Erodium cicutarium is an annual, winter annual or biennial that is a pioneer on disturbed and arid sites. It can cause yield reductions of crops and the seed is very difficult to clean out of small seeded crops. Erodium cicutarium is considered a noxious weed as it crowds out or outcompetes crops and native plant species. Erodium cicutarium provides forage for rodents, desert tortoise, big game animals, livestock and also upland game birds and songbirds. Prevention may be the best method for controlling Erodium cicutarium, however, it may be impossible to actually prevent this species from colonising, or to eradicate it, once present. There are few known chemical control methods for Erodium cicutarium besides, general herbicide controls.
Erodium cicutarium is described as an annual, winter annual or biennial. It has a prostrate basal rosette and upright, often leafy flowering stalks. The stalks range from < 10cm to about 50cm high, and originate in the axils of the leaves. The leaves are divided into fine leaflets (or lobes) and are finely dissected, similar to those of a carrot. The flowers are about 1cm across, pink or lavender, and borne on stalks in clusters of 2-12. The sepals of the flowers are somewhat pointed and hairy. The fruiting structure (consisting of the seeds, persistent bristly styles, and central placental axis) is 2-5cm long and resembles a stork’s bill. At maturity, the developing fruit splits into 5 segments, each with a long, spirally twisting style with a seed attached at the base. The style twists hygroscopically, drilling the seed into the soil.
Agricultural areas, range/grasslands, ruderal/disturbed.
E. cicutarium besides being a pioneer on disturbed sites, is also a residual or secondary colonizer. Seedlings can either establish from on-site seed or from seed carried in by animals. In annual grassland communities, E. cicutarium a persistent ruderal can be intolerant of the mulch layer that builds up in some areas. E. cicutarium will tolerate partial shade, but vigor is reduced.E. cicutarium prefers dry, sandy soil, and is found in many perennial horticultural crops, turfgrass, and landscapes.” It also grows readily on soils of less sandy texture. It occurs in great abundance throughout arid parts of California, including the Mojave Desert, E. cicutarium was among the first invasive Eurasian plants to become naturalized in California.Weed surveys indicate that E. cicutarium has recently increased in distribution and abundance on cropland, especially in areas where conservation tillage has been adopted.
E. cicutarium has the potential to become a serious competitor of early planted spring crops on the Canadian prairies, it has been recognised as a
problem weed capable of causing economic losses in pasture and forage crops (such as Medicago sativa), and in arid wildlands. This is facilitated by its ability to emerge and thrive under cool to moderate temperatures.
The characteristics of E. cicutarium that make it such a problem weed: “E. cicutarium germinates and flowers early and continues to flower throughout the growing season, giving it a longer inductive time period than many later-maturing annual species; ” E. cicutarium is a fierce competitor, producing many seeds that germinate early, developing a deep tap root quickly, depleting soil water, and preventing sunlight from reaching seedlings of other species that germinate later and it may prevent establishment of perennial grasses by blocking access to light.
Increased density and biomass of E. cicutarium created in response to increased soil nitrogen may heighten competition for soil moisture, potentially decreasing density, biomass and diversity of native annual plants.
Native range: Africa, Asia, and Europe (USDA-GRIN, 2003).
Known introduced range: Australasia-Pacific, and North America, South America.
An integrated approach to the management of Erodium cicutarium is important, especially since herbicides for in-crop control of E. cicutarium are limited and control is often unsatisfactory. For details on management options, please see management information.