Characteristics | Geology & Landscape Development | Climate Fresh Water | Soils | Plants | Animals | Cultural Environment Topics & Habitats

Regional Characteristics
These uplands experience more severe winters, greater precipitation, and shorter growing seasons than the surrounding lowlands, but climatic conditions are not as harsh as in the Cape Breton highlands. The climate of this Region is reflected in the dominant hardwood vegetation characterized by a Sugar Maple, Yellow Birch-Fir association.

Bornish Hill Click to enlarge

Six of the eight plateaus (District 310) which compose the Region are sharply defined, with level plateau surfaces at elevations between 100 and 300 m above sea level. Margins of the plateaus generally fall abruptly, 100 m or more, with little dissection by stream valleys. The remaining two uplands (District 330) are at lower elevations and have a less severe climate and a greater proportion of softwood trees. Mainland parts of this Region are bordered by ancient sedimentary rocks on which soils are deeper and river valleys more deeply carved (District 320). All of these uplands provide excellent moose ranges.

Geology and Landscape Development
The blocks are made up of very resistant metamorphic and igneous rocks, among which are some of the most ancient rocks in Nova Scotia. In most cases, the blocks are bounded and crosscut by faults. At the margins these give steep scarp slopes; within the blocks, where harder and softer strata are juxtaposed, they produce rugged hills and valleys.

The crests of the blocks are often narrow and dissected but are usually uniform in height along their length. Their height relationship is cited as evidence for a Cretaceous planation surface. The crests progressively decrease in elevation southeastwards as they intersect an almost uniform surface now dissected and tilted to the southeast. Subsequent erosion has removed soft strata and left the resistant blocks as uplands. The prominence of the blocks varies according to the hardness of the adjacent rocks and their position on the tilted peneplain.

Climate
Elevation is the dominant influence on the climate of this somewhat diverse Region. The climate in different areas is modified by proximity to water masses. The main climatic features are wide daily and seasonal temperature rangers, and high precipitation, especially snowfall.

Winters are generally long and cold. Because of their greater elevation, the Cobequids record the coldest temperatures within the Region. The uplands south and east of the Bras d'Or Lake are slightly warmer than the rest of the Region because of lower elevations and the moderating influence of the Bras d'Or Lake and the Atlantic Ocean. Spring is late, although somewhat earlier in the Bras d'Or area. Mean temperatures do not rise above 0°C until April. Summer temperatures are cool at the higher elevations, but warmer towards Cape Breton. Freezing temperatures return before the end of November in the Cobequid Hills and Antigonish Highlands, and one or two weeks later in Cape Breton.

Total annual precipitation exceeds 1200 mm in the mainland. The Region is noticeably wetter in Cape Breton, where precipitation exceeds 1400 mm. Snowfall is greatest on the highest parts of the Mainland, exceeding 300 cm. In Cape Breton, 200-250 cm falls close to the Bras d'Or Lake, and over 250 cm elsewhere. The snow-cover season follows the same pattern, being longer in the mainland areas (more than 140 days) and somewhat shorter (130 days) in the rest of the Region. In midwinter, snow accumulations of more than 40 cm occur in the Cobequid Hills and Antigonish Highlands.

Cloud cover occurs frequently, and the relative humidity is high. Exposure to wind is an important factor at the highest elevations and in areas close to the Gulf of St. Lawrence.

The main features of the bioclimate of the Avalon Uplands are the short frost-free period, the short growing season, cool moist summers, and low evapotranspiration.

Fresh Water
There are relatively few lakes across this Region, but there are many rivers and streams. Most uplands in this Region tend to function as drainage divides for watershed areas. The headwaters are not especially productive.

Soils
The main influences on soils in this Region are the high precipitation, the presence of somewhat more basic igneous rocks, steep terrain that provides good drainage, and a prevalence of deciduous trees. Soils here are strongly leached but in many areas have higher natural fertility than soils found on the more acid upland rock. Soils are usually well-drained, shallow, and stony sandy loams, often of the Ferro-Humic Podzol Great Group. Because of low evapotranspiration, substantial levels of organic matter accumulate in the upper layers. Leaf litter from the hardwood forests develops into a mull or moder humus form.

C.D. Howe made the following observations on soil-forest relationships in 1912: "The felsites and syenites are similar to granites ... they vary in hardness, and the softer forms give rise to very vigorous soils which rank with alluvial soils in fertility, while the harder forms results in a soil similar in fertility to that of the more compact sandstones. They are, therefore, feeble soils."

The more recent Cumberland County Soil Survey (1973) reports: "The somewhat higher base status derived from ferro-magnesian minerals may have something to do with the prevalence of hardwood trees in the Cobequid Mountains and the rich undergrowth there, but this effect is difficult to separate from the adverse effect of exposure on the conifers."

Plants
Most of the Region falls within Loucks' Sugar Maple, Yellow Birch-Fir Zone and these are the predominant species. Parts of the Region south and east of the Bras d'Or Lake are in the Sugar Maple-Hemlock, Pine Zone. The major influences on the regional vegetation are the fertile soils, cold winters and cool summers, good drainage, and relative lack of disturbance. The high elevation and well-drained fertile sites favour hardwoods or mixed woods, with softwoods appearing on poorly drained sites and cool, moist ravine slopes and valley bottoms. Shallow soils on parts of the plateau surfaces support only Balsam Fir with lesser amounts of spruce.

Sugar Maple, American Beech, and Yellow Birch are the main species on the hills. White Spruce, Red Spruce (mainly in the Cobequid Hills), and Balsam Fir form mixed or softwood stands on valley slopes, while Black Spruce, White Spruce, scattered Eastern Hemlock, and White Pine predominate on the valley bottoms. A prominent feature in this Region is the vigorous shrub growth, particularly of Mountain Maple, Witch Hazel, and Hobblebush. This shrub community develops in cut-overs and insect-killed stands, with the prominent addition of Rubus spp. Following disturbance, shade-intolerant hardwoods are found throughout but are more prevalent on lower slopes, mixed with spruce and fir. There are few bogs in this Region, but seepage sites are common.

Plants of the Alleghanian floral element, whose main range is further south, are associated with intervale habitat in this Region.

Animals
This Region provides a range of forested habitats but does not have significant aquatic habitats. It includes large areas which are relatively undisturbed and inaccessible, and provide good habitat for ungulates, bears, and the larger carnivores.

Cultural Environment
Specific sites by the Bras d'Or Lake were Mi'kmaq burial grounds, and these spots continue to be important to the Mi'kmaq today. In general, highland areas such as the Avalon Uplands were settled by Scots in the first half of the nineteenth century, when fertile valley lands were no longer available. Farmlands were established as forests were cleared; however, most emigrants were squatters on the land. According to the 1851 census, many backland settlers had cleared 10-20 acres, enough to pasture cows, sheep, goats and horses and to grow essential crops. Soils were often only marginally productive. For the majority of these highland emigrants, seasonal employment was sought in the Sydney coal mines, the fishery (particularly with American vessels fishing in the Gulf), and selling timber stripped from unprotected Crown land. Poor livelihoods and meagre agricultural potential led backland settlers to abandon their farmlands; consequently, successional forest regeneration of the land took place. Today, a limited amount of farming is practised. A century ago, 100,000 sheep roamed the uplands and meadows of Cape Breton but, with the waning of rural life, by the 1970s only 2,700 animals remained. Upland areas are now used for commercial maple syrup production and mining ventures; however, forestry is the dominant economic land use. The impressive upland scenery of these environs has attracted recreation and tourism.

Associated Topics T2.1 Introduction to the Geological History of Nova Scotia T2.2 The Avalon and Meguma Zones T2.4 The Carboniferous Basin T3.1 Development of the Ancient Landscape T4.2 Post-glacial Colonization by Plants T9.1 Soil-forming Factors T10.6 Trees T12.2 Cultural Landscapes T5.2 Nova Scotia's Climate T10.4 Plant Communities in Nova Scotia T11.10 Ungulates T12.10 Plants and Resources

Associated Habitats H3.1 Freshwater Open-Water Lotic H3.3 Freshwater Bottom Lotic H6.1 Hardwood Forest (Sugar Maple, Yellow Birch, Beech Association) H6.2 Softwood Forest (Spruce, Fir, Pine Association; Spruce, Fir Association) H6.3 Mixedwood Forest (Spruce, Fir, Pine-Maple, Birch Association)