Fumaria officinalis L.
A native annual found on cultivated and wasteland throughout the UK. It is not recorded above 1,000 ft. Common fumitory is sometimes plentiful on light sandy, calcareous and loamy soils and chalk but is rarer on clay.
Common fumitory is a weed of arable and horticultural crops. It is also a common garden weed.
Common fumitory has medicinal and therapeutic uses. It has been used to treat skin conditions. The flowers have been used to make a yellow dye for wool.
Common fumitory flowers from May to October and is self-fertile. Seed numbers per plant range from 300 to 1,600 with an average of 800. It can be found in fruit for 6 months of the year.
Light does not stimulate seed germination. In the field, most seedlings emerge from September to June with the main flush from February to May and a smaller one in October-November. Seedlings that emerge in the autumn continue to grow through the winter, even at low temperatures.
In a sandy loam soil, field seedlings emerged from the top 90 mm of soil, with the majority of seedling from between 5 and 60 mm. Very few seedlings came from the surface 5 mm of soil.
Seed mixed with soil and left undisturbed had declined by 70% after 6 years. In cultivated soil the loss was 90%. Seeds broadcast onto the soil surface, ploughed to 20 cm and followed over a 6-year period of cropping with winter or spring wheat had a mean annual decline rate of 21%. The estimated time to 95% decline was 10-21 years. Under a grass sward common fumitory had a mean annual decline of 1% and a half-life of over 20 years. Seed recovered from excavations and dated in excess of 25 years is reported to have germinated.
Fumitory seeds have been found as a contaminant in cereal and clover seed. Seed is found in cattle droppings and may be transported by ants.
Control is by repeated surface cultivations in spring and early summer, and by the inclusion of root crops in the rotation.
In winter cereals, common fumitory is favoured by ploughing and other deep cultivations, and discouraged by minimal tillage systems.
Fumitory is eaten by cattle and sheep but horses avoid it. Goats dislike it when the plant is fully grown.
Updated October 2007.