MICHIGAN ACADEMY OF SCIENCE. 
81 
SECONDARY SPECIES. 
Panicum xanthophysum. 
Danthonia sp icata . 
Anaphulis margaritacea. 
Gnaphalium decurrcns. 
Lactuca canadensis. 
Aralia hispida. 
8 ol Ida go canaden sis. 
Pa n icun i d cp auperatum. 
Aster azure us. 
Poa pratensis (usually scattering 
but sometimes forming a light 
sod) . 
Agrop ijrum repen s. 
Agropyrum repens f. glaucum. 
Apocynum androsaemifoliuni. 
Cyperus spp. 
Cy perns rivutaris. 
Agro sti s h iema li s . 
Agrostis alba * 
Carex umbellata. 
Carex festucacea. 
Asclepias syriaca. 
A sclepias p hyt o I accoi des. 
Erigeron ramosus. 
Lycopodium complanatnin. 
E icraciu in renosuin. 
Hieracmm scabru in . 
Aster la e vis. 
C o i wo l vulus spithamaeus. 
Viola arenaria (rare). 
Ara b is glab ra . 
M el a in pyrum linear e. 
Aristida sp. 
P° hjg° nu m cilinode. 
Cirsium arvense. 
Fra gar ia virginiana. 
Vcrbascum thapsus. 
Rumex acetosella* 
8 mi la cina si el hit a . 
Phleum pretense * 
Lepidium apetalum* 
Lepidium Virginia, mini * 
Apo cynum cann a b inn in. 
Cladonia rangiferina. 
Antennaria spp. 
Physalis grandi .flora (Loew). 
Lycopodium tristachyum . 
Solidago hispida. 
*An asterisk indicates species which are ubiquitous. 
RELIC SPECIES. 
Pedicularis canadensis. Osmunda cinnamomca. 
Epilobnum angustifolium. Smilacina racemosa. 
Erigeron canadensis. Monotropa uniflora. 
8milacina Irifiolia (in tree-re- 
mains after fire) . 
summary. 
1. The Douglas Lake region is an area of low, sandy ground in the 
middle western part of Cheboygan county and the middle eastern par 
of Emmet county, Michigan. This report is based on that part of the 
area within five to eight miles in all directions from Douglas Lake. 
2. The region lies within the transition belt between the north- 
eastern conifer and the deciduous forest provinces, within an area of 
little competition between them, in a climate favorable to tree growth. 
3. The region has been repeatedly glaciated. The surface soil is 
sandy virtually thruout except for the clayey area northwest of Burt 
Lake. 
4. The region contains 32 plant associations, representing two plant 
provinces; the northeastern conifer and the deciduous forest. 
5. A study of the successions between the different plant associations 
leads to a very satisfactory understanding of the plant dynamics. 
r-h 
