| Site Description |
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| Highlights: |
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| A westerly site with a full Holocene sequence, and intact surface. Tephra and pollen works are underway. Glenwest Bog is a valuable teaching site. |
| PAST AND CURRENT RESEARCH STATUS |
| The bog is situated in a bend of the Glen river 4 km east of Garrison in Glen West Townland. The importance of this site has been recognised during the mid-1990s as the authors include an investigation of the site in an undergraduate field teaching exercise. As yet no investigations of the site have been published. The importance of this, the most westerly site of those detailed in this review, when viewed in the light of the deteriorating condition of all of the more easterly sites, makes it the finest site for teaching present and past lowland bog land ecology in Northern Ireland. As well as having a well developed pool system in which Sphagnum cuspidtum and Menyanthes, the most aquatic of the flowering plants that grow on bogs, are seen to thrive, there are also large hummocks of the uncommon Sphagnum imbricatum. The fossil record shows that this moss, rare in most sites throughout the British Isles today, was the commonest species of Sphagnum on lowland raised bogs until mediaeval times. The Sphagnum hummocks are large, one measured was 40cm high and about 150cm in diameter. There were however quite a large number of dead hummocks. Both Drosera rotundifolia and D. intermedia were common. Pinguicula was seen near the road but not further into the bog. |
| The western and part of the northern sides of the bog have been burnt recently. Much of the flora is regenerating, but most of the large Sphagnum hummocks have been killed and the pools seem to have degenerated. There are several patches of orchids to the northeast-side of the dome not far from the road. |
| This is the best preserved complete Holocene sequence in the area with the exception of Meenadoan. The deposits may extend back to include a full Late Glacial sequence. Basin profile studies carried out by QUB undergraduates since 1994 under the supervision of the authors' show that the site has a complex origin. The modern extensive valley bog has a lagg, which blends with the surrounding blanket peat. The basin profile indicates that the bog developed from one or possibly two ancient river channels. Bogs of this configuration are not common. |
| The presence of undisturbed deposits right up to the present day has enabled the site to be used for studies of mediaeval to recent vegetational change. The potential value of the site now is for its long record of Sphagnum accumulation, which can be used as a record of past hydrology and climate. The site is also an important teaching resource as it provides a good view of a raised bog pool and hummock complex without the damage that would follow from taking students onto the much more fragile surface of Meenadoan. |
| Description: |
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| Conclusions: |
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| There has been spade cutting on all the margins of the bog with the most recent cutting near the road. Old cuttings on the west side seem to have been abandoned some time ago. There are two active drains, one running from the dome in a north-easterly direction and the other following the line of the road. Both appear to carry considerable water from the bog. There is a bank and ditch running east-west near the north end of the bog, possibly of considerable age, which appears to be a boundary rather than a drainage ditch. |
| The most immediate and serious threat to the bog is from machine cutting that is encroaching onto the dome at the southern end. Activity here has extended considerably since September 1996. All efforts should be made to stop machine cutting as quickly as possible. Beyond the area where cutting has occurred there is a considerable area of surface damage from machinery driving over the bog and turning at the ends of the patches. The area affected by the machinery is compacted, pools and hummocks are lost and the Sphagnum species are replaced by Eriophorum and Triquetrum. |
| To the east of the road the bog thins out and grades into blanket peat, which is also being machine cut. It would probably be reasonable to sacrifice to cutting this area in exchange for preservation of the main bog dome. |
| THE FUTURE OF THE SITE |
| The bog is now under threat from mechanised surface cutting. This threatens the whole bog from the southern end of the site as machine cutting has extended significantly over the last two years. To secure the wellbeing of the site it is vital that all mechanised cutting cease. |
| Notes: |
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| For general information and references on the Late Quaternary and Holocene of Northern Ireland see the following site: |
| Key Site 101 - Introduction to the Late Quaternary and Holocene of Northern Ireland |
| For site specific information on the Late Quaternary and Holocene of Northern Ireland see the following sites: |
| Key Site 102 - Sluggan Bog Key Site 103 - Garry Bog Key Site 104 - Fallahogy Bog Key Site 105 - Slieve Gallion Key Site 106 - Garvaghullion Bog Key Site 107 - Claraghmore Bog |