Bogland

Frog among the bog mosses

An adult frog among the bog mosses in Liffey Head bog. The tadpoles live in the bog pools where they feed on tiny aquatic insects. The presence of multicoloured Sphagnum moss is a sign of an actively growing blanket bog. ( Richard Nairn)

copyright R. Nairn

Frog among the bog mosses
copyright R. Nairn

Frog among the bog mosses

An adult frog among the bog mosses in Liffey Head bog. The tadpoles live in the bog pools where they feed on tiny aquatic insects. The presence of multicoloured Sphagnum moss is a sign of an actively growing blanket bog. ( Richard Nairn)

copyright R. Nairn

Enlarge image

A dozen or more species of sphagnum may be woven together on the surface of a raised bog, each species a different, often vivid, colour and adapted to a particular niche in the mosaic of hummocks, hollows and pools. Their feathery tendrils draw rainwater, with its supply of mineral nutrients, into tubular cells in the leaves. These allow sphagnum to hold water that is twenty times the plant's dry weight (in World War 1, almost a million tons of sphagnum were collected across Ireland for use in absorbent wound dressings).

Bog Deal

In the foreground of the picture is bog deal. These are the stumps of pine trees found deep within peat and would once have lived on the bog when its surface was drier, forming a forest of Scots Pine. In the background of the picture is a cut over bog, with a pool and shrubby vegetation. Bogs are very important habitats, and very few intact bogs now remain in Ireland. Bogs can provide us with a glimpse into the vegetation and climate of the past. However, once the climate began to get wetter, pine seeds could not germinate on the wetter bog and the roots of existing trees drowned as the bog began to grow again. These trees stumps still exist in the bog because the low oxygen conditions in peat prevent decay.

Michael Viney

Bog Deal
Michael Viney

Bog Deal

In the foreground of the picture is bog deal. These are the stumps of pine trees found deep within peat and would once have lived on the bog when its surface was drier, forming a forest of Scots Pine. In the background of the picture is a cut over bog, with a pool and shrubby vegetation. Bogs are very important habitats, and very few intact bogs now remain in Ireland. Bogs can provide us with a glimpse into the vegetation and climate of the past. However, once the climate began to get wetter, pine seeds could not germinate on the wetter bog and the roots of existing trees drowned as the bog began to grow again. These trees stumps still exist in the bog because the low oxygen conditions in peat prevent decay.

Michael Viney

Enlarge image

The mosses' rapid, rain-holding growth and accumulation of dead tissue lifted the whole ecosystem up from soggy platforms of sedge-peat into domes of raised bog often many metres deep and hundreds of metres across. In the process, the surface vegetation lost its connection with nutrients from the soil and came to depend, instead, on minerals dissolved in rain. The rising peat held a huge amount of water - as much as 90 % of its volume, some of it in spring-fed pools, or in 'lenses' of water between layers of peat. The trees on the bogs died off and as the domes spread out and joined up they invaded and engulfed wide areas of low-lying forest and wetland scrub. Human movement became difficult in many parts of the midlands and the early farmers laid down tracks of brushwood between their 'islands' of drier mineral soil.