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Table of Contents
Foreword
Preface
Glossary

Chapter 3: Geologic Structure and Landforms

3.99: Stabilized Dunes on the Assiniboine Delta Northwest of Holland

 

With the exception of two small areas in the northwest and southeast, virtually the whole area is covered by sand dunes developed on the Assiniboine Delta. In the northeast is a meander of the Assiniboine 1, with scars left at previous positions of the river 2. In the southeast is the Cypress River 3 deeply incised into the delta. Three steep-sided tributary valleys 4, 5, 6, join it. The only land cleared for agriculture is south of the Cypress River 7.

Virtually all the dunes are stabilized, with the exception of a patch of bare sand in the west 8. This dune complex has a steep, wooded northeastern slope 9. Several dune ridges can be seen 10 with a general west-northwest/east-southeast trend in response to the prevailing wind. The stabilized dunes are covered by: 1) grasses that are light toned with smooth texture 11; 2) deciduous trees, probably aspen (Populus tremuloides) 12 that are darker toned and have a mottled texture; and 3) patches of, and individual, coniferous trees, probably white spruce (Picea glauca) 13 that are dark-toned with a triangular shadow.

The Assiniboine Valley side and the Cypress Valley and tributary valleys are wooded. This is probably riverine gallery forest “dominated by cottonwood, Manitoba maple, green ash and willows.”[i] South of the Assiniboine are light-toned patches of trees 14, probably deciduous trees that had changed colour by the time this fall photo was taken. A dark-toned area north of the Cypress River 15 is marshy and probably covered by willow (Salix spp.) trees.

Figure 3.99: Stabilized Dunes on the Assiniboine Delta Northwest of Holland

Figure 3.99: Stabilized Dunes on the Assiniboine Delta Northwest of Holland

Figure 3.99

Vertical air photograph: A15577-15

Flight height: 20,000 feet a.s.l.; lens focal length: 153.09 mm

Date: October 11, 1956

Scale: 1:39,750 (approx.)

Location: Townships 7 and 8; Range 12 WI

Map sheets: 1:250,000 62G Brandon

1:50,000 62G/10 Treherne

62G/11 Glenboro

Notes

[i] Scott, op. cit., 1996, 46.