems tjat are
lightlycovered with spines. The
leaves are actually leaf-like cladodes, 0.8–2 cm long and
0.1-0.2 cm wide. They extend in
groups of four or more from the stem.
In spring, there are small white or pink flowers that occur in
clusters off the stem. Small round
berries 0.5 cm in diameter with a black 3 mm diameter seed are
initially green, but then turn red in winter. There is a mat of fibrous roots with bulbous water storage
tubers that extend from a hard crown at the base of the leaves. This crown including pieces remaining in
the ground may resprout.
Asparagus aethiopicus is native to
southern regions of South Africa in the Western Cape, Eastern Cape and the
Northern Provinces. Its natural
habitat is rocky shale slopes and coastal scrub, in dry land areas.
In the United States, this plant is a weed in California,
Florida and Hawaii, but it is spreading.
It is also considered a weed in New Zealand, and has become
established around major urban areas in Australia including Sydney,
Wollongong, the Central Coast, Southeastern Queensland, and Adelaide, as well
as the Lord Howe and Norfolk islands.
Seeds are spread by fruit-eating birds and during the disposal of
garden refuse. It can be eradicated
using herbicides. but manual removal is difficult because of tiny thorns and
deep roots. However, the non-water
storage tubers can be left in the ground as they do not sprout.
There are no biological controls for
the asparagus fern, but treatment with Glyphosate at 1% solution with 0.25%
surfactant has shown good control,
especially if applied more than once.
REFERENCES:
Gibbs Russell, G. E., W. G. M. Welman, E.
Retief, K. L. Immelman, G. Germishuizen, B. J. Pienaar, M. Van Wyk &
A. Nicholas. 1987. List of species of southern African plants.
Memoirs of the Botanical Survey of South Africa 2(1–2): 1–152 (pt. 1), 1–270.
Goldblatt,
P. & J. Manning. 2002. Cape plants: a conspectus of the Cape
flora of South Africa. Strelitzia 9.
National Botanical Institute, Pretoria and Missouri Botanical Garden, St
Louis.
Jackson,
W.P.U. 1990. Origins and meanings of names of South
African plant genera. University of
Cape Town, South Africa.
Manning,
J. 2007. Field guide to Fynbos.
Struik Publishers, Cape Town, South Africa
Romand-Monnier,
F. & L. von Staden. 2013. Asparagus aethiopicus. The IUCN Red List of Threatened Species
2013
Van Wyk, B.E.
& N. Gericke. 2000.
People's plants. Briza
Publications, Pretoria. South Africa.
Von
Staden, L. 2012. Asparagus aethiopicus L. National Assessment: Red List of South African Plants version
2017.1.
Wolff, Mark A. 1999. Winning the war of Weeds: The Essential
Gardener's Guide to Weed Identification and Control. Kenthurst, New South Wales: Kangaroo
Press. p. 43.
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