Kerria japonica

[8][9] Since 2014 the UK's Royal Horticultural Society has been receiving reports from gardeners and horticulturalists of damage to plants of the shrub Kerria japonica.

This highly contagious disease, known in English as kerria twig and leaf blight, was known in the U.S. but has not previously been observed on British plants.

[11][12] The leaves and roots contain 0.002% Hydrogen cyanide, while the tender shoots are a rich source of Vitamin C (200 mg/100g) and the seeds contain 44.9% protein and 45.3% fat.

[12] The flower petals contain the O-methylated flavonoid pectolinarin, (5,7-dihydroxy-4,6-dimethoxyflavone-7-rutinoside), a cytotoxic compound known also as Neolinarin and found also in Linaria spp., Kickxia elatine and the Duranta species D.

[13] Kerria japonica is mentioned frequently in the Man'yōshū, the oldest extant collection of Japanese poetry from the AD first millennium.

Qing Dynasty poet Chen Hao (陳淏) celebrated the beauty of Kerria japonica in his agricultural treatise the Flower Mirror [ja; zh] (花鏡).

Kerria japonica by Abraham Jacobus Wendel , 1868