Scientific name

Cereus jamacaruDC

Synonyms

Piptanthocereus jamacaru; Piptanthocereus cabralensis; Cereus calcirupicola; Piptanthocereus calcirupicola; Cereus calcirupicola; Piptanthocereus cipoensis; Cereus calcirupicola; Piptanthocereus goiasensis; Cereus goiasensis

Common names

Queen-of-the night

Family

Cactaceae

Origin

Cereus jamacaru is native to north-eastern Brazil

Naturalised distribution (global)

Locations within which Cereus jamacaru is naturalised include southern Africa.

Introduced, naturalised or invasive in East Africa

Cereus jamacaru is invasive in parts of Kenya (A.B.R. Witt pers. obs.) and is naturalised in eastern Tanzania (East African Herbarium plants database, 2011). The editors are not aware of records of the introduction of C. jamacaru to Uganda although it is likely to be present in this country.

Habitat

Rocky outcrops and the savanna.

Description

Cereus jamacaru is spiny tree normally growing to 7 metres, though it can sometimes grow up to 15 metres high. It has thick, succulent branches arising from a short, woody truck. Spines are in groups of 5 to 10 and its cut stems do not exude a milky latex. Branches are green to blue green with prominent ribs which are sometimes broken and wavy.

C. jamacaru has no leaves.

Flowers are white and conspicuous (at night), measuring up to 25 cm long.

The fruit is a berry, yellowish pink, pink or red in colour measuring up to 6 cm long. It is white inside with small black seeds.

Reproduction and dispersal

Most plants are spread through vegetative means.

Economic and other uses

Cereus jamacaru is cultivated as an ornamental. It also forms a good hedge. However, these uses cannot compensate for this plant's overall negative impacts.

Environmental and other impacts

Cereus jamacaru spreads into natural vegetation threatening indigenous vegetation. It has been listed as 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).

Management

The precise management measures adopted for any plant invasion will depend upon factors such as the terrain, the cost and availability of labour, the severity of the infestation and the presence of other invasive species.

The best form of invasive species management is prevention. If prevention is no longer possible, it is best to treat the weed infestations when they are small to prevent them from establishing (early detection and rapid response). Controlling the weed before it seeds will reduce future problems. Control is generally best applied to the least infested areas before dense infestations are tackled. Consistent follow-up work is required for sustainable management.

Two insects, a mealybug, Hypogeococcus pungens, and a stem-boring cerambycid beetle, Alcidion cereicola, from South America have been effective biological control agents for this species.

Legislation

Not listed as a noxious weed by the state or governments in Kenya, Tanzania and Uganda.

Notes

There is some confusion about the identification of this species. Some sources say that the naturalised plant in East  Africa is Cereus peruvianus  (Dharani 2002).

References

Dharani, N. (2002). Field guide to common trees and shurbs of East Africa. Struik, Cape Town, South Africa.

Henderson, L. (2001).  Alien weeds and invasive plants. A complete guide to declared weeds and invaders in South Africa.  Plant Protection Research Institute Handbook No. 12, 300pp. PPR, ARC South Africa.

Editors

Agnes Lusweti, National Museums of Kenya; Emily Wabuyele, National Museums of Kenya, Paul Ssegawa, Makerere University; John Mauremootoo, BioNET-INTERNATIONAL Secretariat - UK.

Acknowledgments

This fact sheet is adapted from The Environmental Weeds of Australia by Sheldon Navie and Steve Adkins, Centre for Biological Information Technology, University of Queensland. We recognise the support from the National Museums of Kenya, Tropical Pesticides Research Institute (TPRI) - Tanzania and Makerere University, Uganda. This activity was undertaken as part of the BioNET-EAFRINET UVIMA Project (Taxonomy for Development in East Africa).

Contact

BioNET-EAFRINET Regional Coordinator: [email protected]