Fumaria species - Fumitories
Fumitories are identified by their flowers, inflorescence and fruits. The colour of flower is unreliable as they may darken considerably when fertilised. Plants which grow in shade can be difficult to identify.
The flower has four petals.
• The upper one is the largest with a sac-like nectar producing spur at its base and at the apex there is a ridge or keel. The edges on the side of the keel can be deflected upwards to forms wings.
• The two inner, lateral petals are usually dark in colour and are fused at their tips.
• The lower petal is narrow, keeled at the tip and sometimes spathulate (shaped like a spoon).
The two sepals are at the side where the pedicel joins and are usually pale or coloured.
Things to notice in a fumitory.
• Measure the length of 2 or 3 of the most mature and largest flowers, ignoring the lower petal.
• Measure the length of the sepals from the base to the tip, including the teeth of these large, mature flowers. Note the shape.
• Note the colour of the upper petal and wings.
• Is the lower petal spathulate?
• Look at an inflorescence, is the raceme longer than the pedicel?
• Do the mature fruits have a neck, this is like a ring between the fruits and the pedicel.
Once you have this information then you can key them out. This is a plant group where you cannot play “snap” with a flower book. I would recommend Stace or BSBI Handbook 12 by Rosalind Murphy “Fumitories of Britain and Ireland”.