Quick Facts

Quick facts

  • Hairy Thornapple (Datura wrightii) is an annual or short-lived perennial shrub that grows to 1 m high and has white tubular flowers.
  • It is found widely in subtropical to temperate areas of Australia.
  • It is toxic to stock and people.
  • It is spread by seeds particularly as a contaminant of crop seed, in mud on vehicles and by water.
  • It is mainly found amongst crops and in other highly disturbed sites.

What Does It Look Like?

What is it?

Hairy Thornapple (Datura wrightii) is a much-branched,  bushy annual or short-lived perennial herb that grows to 1 m high. The stems are dull greyish green and covered mainly in persistent, backwards -pointing, non-glandular hairs but also with some erect glandular hairs, making it slightly clammy to touch, especially the new growth. The leaves are alternately arranged along the stem, stalked, dull greyish green with mostly non-glandular hairs pointing towards the leaf base and fewer, erect, glandular hairs, oval in outline (widest below the middle), mostly 50–100 mm long and 40–60 mm wide, sometimes up to 160 x100 mm, with a few short, broad, angular or rounded lobes on the margins toward the base.

The flowers are borne singly in the branch forks and are shortly stalked. They are 140–200 mm long, white, usually tinged greyish lavender or greyish pink towards the top, trumpet-shaped, with 5 short, broad lobes each ending in a narrow tip (overall appearance 5-lobed). There is a tubular, dull-green calyx (outer covering) extending for slightly less than half the total flower length from the base; it is smoothly rounded and has 3–6 teeth, often of uneven length.

Hairy Thornapple has capsular, prickly fruits that are bent over or hang downwards on the plant. At maturity the capsule body is globular or almost so, usually 25–35 mm in diameter and covered in numerous slender prickles all more or less equal in length and mostly 3–5 mm long, sometimes up tp 10mm long. The capsules break up unevenly, shedding a large number of seeds, or sometimes begin to open into 2–4 segments, before soon breaking into uneven fragments. The seeds are D-shaped, finely pitted, with a smooth, deep furrow along the margins, yellow-brown to grey-brown, 5–6 mm long ( Haegi 1976; Purdie et al. 1982).

Because Hairy Thornapple is very similar to Downy Thornapple (Datura innoxia) it has been suggested that they are the same species ( Nee 1993), but this is erroneous and detailed studies have provided ample evidence that they are quite separate species (Haegi 1976; Bye & Sosa 2013).

For further information or assistance with the identification of Hairy Thornapple contact the herbarium in your state or territory.

Flower colour

White, usually tinged greyish lavender or greyish-pink

Growth form (weed type/habit)

Much-branched, robust, bushy herb with short-lived perennial root system and annual aerial parts 

Where it currently grows? Preferred habitat

Hairy Thornapple is sporadically naturalised mainly in south-eastern Australia, usually in fertile soils close to habitation, where moisture is available.

Are there similar species?

Because of its large flowers, dull greyish green foliage and nodding capsules, Hairy Thornapple is most similar to Downy Thornapple (Datura innoxia), but that species differs in having only erect, glandular (sticky) hairs on the stems and leaves, as well as flowers that are pure white. Hairy Thornapple has mainly backwards-facing non-glandular hairs (with only a few erect sticky ones) and flowers that are usually tinged greyish lavender or greyish pink towards the tips. Common Thornapple (D. stramonium) and Fierce Thornapple (D. ferox) do not have the velvety hair covering found  on the stems and leaves of Hairy Thornapple Thornapple and also both have erect (not nodding) capsules (Haegi 1976; Purdie et al. 1982).

Why Is It A Weed?

What are its impacts?

Agriculture: Hairy Thornapple is only sparingly naturalized. Its occurrence is closely associated with human habitation because of its cultivation as an ornamental; it is found, for example, persisting in derelict gardens, as a localised escape or in intermittent populations established from garden spoil. Although, as in the other species of Datura all parts are toxic to stock because of the presence of tropane alkaloids, there are few records of poisoning reliably attributed to Hairy Thornapple.  In this case the roots as well as the seeds are particularly poisonous. 

Human impacts: Although all parts are toxic, there are few substantiated records of poisoning of humans.

How does it spread?

Hairy Thornapple is dispersed by seed in water runoff, when soil is transported or by humans because it is grown as an ornamental garden plant. Dispersal through root fragments, intentional or otherwise, also occurs. 

What is its history in Australia?

The earliest records of Hairy Thornapple in Australia are at Melrose in South Australia (1891), Ross in Tasmania (1896) and Adelaide (1907).  Self-sustaining populations have almost certainly become established as garden escapes in the first instance, probably on multiple occasions. (Haegi 1976; AVH 2021).

How To Manage It?

Best practice management

Non-chemical control: Mechanical removal of Hairy Thornapple plants is feasible for the usually small infestations. 

Chemical control: as in other species of Datura, small plants are susceptible to herbicide, but this form of control may be ineffective for mature plants (Parsons & Cuthbertson 2001).

Please see the Australian Pesticides and Veterinary Medicines Authority for chemical information http://www.apvma.gov.au 

Does it have a biological control agent?


When does it grow? (lifecycle/growth calendar)

Hairy Thornapple is a bushy herb with a short-lived perennial root system and usually aerial parts. Flowers may be produced when the plant is only 2-5 weeks old. It flowers and fruits throughout the summer and autumn, but the aerial parts usually die off and are sometimes killed by frosts winter. In summer the plants usually regrow from the semi-perennial root system for several seasons, while in more protected sites the plants may persist through winter.

Where Is It Found?

Which states and territories is it found?


What areas within states and territories is it found?

Hairy Thornapple is naturalized (as scattered occurrences) principally in settled and agricultural areas south of 31 degrees Latitude in South Australia, Victoria and New South Wales. There are also a few records from  south-west and north-west Western Australia and one each from the Northern Territory (Alice Springs) and central Tasmania (AVH 2021).

Where does it originate?

Hairy Thornapple is  native to the south-western United States of America and adjacent parts of Mexico ( Nee 1993; GRIN 2008).

National And State Weed Listings

Is it a Weed of National Significance (WONS)?


Where is it a declared weed?


Government weed strategies and lists – Weeds Australia

Is it on the National Alert List for Environmental Weeds?


Government weed strategies and lists – Weeds Australia

Is it on the Agricultural Sleeper List?


Government weed strategies and lists – Weeds Australia

Names And Taxonomy

Main scientific name

Datura wrightii

Other scientific names (synonyms)?

  • Datura metel L. (misapplied by Black, J.M. 1957, Flora of South Australia Edn 2. 4: 755., p.p.)
  • Datura meteloides DC. ex Dunal (misapplied by Everist, S.L. 1974, Poisonous Plants of Australia. 633.)

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