Distribution
Albania, Andorra, Armenia, Australia, Austria, Azerbaijan, Belarus, Belgium, Bosnia and Herzegovina, Bulgaria, Canada, China, Croatia, Czech Republic, Denmark, Estonia, Faroe Islands, Finland, France, Georgia, Germany, Hungary, Iceland, Ireland, Italy, Jan Mayen, Japan, Kazakhstan, Kosovo, Latvia, Liechtenstein, Lithuania, Luxembourg, Madagascar, Malta, Mongolia, Montenegro, Netherlands, North Korea, North Macedonia, Norway, Poland, Romania, Russian Federation, Serbia, Slovakia, Slovenia, South Korea, Spain, St. Pierre and Miquelon, Sweden, Switzerland, Turkey, Ukraine, United States of America

Native to: Alaska, Albania, Alberta, Altay, Austria, Baltic States, Belarus, Belgium, British Columbia, Bulgaria, Buryatiya, Central European Rus, Chita, Connecticut, Czechoslovakia, Denmark, East European Russia, Finland, France, Føroyar, Germany, Great Britain, Hungary, Iceland, Ireland, Irkutsk, Italy, Japan, Kamchatka, Kazakhstan, Khabarovsk, Korea, Krasnoyarsk, Kuril Is., Labrador, Madagascar, Maine, Manchuria, Manitoba, Masachusettes, Michigan, Minnesota, Mongolia, Netherlands, New Brunswick, New Hampshire, New York, Newfoundland, North European Russi, Northwest European R, Northwest Territorie, Norway, Nova Scotia, Nunavut, Ontario, Poland, Primorye, Québec, Romania, Réunion, Sakhalin, Saskatchewan, Sicilia, Spain, Svalbard, Sweden, Switzerland, Tasmania, Turkey, Tuva, Ukraine, Vermont, Victoria, West Siberia, Wisconsin, Xinjiang, Yakutskiya, Yugoslavia, Yukon.

Shoots erect, indeterminate, 8-12 cm, becoming short-decumbent; leaves of mature portion slightly smaller than leaves of juvenile portion (more pronounced in sun form); indistinct annual constrictions present (more pronounced in shade form); juvenile growth erect. Leaves spreading-ascending (shade) to appressed-ascending (sun) in mature portion, more reflexed in juvenile portion, green (shade) to yellow-green (sun), lustrous; largest leaves triangular, widest at base, 4-7.5 mm; smallest leaves lanceolate, 3.5-5 mm; margins almost entire, papillate; stomates on both surfaces, numerous on adaxial surface, 30-90 per 1/2 leaf. Gemmiferous branchlets produced in 1 pseudowhorl at end of annual growth; gemmae 4-5 × 3-4.5 mm, lateral leaves 1.5-2 mm wide, broadly acute. Spores 29-37 µm. 2n = 268.
Habitat: Terrestrial in sandy borrow pits, ditches, lakeshore swales, and conifer swamps, rarely on acidic, igneous rock or calcareous coast cliffs.
Elevation: 0-700 m, rarely to 1600 m.
(Flora of North America)

Багаторічна вічнозелена трав’яна рослина 5-20 см заввишки. Стебло висхідне, рівнодихотомічно розгалужене, по мірі наростання біля основи полягає і вкорінюється, формуючи куртинки до 1,5 м в діаметрі. Стебло густо вкрите лінійно-ланцетними філоїдами, у 8 вертикальних рядах. Спорангії у пазухах філоїдів. Спори дозрівають у серпні-вересні, спороношення закінчується навесні наступного року.
Вегетативне розмноження вкоріненням полеглої частини стебла і за допомогою виводкових бруньок.
(ЧКУ, 2009)