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Table of Contents
Foreword
Preface
Glossary

Chapter 3: Geologic Structure and Landforms

3.30: The Assiniboine River in Spruce Woods Provincial Park

As in Figure 3.29 the Assiniboine River has cut through sands into clays to produce optimum conditions for meandering. In this photo the river wanders from west to east through the sand hills of Spruce Woods Provincial Park. Also as in Figure 3.29 river cliffs are found on the outside of river bends 1 and sandy point bars on the inside 2. Meander scrolls are obvious both in wooded areas 3 and where land has been cleared for agriculture 4. Numerous cutoffs of various ages can be seen. An indistinct one 5 is probably the oldest; it is well removed from the river and is completely infilled. Several still contain some water 6 and are probably newer although they were already in existence when the original DLS map was compiled in 1909. Another cutoff 7 is much more recent; it was part of the main river channel in 1909. Now (1951) it is completely cut off and sediment has been deposited across the meander neck 8.

In the southeast a combination of spring sapping and slumping has produced a series of embayments 9, and both north and south of the river are water-eroded dry ravines 10. Stabilized sand dunes exist on both sides of the river, with one small patch of open sand 11.

Spruce Woods Provincial Park is unique in that “three major North American vegetation formations overlap: the grassland (or “prairie”), the boreal (northern coniferous) forest and the temperate (eastern deciduous) forest.”[i] On the photograph grassland 12; coniferous trees, probably white spruce (Picea glauca) identified by their dark tone and triangular shadow 13; and deciduous trees 14 are all visible. Yellow and light-brown leaves on the deciduous trees—mainly aspen (Populus tremuloides)—give some a light tone on this fall photograph.

A small area mainly on the floodplain has been cleared for agriculture 15. Only a few farm trails penetrate the area 16.

Figure 3.30: The Assiniboine River in Spruce Woods Provincial Park

Figure 3.30: The Assiniboine River in Spruce Woods Provincial Park

Figure 3.30

Vertical air photograph: 15577-20

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

Date: October 11, 1956

Scale: 1:37,900 (approx.)

Location: Townships 8 and 9, Ranges 12 and 13 WI

Map sheets: 1:250,000 62G Brandon 

1:50,000 62G/11 Glenboro

Notes

[i] Rogosin, A. “The Spruce Woods Sandhills” in Wested, Everitt, and Stadel, op. cit. 1996, 56-59.