84 
Table 1 
The vegetation types mapped within the Tundra Biome study area, Prudhoe Bay, Alaska. 
For each type the characteristic species and microsites are given. 
Characteristic Species 
Most Common Types: 
1. Dryas integrifolia and crust lichens. Several other 
cushion dicotyledons and fruticose lichens. 
2. Dryas integrifolia and Cetraria spp. Several other 
fruticose lichens and sedges. Few or no crustose 
lichens. 
3. Carex aquatilis and/or Eriophorum angustifolium 
and Dryas integrifolia. Several other sedges and 
dwarf willows. Very few or no lichens. 
4. Carex aquatilis and/or Eriophorum angustifolium 
and Drepanocladus spp., usually with Pedicularis 
sudetica. No lichens. 
5. Carex aquatilis and Scorpidium  scorpioides. No 
lichens. 
6. Carex aquatilis and/or Arctophila fulva. No mosses 
or lichens. 
No vegetation. 
8. Saxifraga oppositifolia and Salix reticulata often 
with Juncus biglumis and several lichens. 
Snowbanks and Pingos: 
9. Cassiope tetragona and Salix rotundifolia. 
10. Diverse vegetation with Dryas _ integrifolia, 
Oxytropis nigrescens and Carex rupestris. Several 
lichens and mosses. 
Stream, River, and Lake Margins: 
11. Diverse vegetation with Salix rotundifolia, Chry- 
santhemum integrifolium and Oxyria digyna. 
12. Carex aquatilis and Dupontia fisheri with Saxifraga 
hirculus and other dicotyledons. 
13. Salix lanata and Carex aquatilis. Shrubby willows 
with a Type 12 understory. 
Characteristic Microsite 
Tops of high-centered polygons, small ridges and high 
creek bluffs. 
Dry polygon rims, and well drained areas. 
Polygon rims and flat areas that are not continually wet. 
Centers of many low-centered polygons, troughs and 
poorly drained areas, such as pond margins. 
Very wet areas where there is shallow standing water 
throughout the summer. Wet polygon troughs and pond 
margins. 
Standing water of moderate depth (30-100 cm). Lake 
margins and thermokarst pits. 
Deep water ( > 100 cm). 
Frost boils. 
Snowbanks. 
Pingos. 
Slumping river bluffs, areas of erosion and/or solifluc- 
tion. 
Stream banks. 
Stream and lake banks. 
