ee A2 -- The basis of differentiation into this type was the prominence 
of cattail. The dividing line was arbitrarily assumed to be reached when 
cattail occupied 30 percent or more of the zone of emergent vegetation. 
Table ) shows the species of vegetation found in this type. In general, 
there was an increase in the occurrence of submerged aquatics particularly 
water milfoil (iyriophyl ium spp.). Lesser duckweed was less abundant than in 
the sedge-whitetop potholes, but star duckweed was still abundant. Wild barley 
was often prominent on the immediately adjacent prairie. These potholes varied 
considerably in character. Number 39 was merely a type Al pothole with cattail 
added. The shoreline cover was whitetop and sedge growing out to a depth of 
about 15 inches followed by a narrow strip of nearly open water followed by a 
ring of cattail about 6 yards wide growing in water up to 20 inches deep. Star 
duckweed was the most abundant submerged aquatic, and lesser duckweed was the 
next most abundant plant of the open water. This area had been lightly grazed 
in the spring and fall only. 
Table ). Vegetation found in cattail potholes. 

Occurrence Average Average 
Species (Percent of percentage of density 
potholes) vegetation zone 

Typha latifolia 100 5 It = III 
Lemna trisulca 100 Ls pal 
Carex spp. 100 16 Ir 
Eleocharis spp. - Juncus spp. 83 15 II 
Hordeum _jubatum 83 52 It 
Fluminea festucacea 83 20 II 
Lemna Minor 83 7 r- 
Myriophyllum spp. 67 30 ware 
Scirpus validus 50 \ I 
Potamogeton spp. 33 | 3 ea 
Green algae »ee ) Bsa II 
Scirpus paludosus 33 1 I 
Water moss 17 
Coratophy llum demersum 17 _ | ‘ 
Utricularia spp. 17 
Utricularia vulgaris 17 

