Horehound; White Horehound
Introduced shrub or perennial forb to 1m tall. Leaves aromatic when crushed, opposite each other, 1-7cm long, 8-45mm wide, flat, hairy, toothed or irregularly lobed, with rounded tips. Flowers white, 2-lipped, tubular, with five lobes, in dense whorls of more than 12 flowers at the bases of paired leaves. Noxious weed Wentworth Shire. Declared plant SA. Noxious weed Vic.
Description and photo in GM Cunningham, WE Mulham, PL Milthorpe and J H Leigh (1981 and later printings) Plants of Western New South Wales page 573
Weeds of Australia Biosecurity Queensland Edition description: http://keyserver.lucidcentral.org/weeds/data/03030800-0b07-490a-8d04-0605030c0f01/media/Html/Marrubium_vulgare.htm