B: Major Natural Disturbances

From Forest Walk Notes:

B: Major Natural Disturbances:
1.Wind – Gap Disturbance (frequent), & Stand-replacing Disturbance (Hurricanes, much less freq.)
2. Disease/Pests*
3. Fire
*Hemlock Wooly Adelgid (expected); Beech Bark Disease (beetle/canker fungi, Arrived Hfx late 1800s) Beech leaf-mining Weevil (Arr. Hfx ~ 2006); Emerald Ash Borer (Arr Bedford, 2018) – all associated with invasive spp.

More Info

It’s a fundamental tenet of ecology that “natural disturbances” such as wind, fire and pest/disease outbreaks play a major role in structuring plant communities and hence whole ecosystems.

A disturbance occurs, setting a plant community back to an early successional stage; it then goes though a sequence of stages until again disrupted.

In general, the species composition and relative abundance within plant communities  is determined in large part by the types of natural disturbance that are most prominent.  So for example forest stands that are subject to repeated fire as the major disturbance, e.g. as in the boreal forest, are likely to differ in species composition from forests that are subject to repeated wind as the major disturbance, as in NS.


Disturbance (Wikipedia)

Lit on Natural Disturbance Regimes of Eastern Canadian Forests

On major forest pests/diseases specific to our area

– On Eastern Hemlock: HWA (Hemlock Wooly Adelgid). Not yet observed in Sandy Lake Park, but it is nearby, and we need to keep a lookout for it.
View HWA in Nova Scotia

– For info on forest pests in NS more generally,   see NS Forest Notes/Forestry/Pests