Hypochoeris radicata
flat weed (Aus)
Perennial rosette-forming plant with a tap root. Leaves all basal, oblanceolate, toothed, c 25 x 100mm, covered with stiff hairs. Flowers yellow, dandelion-like c 25mm diameter on branched stalks which produce milk when broken. Involucral bracts have a row of hairs up the middle. Seeds attached to fluff for wind dispersion.
There are many dandelion-like plants, including NZ dandelion, hawkbits and hawksbeards. In Britain and S. America where they come from, there are hundreds of very similar species / subspp, which may interbreed. Only 3 spp. of catsear recognised in NZ, including smooth catsear. This diversity may have implications for the amount of toxin present.
Common in rough pasture and waste ground throughout NZ.
Unknown.
Possible association with 'Australian' stringhalt in horses. 10kg/day for 50days has produced disease on a farm (in Brazil) where stringhalt had occurred, but catsear from a neighbouring farm had no effect.
Stringhalt, laryngeal paralysis.
Peripheral neuropathy.
Clinical signs, EMG.
Trauma, CNS disease.
Phenytoin has been used with partial success.
Good if treated.
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