colickwort, field lady
Aphanes arvensis L. (Alchemilla arvensis Lamk.)
Parsley piert is a small native annual sometimes plentiful in cornfields on dry, loamy, calcareous soils. It occurs on soils within the pH range 4.0 to 7.5. It is common throughout the UK on arable land and bare patches in grassland. It occurs mainly as a winter annual.
There is evidence that parsley piert was a weed of crops in the Bronze Age. It occurs in winter wheat but is not commonly found in spring barley. Parsley piert seed was recorded frequently in seedbank surveys of arable soils in England and Scotland.
Parsley piert has medicinal uses and is an important remedy for dissolving kidney stones.
Parsley piert flowers from April to October. It is an apomictic species that can be found in flower and fruit for 7 months of the year. Seed is set from May onwards. The time from germination to fruiting is around 100 days.
Freshly shed seed requires a period of after-ripening and germination is delayed until at least the autumn. Seed germinates better at alternating temperatures in the light. In the field, the main period of seedling emergence is August to November but odd seedlings can emerge through to April. In a sandy loam soil, field seedlings emerged from the top 30 mm of soil with 89% in the upper 15 mm and 60% in the surface 5 mm.
Parsley piert seedlings are frost tolerant and overwintering plants form cushion-like tussocks.
Seed is reported to persist in soil for 3-5 years and can remain dormant for several years before emerging.
Viable seed has been found in cattle droppings.
Parsley piert is not normally a troublesome weed and surface cultivations will usually keep it down as will a dense crop stand. It is thought to increase in continuous cereals. In a comparison of different tillage regimes, parsley piert was favoured by reduced cultivations. Parsley piert appears to dislike lime.
Seed numbers were reduced by 50% after fallowing for a year. Fallowing every 5th year over a 15-year period did not maintain seed numbers at a low level. Lengthy seed dormancy and fresh seeding in the intervening cropped years nullified any benefits from the fallow periods.
Updated November 2007.