Scots pine (Pinus sylvestris) dynamics in the Welsh Marches during the mid to late-Holocene

Abstract

Around 4000 cal yr BP, Scots pine ( Pinus sylvestris) suffered a widespread demise across the British Isles. This paper presents new information about P. sylvestris populations found in the Welsh Marches (western central Britain), for which the long-term history and origins are poorly known. Two new pollen records were produced from the Lin Can Moss ombrotrophic bog (LM18) and the Breidden Hill pond (BH18). The LM18 peat core is supported by loss-on-ignition, humification analysis and radiocarbon dating. Lead concentrations were used to provide an estimated timeframe for the recent BH18 record. In contrast to many other Holocene pollen records from the British Isles, analysis of LM18 reveals that Scots pine grains were deposited continuously between c. 6900–300 cal yr BP, at frequencies of 0.3–5.4%. It is possible that individual Scots pine trees persisted through the wider demise on thin soils of steep drought-prone crags of hills or the fringes of lowland bogs in the Welsh Marches. At BH18, the record indicates a transition from broadleaved to mixed woodland, including conifer species introduced around AD 1850 including Picea and Pinus. The insights from BH18 suggest that the current populations may largely be the result of planting. Comparison of the LM18 findings with other regional pollen records highlights consistent patterns, including a Mid-Holocene maximum (ca. 7000 cal yr BP), long-term persistence at low pollen percentages and a Late-Holocene minimum (ca. 3000 cal yr BP). These distinctive trends encourage further studies on refugial areas for Scots pine in this region and elsewhere.

A multi-proxy Holocene palaeoenvironmental record of climate change and prehistoric human activity from Lough Cullin, southeast Ireland

“…The decline of Scot’s pine has been well documented across much of Ireland, northern Scotland and England (e.g. Bennett, 1984; Bridge et al, 1990; Gear and Huntley, 1991; Lageard et al, 1999; Mighall et al, 2004; Pilcher et al, 1995), although recent studies have suggested the persistence of the taxa in certain regions (McGeever and Mitchell, 2016; Sassoon et al, 2021). Numerous competing hypotheses have been proposed for the cause of this reduction, from climate (Bradshaw and Browne, 1987; Mighall et al, 2004) to anthropogenic activity (Tipping et al, 2008), however Lough Cullin provides no conclusive evidence for the cause of this at the site.…”

‘Pine Decline or pine declines?’ Analysis and Interpretation of Bog-Pines from Wem Moss, Shropshire, UK

“…BCE, Q-1233) [78], whilst at Fenemere (11.5 km SSE of Wem Moss-Figure 3b), a similar decline occurred at 1890 ± 50 BP (16-302 cal. CE, SRR-2920) [79]. It has been suggested that this represented a dating discrepancy, due to pine woodland persisting on more freely draining soils or 'erroneous [at Crose Mere] due to in-washed old carbon' [88] cited by [74] (p. 121).…”

Pine Decline or Pine Declines? Analysis and Interpretation Bog Pines from Wem Moss, Shropshire, UK

“…In the Meres and Mosses Region a recent study of a peat core from Lin Can Moss (Shropshire -17 km SW of Wem Moss) has revealed a continuous pine pollen curve, although with low abundance (0.3 -5.4 % TLP), between 6060+/-30 (5198 -4847 Cal BC) and 270 ± 30 BP (1510 -1798 Cal AD) [90]. Sassoon et al demonstrated the similarity of Lin Can Moss pine record to previous palynological investigations in the Welsh Marches (north-east Wales and western Shropshire), in contrast to the intermittent representation of pine pollen elsewhere in Wales.…”