56 
the textural class of the mineral soil. All digits or 
digit groups are offset by commas. 
The most extensive soil type found within 
the map area, and probably regionally as well, is 
a meadow tundra soil termed Histic Pergelic 
Cryaquept (map unit No. 3). These soils ordinar- 
ily occur in association with one or more of the 
other major soil types by virtue of their wide- 
spread occurrence in the depressed centers of 
polygons fitting the definitions of terrain-relief 
map units 3 or 4. The following profile is 
representative of this soil. 
Soil type: Histic Pergelic Cryaquept* 
Terrain-relief: Low-center polygons 
(No. 3), discontinuous 
rims. 
Portion of element: Center; low,<10 cm hum- 
mocks cover 10% of sur- 
face. 
Vegetation: Scorpidium scorpioides 
and other mosses; Carex 
spp. Eriophorum sp. and 
Salix sp. 
Slope: 0% 
Depth in cm: 
0-8 Greyish brown (10 YR 5/2**); 
organic; fiber content 20% com- 
posed of Carex spp. and S. scor- 
pioides,; considerable included car- 
bonate; roots abundant; boundary 
abrupt, smooth. Very dark grey- 
ish brown (10 YR 3/2) to dark 
greyish brown (10 YR 4/2): or- 
ganic loamy fine sand; fiber con- 
tent 30%; fibers break down with 
difficulty; roots common; carbon- 
ate reaction; boundary abrupt, 
smooth. 
8-20 Very dark greyish brown (10 YR 
3/2) loamy fine sand; medium and 
coarse fiber; fiber content 50%; 
fibers break down easily; carbon- 
ate reaction; roots common; 
boundary abrupt, smooth. 
* All classification assignments are tentative. 
** Refers to Munsell color charts. 
20-25 Very dark greyish brown (10 YR 
3/2) and very dark brown (10 YR 
2/2) organic fine sand; medium 
and coarse fibers; fiber content 
50%; fibers break down easily and 
nearly completely; carbonate re- 
action; weak platy structure; roots 
few; boundary abrupt, smooth. 
Very dark greyish brown (10 YR 
3/2) very fine sandy loam; very 
weak carbonate reaction; weak 
platy structure; frost. 
25-26.5 
These soils are normally alkaline throughout 
the profile, ranging between pH 7.0 and 8.0. 
Soils of this group occasionally may have very 
high sodium levels. August field moisture is near 
200% (oven dried basis—odb). The means of the 
few fluid transmission rates available for these 
soils indicate K = 10.2 cm hr! in the upper 10 
cm, decreasing to K = 8.4 cm hr! between 10 
and 20 cm. 
A soil very closely associated with the one 
just described is designated on Plate | as map 
unit 4. However, it is restricted in its distribu- 
tion to polygon center areas with standing water 
or to nonpatterned areas with standing water 
near ponds. There is not sufficient morphologi- 
cal reason within the confines of the National 
Soil Taxonomy to classify it differently from 
soil unit No. 3. The soils do differ, however, 
primarily in that those designated No. 4 may 
have organic horizons which are somewhat 
thicker and less decomposed than those of soil 
unit No. 3. August water tables seldom drop 
below the ground surface. Saturated hydraulic 
conductivities are usually somewhat higher in 
the No. 4 soils, due probably to increased 
porosity of the less decomposed and thicker 
organic horizon. 
Soils designated as unit No. 2 on Plate | 
occupy the raised polygon rims and are associat- 
ed especially with terrain-relief unit 3. These 
soils with slight morphologic variations can also 
be associated with any of the first 6 terrain-relief 
units. Because they occupy the drier (better- 
drained) sites, they are commonly associated 
with raised center polygons along eroding stream 
