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).
