A bog walk uncovers plants with amazing adaptive powers

School is out for some of us, or nearly so for others, and black flies are on the wane. It’s time to take the children on a bog walk in search of plants that eat bugs.

Let’s begin with the basics: A bog is a standing body of water fed only by rain. The lack of circulation of fresh water through the bog results in poor oxygen levels, high acidity and slow release of nutrients through decomposition. Plants and animals that live in bogs must adapt to these harsh conditions.

A spongy layer of living sphagnum moss covers the surface of the bog, a patchwork carpet of green and red punctuated by small trees, shrubs and flowering plants. Adapted to life in a watery world, sphagnum moss has no roots, absorbing water from its environment through tiny leaves that are only one cell thick. It does the job well – each plant capable of holding up to 20 times its dry weight in water – because the photosynthetic cells in the leaf are surrounded by numerous storage cells that fill up with water during the spring. This stored water comes in handy during the dry summer.

Beneath the living moss carpet is a deep deposit of peat formed from slowly decomposing sphagnum and other bog vegetation. This peat provides the structural support for trees, shrubs and flowering plants such as the baked-apple berry, a member of the raspberry family that dots the bog with white flowers in late May and tasty berries in summer.

Decomposition of the bog peat is slowed by the high acidity and poor oxygen levels; thus nutrients are released slowly. The sphagnum moss absorbs most of the available nutrients, leaving little for other plants. Bog spruce trees with trunk diameters of only 3 inches may be 80 years old. Tamarack, the tall, pyramidal deciduous conifer of Maine forests, takes on the growth habit of a shrub in the bog.

Some bog plants, such as the pitcher plant, supplement the meager bog diet in a most unique way – they eat insects. A folded leaf emerging from the carpet of sphagnum serves as the “pitcher,” its interior filled with water and digestive juices. Attracted by the bright color of the leaf, the insect crawls onto the extended lip of the leaf and begins its journey into the depths. Downward-pointed hairs lining the inner surface of the leaf prevent the insect from climbing back up – it is trapped! – and eventually it falls into the soup.

The extra nitrogen provided by the digested insects allows the pitcher plant to thrive in a harsh environment and reproduce. In June, the bog landscape is dotted with the pitcher plant’s dark red flowers emerging on leafless stems from the carpet of moss.

In the Bangor area, you can find pitcher plants in Orono Bog, 600-plus acres of peatland located within the Bangor City Forest. If you find yourself in Down East Maine, journey to West Quoddy Head Bog at Quoddy Head State Park. Both of these areas have boardwalks that wind through the bog, allowing visitors to study the unique plants and animals that live there without disturbing habitat or getting wet feet.