Environmental Weeds

Leonotis nepetifolia - Lions Tail

Leonotis nepetifolia

Family: Lamiaceae

Origin: Native of tropical Africa.

Flowers/Seedhead: In clusters to 6 cm wide; flowers subtended by pointed leafy bracts. Flowers mostly autumn in tropics.

Description: Erect annual herb to 3 m high. Stems 4-angled, with white short hairs. Leaves decrease in size from the base of the plant to the top. Fruit consisting of 4 seed-like nutlets. Nutlets brown, 3-keeled, 3-3.5 mm long.

Distinguishing features: Distinguished by opposite leaves, 6-12 cm long, 3-6 cm wide, margins toothed; flowerhead of 2-4 spherical clusters of numerous orange flowers spaced at intervals towards the top of the stem.

Dispersal: Nutlets by water movement and in mud.

Notes: Garden escape. Capable of forming large colonies. It is a serious weed of rice and sugarcane in South America. Leonotis nepetifolia has been found in the Tablelands Regional Council area.


Ligustrum lucidum - Large-leaved Privet, Tree Privet - Declared class 3

Ligustrum lucidum

Family: Oleaceae

Origin: Native to eastern Asia.

Naturalised distribution: This species in mainly naturalised in the wetter parts of eastern Australia.

Habitat: It is often cultivated as a hedge or windbreak, and has often become naturalised in rainforest areas.

Distinguishing features:

Habit: usually a small tree growing 4-12 m tall, but can grow to 25 m in height.

Stems and Leaves: The stems and leaves are glabrous and the younger stems are rounded and greenish in colour. Older stems and branches usually develop a relatively smooth greyish-coloured bark as they mature, which is loosely covered with lenticels. However, the fruit-bearing branches often turn orange or reddish in colour.

Reproduction and dispersal: This plant reproduces by prolific seed production, which are readily dispersed by fruit eating birds and other animals. May also be spread by water or dumped in garden waste.

Environmental impact: Broadleaf privet can invade relatively intact rainforest communities, and can outcompete riparian vegetation, and form dense thickets.

Other impacts: the leaves and fruit of this species are poisonous to livestock and humans. The pollen is a significant irritation to hay fever sufferers.

Local notes: Common along Lower Peterson Creek.

Control - stem injection with herbicide, or removal of entire plant.


Macfadyena unguis-cati - Cats Claw Creeper - Declared class 3

Macfadyena unguis-cati

Family: Bignoniaceae

Vine adventitious root climber and tendril climber.

Leaves compound, opposite; petioles 10-20 mm long; leaflets 2, entire or remotely toothed, 20-70 x 10-35 mm, glabrous; petioles 2-15 mm long; compound leaf tipped with 3 clawed tendrils.

Inflorescence: an axillary pair or a solitary flower.

Flower diameter 40-55mm; petals 5, yellow; calyx green, fragrant. September - October.

Fruit a capsule, brown or black, 150-470mm long x 8-10 mm wide; seeds several, brown winged at both ends, seed + wing, 20-40 mm long. January - June.

Distribution a native of Mexico, Argentina and Brazil.

Local notes: Not common but present along Priors Creek and at Yungaburra.

Control: two biocontrols available, cut and paint stems of larger plants with herbicide. This vine develops tubers which made it difficult to control before the introduction of the biocontrols.


Michelia champaca - Michelia

Michelia champaca

Family: Magnoliaceae

Origin: China

Form: tree

Flower colour; Mustard yellow

Description: This small tree , has alternate, lanceolate leaves to over 20 cm long that are slightly curved. The flowers are fragrant, a mustard yellow colour, and in each flower the ovaries are free from one another. The central stalk or receptacle elongates and bears the developing fruits along it. When fully developed each individual fruit is about 2.5 cm long, with a reddish tinge and whitish pustules; this follicle opens to release orange-red seeds.

Notes: Garden escape.

Local notes: Present in Malanda Falls Conservation Park, Lake Eacham section Crater Lakes NP, and surrounding areas.

Control: hand removal of seedlings, cut and paint stems of larger plants with herbicide.


Ochna serrulata - Mickey-Mouse Plant, Ochna

Ochna serrulata

Family: Ochnaceae.

Form: Shrub

Origin: Native of southern Africa.

Flowers/Seedhead: Flowers: Solitary on stalks 1-2 cm long; petals about 1 cm long, yellow, soon falling. Flowers spring to summer.

Description: Shrub to 3 m high. Leaves oblong to elliptic, 2-6 cm long, shiny, with toothed margins; leaf stalk almost absent to 1.3 cm long. Fruit round, green initially, ripening black, succulent on the red expanded part of the stalk where fruit attaches (receptacle) and surrounded by the bright red petal-like structures (sepals), 8 mm long, that are often mistaken as Ochna's flower. One seed in each fruit.

Distinguishing features: Distinguished by branches with raised corky areas (lenticels). Sepals green at first, becoming enlarged and red in fruit, turning down when fruit is mature.

Dispersal: Spread by seed.

Notes: Garden escape, often growing in bushland from dumped rubbish and bird-dispersed seed.

Local notes: Common around Yungaburra with some infestations along the Lower Peterson Ck.

Control - hand remove smaller plants, cut stump and paint with herbicide.


Ricinus communis - Castor oil plant

Family: Euphorbiaceae

Origin: and Asia.

Habit: A tall branching perennial shrub which grows to 3 m high. It has stout hollow branches which are a dull pale green or red; older branches and trunks turn greyish.

Flowers/ Seedhead: flowers are crowded in stout, erect spikes in the forks of the upper branches. Female flowers are in the upper part of the spikes, male flowers at the base. Female flowers develop into fruits about 2.5 cm across which are covered with soft green or red spines. These fruits have three segments, each segment containing one large, mottled, smooth seed. When ripe, the fruits explode violently and throw the seeds a distance of several metres.

Description: leaves (10 - 60 cm across) are widely spaced on the branches and grow on long, stout, hollow stalks attached off-centre to the bottom of the leaf. Each leaf is divided into 7 to 9 pointed triangular segments with toothed edges and conspicuous veins. Leaves are glossy, dark reddish-green when young, glossy green when mature.

Dispersal: ripe fruits explode violently and throw the seeds a distance of several metres. Seeds also spread by flood waters.

Impacts:

Local notes: Castor oil appears to be common in patches along the Barron River.

Control - hand removal of seedlings or small numbers of plants can be effective, basal bark or cut stump larger plants.


Rivina humilis - Coral Berry, Turkey Berry

Rivina humilis

Family: Phytolaccaceae

Origin: Native to southern USA, Mexico, Central America, the Caribbean and South America.

Naturalised Distribution: Widely naturalised in the coastal and sub-coastal districts of eastern Australia.

Habitat: This species prefers damp, shady sites and is a weed of closed forests, forest margins, riparian vegetation, disturbed sites, waste areas, urban bushland and gardens in tropical and sub-tropical regions.

Herb or shrub to 2m.

Leaves simple, entire or toothed, 40-120 x 15-40, upperside glabrous, underside with a few minute hairs along midrib and main veins, petioles 10-50 mm long.

Inflorescence a terminal or axillary raceme.

Flower petals absent, sepals 4, green, white or pink, 2-3mm long, March - August.

Reproduction and Dispersal: This species reproduces by seed, which are probably dispersed by water and in mud attached to animals and vehicles.

Local notes: Common as an understorey plant in Mabi forest.

Control - foliar spraying with herbicide.


More weeds

Weeds Why bother? - Declared and significant weeds in Queensland - Lantana - Local Law Declared weeds - Stevia ovata

Environmental Weeds - A - C - D - K - L - R (this page) - S - Z - Weed glossary