96 
EQUISETACEAE 
Equisetum arvense L. Common Horsetail. 
Common in woods and thickets throughout the area, occupying a great 
variety of habitats. Fertile stems observed June 18 in the gorge of Little 
Buffalo river, and June 20 in Pine Lake district. 
Along Quatre Fourches river, No. 45; 30th base line district, Slave 
river, Nos. 55, 58, 62, 66; Government Hay Camp district, Slave river, 
Nos. 1481, 1488; Fort Smith, No. 63; Pine Lake district, Nos. 1482, 1489, 
1490; Peace point, No. 1480; sink-hole 16 miles east of Moose lake, No. 
1483, Moose (Eight) Lake district, Nos. 1484, 1485, 1486, 1487. 
E. pratense Ehrh, Goosegrass. 
Abundant in the poplar and poplar-spruce woods on river flood-plains 
throughout the area. In such situations along Slave and lower Peace rivers 
it forms a dense cover on the forest floor. In its early, succulent stages it 
is eaten with apparent relish by grazing horses. Observed in fruit June 
9 to 20. 
Along Quatre Fourches river, No. 45; 30th base line district, Slave 
river, Nos. 44, 47; Government Hay Camp district, Slave river, No. 1497; 
Fort Smith, No. 43; Pine Lake district, No. 1493; near Hound lake, about 
18 miles south of Pine lake, No. 1494; Peace point, No. 1495; Moose 
(Eight) Lake district, Nos. 1496, 1498; base of eastern slope of Caribou 
mountains, No. 1492. 
E. sylvaticum L., var. paueiramosum Milde. See Rhod. xx, 129 (1918). Woodland 
Horsetail. 
Common in rich spruce woods on the uplands, and in semi-open prairies 
at the base of Caribou mountains. Not collected in the lowland forests. 
Fruiting cones nearly all gone by the last week in June. 
Moose (Eight) Lake district, No. 1462; base of eastern slope of 
Caribou mountains, Nos. 1457, 1459, 1460; eastern edge of Caribou Moun- 
tain plateau. No. 1458. 
E. palustre L. Marsh Horsetail. 
Common on very low mud bars along the rivers, where it has a trailing 
habit and colonizes areas that are submerged in flood times. Observed 
in fruit in late June and early August. 
Government Hay Camp district, Slave river, No. 1470; lower Slave 
river, No. 40. 
E. limosum L. E. fluviatile L. See Rhod, xxiii, 43 01921). Swamp Horsetail. 
Abundant on the slough margins of lakes and ponds, and on the muddy 
shores of river flood-plains. Fruiting cones observed in late June and the 
first half of July. 
Lower delta of Athabaska river, No, 33; east shore of lake Mamawi, 
No. 1473; Government Hay Camp district, Slave river, Nos. 1478, 1479; 
Fort Smith, No. 31; Pine Lake district, No. 1477; sink-hole 16 miles east 
of Moose lake, No. 1471; Moose (Eight) Lake district, Nos. 1475, 1476; 
Indian graveyard, Peace river, No. 1472; lower Slave river, Nos. 25, 26. 
