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Fringed Spider Flower (DBIRD_NT)

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					Agnote
                                                                      799
                                                                      No. F92

                                                                      July 2001

                                                                      Agdex No: 642

                                                                      ISSN No: 0157-8243




Fringed Spider Flower
(Cleome rutidosperma)
M. P. Schmid, Weeds Branch, Darwin
Family: Capparaceae
Class of Declared Weed: A (to be eradicated) and
                       C (not to be introduced to the Territory)

INTRODUCTION

Fringed Spider Flower (Cleome rutidosperma) is native to tropical Africa, and occurs in Central
America, Southeast Asia, including Timor (Soerjani et al. 1987). It is recognised as a significant
weed that causes problems in cropping areas and natural ecosystems. It has been recorded on
Christmas Island, an Australian territory, however the first Australian mainland incursion was
discovered in August 2000, near Darwin's Fort Hill wharf.

It has subsequently been discovered at 16 sites in suburban and rural Darwin. At the time of
publication, all mainland sites were subject to eradication programs.

DESCRIPTION

Fringed spider flower can be
clearly identified by the following
characteristics:

•   Prostrate spreading herb,
    occasionally erect when
    growing with competing
    species such as gamba
    grass and spiny head sida.
•   Angular      stems      with
    longitudinal grooves; colour
    of mature stems is maroon
    with younger stems being a
    light green.
•   Trifoliate leaves with ovate to lanceolate leaflets 2.5 cm long and 1 cm wide.
•   The flowers are borne on a long (25 mm) pedicel (stem) and are blue to mauve in colour
    with four petals, six stamens and approximately 6 mm in size.
•   Fruit is identified by its elongate-linear capsule with an average length of 60 mm and
    diameter of 4-5 mm. The fruit is light green in colour and each capsule contains an average
    of 100 tiny black seeds when mature.
•   Seeds are 1.8-2.0 mm in diameter, ribbed with a white elaiosome.
                                                 2

Plants can grow rapidly and a seedling can germinate and set flower within six weeks under
ideal growing conditions, such as those experienced during the Top End wet season.

IMPORTANCE

Fringed spider flower is on the North Australian Quarantine Service weeds target list as a
category one weed “weeds posing a very serious threat”.

In Asia, fringed spider flower is considered an agricultural weed, (Soerjani et al. 1987) which
can reduce crop yields and increase production costs. It also invades disturbed areas and has
negative impact on biodiversity (Bayley 2000, Du Puy and Telford 1993).

Anecdotal evidence indicates that seed production of fringed spider flower is prolific, giving it an
advantage as a competitive species.

CONTROL

The Department of Infrastructure, Planning and Environment weeds officers conduct regular
surveys of known outbreaks. At these locations, control is by hand pulling or herbicide
treatment, depending on the size of the infestation. It is important that any known sightings of
this weed are reported immediately to DIPE. Through vigilance of people involved in the
horticultural and nursery industries, along with the home gardener, eradication of this weed is
achievable.

If you find a plant fitting the description of Fringed Spider Flower, please report it to DIPE
Weeds Branch Darwin, Jabiru, Katherine, Timber Creek, Borroloola, Tennant Creek or Alice
Springs.

REFERENCES

Bayley, D. (2000). Efficient Weed Management. State of New South Wales. NSW Agriculture
        pp. 5.

Du Puy, D.J. and Telford, I.R.H. (1993). Capparaceae Flora of Australia 50: 169-170.

Soerjani, M., Kostermans, A.J.G.H., and Tjitrosoepomo, G. (1987). Weeds of Rice in Indonesia.
        Balai Pustaka, Jakarta.




Please visit us on our website at www.primaryindustry.nt.gov.au




Published: Tuesday 24 July 2001.
                                                       3




Drawing courtesy of Weeds of Rice in Indonesia. M. Soerjani et al. (1987).

While all care has been taken to ensure that information contained in this Agnote is true and correct at the time
of publication, the Northern Territory of Australia gives no warranty or assurance, and makes no representation
as to the accuracy of any information or advice contained in this publication, or that it is suitable for your
intended use. No serious, business or investment decisions should be made in reliance on this information
without obtaining independent/or professional advice in relation to your particular situation.

				
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Description: Fringed Spider Flower (DBIRD_NT)