Cape tulip (one-leaf)

Common name:

  • Cape tulip (one leaf)

Scientific name:

  • Moraea flaccida (Sweet) Steud.

Other scientific name:

  • Homeria flaccida Sweet

Plant status

Catchment management authority boundaries

Regionally prohibited in the Mallee and Goulburn Broken catchments.

Regionally controlled in the Wimmera, Glenelg Hopkins, North Central, Corangamite, North East, East Gippsland, West Gippsland, Port Phillip and Westernport catchments.

Restricted in no areas in Victoria.

Plant biology

Appearance

Herbaceous plant  — Forb (flowering herbaceous plant  — not a grass)

Description

Cape tulip (one-leaf) is an erect perennial herb that grows from a bulb.

Stems

Stems are stiff, erect, somewhat zigzagged and branched near the summit 30 to 60cm high.

Corms (swollen, underground stems which stores food for the plant) are white, about 1 to 2cm in diameter, enclosed in a light brown fibrous tunic. One to three new corms are produced above the old corm each year.

Leaves

Cape tulip (one-leaf) usually only has 1 leaf per plant which is flat, ribbed, 1 to 2cm wide and 1m long.

Flowers

Flowers of Cape tulip (one-leaf) are orange or salmon pink(occasionally yellow) with a yellow patch in the centre. They are 3 to 5cm diameter and appear in small clusters at the ends of the branches. Flowers have 6 petal-like segments 2.6 to 4cm long.

Fruit

Green at first, turning brown when mature  — a thin 3-valved capsule to 5cm long, opening at the top to discharge numerous brown irregularly shaped seeds to 2mm long.

Seeds

Seeds are brown, irregularly shaped that grow to 2mm long.

Growth and lifecycle

Method of reproduction and dispersal

The weed is dispersed mainly by the movement of corms and seeds which contaminate farm produce, machinery and attach to the wool and feet of animals.

The dried plants, with seed capsules still intact, break off at ground level and are blown about by wind and carried by running water. Movement of gravel or soil from infested sites can also spread the corms and seeds.

Another major method of dispersal of Cape tulip (one-leaf) occurs in hay or silage cut from infested paddocks.

Rate of growth and spread

Plants are 2 to 3 years old before they flower and set seed.

Seedbank propagule persistence

Dense infestations can produce up to 7000 corms per square metre.

Seeds remain viable after passing through stock.

Seeds of Cape tulip (one-leaf) do not live long in the soil. Most germinate in the autumn following formation, and those that do not germinate during that season die.

Seeds germinate more readily on the soil surface than when buried. Seeds buried at 5cm fail to produce seedlings. Corms show longer viability than seeds.

The weed can produce up to 150 seeds per capsule with 8 capsules per plant amounting to 1200 seeds per plant.

Preferred habitat

Cape tulip (one-leaf) prefers semi-arid and sub-humid, subtropical scrublands on a wide range of soil types. It grows mostly in areas with annual rainfall of less than 600mm and does not establish well in shaded sites.

Distribution

In Victoria, the weed grows in isolated patches, although it is extensive in some cases throughout the Wimmera, Western District and around Melbourne.

Growth calendar

The icons on the following table represent the times of year for flowering, seeding, germination, the dormancy period of Cape tulip (one-leaf) and also the optimum time for treatment.

 JanFebMarAprMayJunJulAugSepOctNovDec
Flowering        Flowering iconFlowering icon  
Seeding          Seeding iconSeeding icon
Germination  Germination iconGermination iconGermination iconGermination icon      
DormancyDormancy iconDormancy iconDormancy icon        Dormancy icon
Treatment   Treatment iconTreatment iconTreatment iconTreatment iconTreatment icon    

Impact

Impact on ecosystems and waterways

Cape tulip (one-leaf) grows best in open environments, such as grasslands and pasture, where it competes with and replaces desirable plants.

The plant severely impedes the growth and regeneration of indigenous ground flora.

Aerial parts of the plant are only present for 5 to 6 months each year. However, the root system, while not deep, is fine and fibrous.

Agricultural and economic impacts

All parts of Cape tulip (one-leaf) are toxic, although it is thought that the green leaves are far more dangerous than other parts of the plant.

It is poisonous to cattle, sheep and goats but is generally avoided by grazing animals. This results in desirable pasture plants being replaced by this weed and stock not grazing valuable pasture that is growing within the infested area.

Social value and health impacts

All parts of the plant are poisonous if ingested.

Management

Prescribed measures for the control of noxious weeds:

  • application of a registered herbicide.

Read about prescribed measures for the control of noxious weeds.

Other management techniques

Changes in land use practices and spread prevention may also support Cape tulip (one leaf) management after implementing the prescribed measures.

Page last updated: 25 Jun 2020