EXPERIMENT STATION BULLETINS. 395 



Twisted Willow Grass, Draba incana arabisans. S. Wats. 



Range: Along the Great Lakes. 

 Wild Lupine, Lupinus perennis L. 



Range: Sandy soils generally over Lake Region. 



I arvense L. 

 The Clovers — Trifolium •] pratense L. 



f repens L. 

 Rigid Tick Trefoil, Meibomia ridida (Ell.) Kuntze. 



Range : Dry soils of Michigan. 

 Narrow Leaf Bush Clover, Lespedezia augustifolia (Pursh) Ell. 



Range: Dry soils of Michigan. 

 Beach Pea, Lathyrus maritimus (L.) Bigel. 



Range : A perrenial decumbent pea vine of great value on the Great 

 Lake Region. It is perfectly hardy and a good spreader. 

 Sand Violet, Viola subvestita Green. 



Range: Throughout Lake Region. Several other members of this 

 genus do well in a partial shade or dry or sandy soils, and 

 should be encouraged. 

 Fire Weed, Chamaenerion augustifolium (L.) Scop. 



Range : Dry soils and comes in readily after clearing and fire. Com- 

 mon over the Lake Region. 

 Oakes' Evening Primroi^e, Oenothera Oakesiana Robbius. 



Range : Common along the Great Lakes. 

 Large Purple Gerardia, Agalinis purpurea (L) Britton. 



Range: Common on low lying flats along the shores of the Great 

 Lakes but not on the drift sands. 

 Twin Flower, Linnaea americana Forbes. 



Range : On north slopes and cool cover. Not on sands unless shaded 

 and moist. 

 Beach Cocklebur, Xanthium echinatum Murr. 



Range: A coarse sand weed, growing along lake shores and rivers. 

 WTiite Aster, Frost Weed. Aster ericoides L. 



Range: On dry soils of Michigan. 

 Lake Huron Tansy, Tanacetum huronense Nutt. 



Range : On sand dunes of north part of the Southern Peninsula, and 

 north, 

 Canada Wormwood, Artemisia canadensis Michx. 



Range: A perennial root plant growing on sand dunes from New 



Buffalo to Mackinac City. 



Only a small number of plants, grasses and trees of this list form 



active, aggressive, advance agents of natural reclamation. The rest 



establish themselves gradually and onl}^ after some little protection is 



afforded by the advance growth. 



COVER TYPES. 



There are two distinct forms or types of cover to deal with before a 

 final forest cover is established. The first is a temporary type and in- 

 cludes all those hardy persistent aggressive plants above listed. The 

 most prominent being the beach grass, or Marram, the sand pea, the wil- 

 lows, poplars and sand cherries with often a sprinkling of paper birch. 

 These form the temporary type which establishes a crust on the sand 



