Yellow burrweed
Also known as amsinckia or fiddleneck because of the position of their flowers at the top of the stem, yellow burrweed is a significant weed of grain, poppies and other crops in New South Wales, Victoria, South Australia and Tasmania in particular. There are four naturalised species in Australia and they are a declared weeds in some States. Not only can yellow burrweed cause yield loss, but it can also taint flour and the fragments of the seed coat can discolour flour. In addition, seeds are poisonous to livestock as they cause liver damage.
Description:
Control:
Yellow burrweed spreads by seed only, so good hygiene is important to avoid the introduction of it into new areas. Amsinckia germinates over an extended period in autumn and winter so while it may be controlled with a knockdown prior to sowing, a post-emergent herbicide application may also be required.
References:
Department of Primary Industries, Parks, Water and Environment (2019), ‘Amsinckia Species’, http://agriculture.vic.gov.au/agriculture/pests-diseases-and-weeds/weeds/a-z-of-weeds/amsinckia
