22 lil.KM I.VN(.i;. M.-X. Kl. 



otluTwise it is one of the most frequent liilniis in our cfjuntrw (Jut of 

 l'"(iinosc;iii(li;i .ind Kii^si.i it has only been recorded as a great rarity at a 

 lew Central I'JnDpcan stations. 



No lichen is nuu-e widespread in our subalpine fir fPiiitts silvestrr) 

 forests than Chuionid alpesfris, our most valuable lichen h'om an economic 

 standpoint. It forms large 'pastures' several hundreds of metre higher as 

 well as lower than the upper tree line. It is, however, not a real high 

 alpine plant, and in the lowlands it is less common. It is often lacking 

 or rare on the coast itself. In the British IsKs it is rare, and in Central 

 Europe it is a mountain plant, or replaced by the related species Cladonia 

 portcutosn. 



We ha\e chiefly dwelt upon the eastern subalpine plants, which are 

 the most remarkable from a geographical point of \ievv. Otherwise the 

 group 'subalpine' plants will to a certain extent be a term, comprising a 

 great part of our common lichens, that are neither alpine nor lowland 

 species. Many of them are common also in Western Norway, and several 

 of them are wideh' distributed in temperate European countries. 



3. Alpine lichens. 



Alpine and subalpine lichens are more difficult of distinction than alpine 

 and subalpine phanerogamous plants. 



The lichens are not so sensitive to the unprotected conditions of lite 

 on the mountains, being more dependent on light and the competition with 

 other and stronger plants. If Pinus silvestcr forms the upper forest line 

 there is sufficient light for the lichens and there is little difference between 

 the lichen fields on either side of this line. Otherwise in the dark Picea 

 cxcclsa forest, the ground is covered with mosses and other plants, but 

 not with lichens. Bctiila odorata is the mother of a good soil which can 

 support a more exacting vegetation than the lichens. Lichen associations 

 are not rare in the Bctula odorafa forest, but phanerogamic associations 

 are more common. 



The slow growth of the lichens and their modest claims to life enable 

 them to live in meagre circumstances, at places which are too poor for 

 other plants and this notwithstanding the elevation above the sea, if their 

 distribution is not limited by climatic factors, such as winter temperature. 

 I am unable to give statistical data, but I am under the impression that a 

 relatively larger number of mountain lichens ha\'e a greater vertical range 

 than corresponding phanerogamous plants. 



In the first place many crustaceous lichens are alpine- such as Lccidca 

 arctogeiia on rocks, and Lccidca assiiiiilafa on earth. Species that are 

 alpine in Southern Norway often extend to the level of the sea in Northern 

 Norway if found there, e. g. Lccidca aglaca, Rliizocarpo)i alpicola, and 



