Linseed (Flax)
Medium Risk
Latin Name: Linum usitatissimum
Linseed is also known as flax. It is a slender, erect, annual plant which grows single stems. The leaves have three veins and are 1.5mm to 3mm wide. The flowers are pale blue and normally have 5 broad petals, although four petals are somertimes found. Linseed (flax) flowers June - August. The flowers are followed by fruit capsules. Linseed (flax can) be found growingin dry permanent grassland. There are over 200 species.
Symptoms can include:
Salivation, staggering, dilated pupils, rapid pulse, gasping, inability to stand and convulsions. In some cases it has been reported that no symptoms were seen before death.

Linseed can be fed to horses as the poisons it contains (prussic acid) is destroyed by heat. It must therefore be thoroughly cooked before feeding. To have any real effect large quanities of the natural seed must be eaten.