Heritage is usually interpreted as something very solid: the wood, stone and concrete of our towns and cities, or the iron and steel of bridges and railway lines. I like to broaden that viewpoint to include our natural heritage, the plants and animals that compose our local environment. So in celebration of B.C. Heritage Week, I chose sphagnum moss, the fascinating plant that forms local bogs.
Sphagnum clearly qualifies as heritage under the “ancient” category: the moss found in Fraser delta bogs began accumulating over three thousand years ago and is now many metres deep. In the wet heart of Burns Bog, the largest and most well-known of our local bogs, layers of sphagnum, fed by rainwater, have grown into a dome five metres above the surrounding delta. The spongy moss draws up groundwater and increases the water’s acidity. Other plants and animals find it difficult to survive in this acidic, nutrient-poor environment, unless they are specifically adapted. Even the bacteria that cause decay cannot operate well here, so the sphagnum and anything within it are slow to decompose. The resulting ecosystem is totally distinct from the surrounding landscape and has species of plants and insects that normally inhabit more northern latitudes. As well as Burns Bog, there are bogs in Richmond and along the Fraser River. In Richmond Nature Park, you can walk on the quaking bog, where the ground wobbles and trembles due to the spongy sphagnum below.
Sphagnum has no root system but just keeps elongating its spindly, thin stems which clump and tangle into cushiony structures. It is composed of two cell types, the larger, empty ones being highly water absorbent, and the smaller ones providing the chlorophyll that colours the plant. Sphagnum is considered to have natural antiseptic properties. As a consequence, it was used historically for babies’ diapers, treating wounds, and other personal hygiene. Some First Nations’ women used the soft moss to carpet an expectant mother’s birthing room and line the baby’s cradle.
The lower, brown, slowly decaying layers of sphagnum become peat. Burns Bog peat was systematically excavated from trenches during the Second World War and used as packing material for armaments. After the war ended, the peat was dug and sold for horticultural use. Around the world, peat bogs began to disappear as they were dug out. Today, people are beginning to better appreciate the beauty and fragility of bogs, a vital part of our natural heritage.