Inland populations of Juncus balticus (Juncaceae) in Scotland
Typically considered a coastal species in Great Britain, Juncus balticus Willd. also occurs inland as a native plant beside the Rivers Avon, Dulnain and Findhorn in NE Scotland (and beside the R. Lossie in the 19th Century). Here it is found at median altitude 290 m AOD (inter-quartile range, 249 - 341 m). It also occurs as a native at one inland loch-side, and was found beside another loch in the 19th Century. In total, J. balticus has been recorded beside inland rivers from 14 10 km grid squares. In its inland riverside habitat, J. balticus is overwhelmingly found within communities dominated by native plant taxa, primarily associated with infertile, moist to damp, weakly to moderately acid soils, with high levels of illumination. Few observers are familiar with seeing J. balticus at its inland sites, therefore it is possible that this species has been overlooked along other rivers and burns in NE Scotland, and perhaps elsewhere. The first record of J. balticus beside a road was in 1907, long before roads were widely treated with salt in the winter, but it was not until 1979 that a second roadside population was discovered. Roadside and trackside populations have now been found in 19 10 km grid squares. At most of these sites it is likely to be an accidental introduction. It is now more widespread on roadsides than along inland riversides. The isolated nature of the roadside populations indicates that there have been multiple independent colonisations. It is highly likely that additional roadside populations await discovery, and that further colonisation events will occur.
Copyright (c) 2019 Andy Amphlett
This work is licensed under a Creative Commons Attribution 4.0 International License.
Copyright and licence: Authors (or their employers) retain their copyright in articles and images published in British & Irish Botany and are not required to assign this to the Botanical Society of Britain & Ireland (BSBI). All that BSBI requires from authors is a license to publish the article in British & Irish Botany and make it freely available to all in pdf format under the terms of Creative Commons Attribution 4.0 International Public License, which also enables BSBI to reproduce components of the article in other BSBI outputs (eg. BSBI News, the BSBI website and/or the BSBI News & Views blog) for publicity purposes. The licence code can be accessed here: