- Name also: Silvery Cinquefoil, Hoary Cinquefoil
- Family: Rose Family – Rosaceae
- Growing form: Biennial or perennial herb.
- Height: 20–50 cm (8–20 in.). Stem limp–ascending–erect, branched, hairy, reddish at least at base.
- Flower: Corolla regular (actinomorphic), yellow, approx. 1 cm (0.4 in.) broad; petals 5, with shallowly notched tips, 4–5 mm (0.16–0.2 in.) long, slightly longer than calyx lobes. Calyx 5-lobed; with epicalyx, epicalyx lobes narrow, same length as calyx lobes. Stamens 20. Gynoecium separate, pistils many. Inflorescence a corymb.
- Leaves: Alternate (often also basal rosette, sometimes overwintering), basal leaves long-stalked, stem leaves short-stalked–stalkless, stipulate. Blade palmate, with 3 leaflets, leaflets quite narrow, narrow-based, lobed–large-toothed, with revolute margins, dark green on top, underside densely white-haired, sometimes also hairy on top. Stipules entire–lobed.
- Fruit: Quite round, yellowish, matt achene, many together.
- Habitat: Meadows, rocks, lawns, banks, roadsides, wasteland.
- Flowering time: June–August.
Silver cinquefoil is very diverse. The reason for this diversity is at least partly due to the plant’s ability to produce seeds apomictically, without being fertilized. Different stands remain separate and even small mutations are faithfully reproduced, giving rise to micro-species. For example, the amount of silver-gray tomentums (woolly hairs) can vary within the same garden. Micro-species of silverweed are nowadays usually regarded as subspecies or variations, the most common of which in Finland is probably var. incanescens (earlier Potentilla neglecta). Other silver cinquefoils are at least var. argentea, var. demissa, var. decora, var. dissecta and var. acutifida. Although pollination is not necessary for silver cinquefoils, its seeds do not develop if they have not been fertilized, and the seed will not develop properly without a visit from a pollinator. Many kinds of insects are able to pollinate silverweed’s saucer-like open flowers.
Silver cinquefoil in the wild grows on rocky precipices. People have helped it spread and become more abundant by creating gaps in nature because the species is happy to move into culturally influenced places. It grows commonly in dry yards, beside streets and roads, on railway embankments and waste ground and in open sandy areas. In central and southern Finland it is more common. Stands in northern Finland are around Oulu and Kuusamo, and it is practically non-existent in Lapland.
Distinguishing silver cinquefoil variations from each other is not always easy. They can usually be easily distinguished from other members of the large genus by its short, shiny tomentums, which cover the undersides of the leaves. The Latin name argenteus means ’silver’ and is referred to in the species’ scientific name. The surface of the leaflets is usually matt dark green, but an especially ornamental form is shiny silver all over.
Potentilla tergemina (earlier Potentilla multifida)
NOT TRANSLATED YET. Meillä Suomessa erittäin harvinaisena tavattavan sulkahanhikin (aiemmin nimellä liuskahanhikki) saattaa sekoittaa hopeahanhikin liuskalehtiseen muunnokseen, liuskahopeahanhikkiin, koska molemmilla on hyvin liuskaiset lehdet. Liuskoja analysoimalla ero kuitenkin on melko selkeä; hopeahanhikkien lehdet ovat sormiliuskaisia (eli kaikki liuskat lähtevät yhdestä pisteestä) sulkahanhikin lehdet ovat yleensä 2- tai 3-parisia ja päätölehdykkäisiä (voivat kuitenkin joskus näyttää 5- tai 7-sormisilta).