Biological Flora of the British Isles: Pulmonaria officinalis

Abstract

Summary1. This account presents information on all aspects of the biology of Pulmonaria officinalis L. (Common Lungwort) that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the framework of the Biological Flora of the British Isles: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characteristics, herbivores and disease, history and conservation. 2. Pulmonaria officinalis is a distylous, perennial rosette hemicryptophyte that is naturalized in Britain. It occurs predominantly in the understory of broadleaved, mixed, open woods rich in hornbeam, beech and oak, but is has also been recorded from hedges, banks alongside streams, (sunken) roadsides, built-up areas, gardens, rubbish tips, yew woodland and, less frequently, coniferous woodland. Its native range stretches from southern Sweden, in the north, to northern Italy, in the south, and from western Germany to Poland and Lithuania. It is most common in central Europe. 3. Pulmonaria officinalis reproduces both by sexual and vegetative means. The underground parts consist of a slowly creeping rhizome with adventitious roots. Despite the presence of an elaiosome that is attractive to ants that likely facilitates seed dispersal, populations often show a significant fine-scale spatial genetic structure and small neighbourhood sizes. 4. The leaves and flowering stalks are covered in hairs of varied length and stiffness, and stems and inflorescences are sparsely covered with glandular hairs. Flowers of P. officinalis are heterostylous, with distinct pin and thrum morphs. The corolla varies from purple, violet or blue to shades of pink and red, or sometimes white. The flowers are mainly pollinated by solitary bees and bumblebees. 5. Pulmonaria officinalis has significantly expanded its distribution in the British Isles since the 18th century, especially in southern England. P. officinalis is currently not regarded as threatened in Europe. Nonetheless, small, isolated populations of the species often show reduced reproductive success and lower genetic diversity, potentially affecting their long-term survival. Preservation of local habitat conditions by regular opening of the forest canopy and restoration of gene flow among populations are required to maintain viable populations of P. officinalis in the long term.

The functional role of temperate forest understorey vegetation in a changing world

“…The bulk of studies that we reviewed investigated how certain pathogens affected mortality or growth rates in specific understorey host species (Bayandala, Fakasawa, & Seiwa, 2016;Bayandala, Masaka, & Seiwa, 2017;Boyce, 2018), rather than investigating the role of the understorey for pathogen occurrence in general. Some of these speciesspecific studies focused on tree seedlings (Bayandala et al, 2016(Bayandala et al, , 2017Reinhart, Royo, Kageyama, & Clay, 2010), while others focused on herbaceous understorey species (Boyce, 2018;Elliott, Vose, & Rankin, 2014;Jefferson, 2008;Meeus, Brys, Honnay, & Jacquemyn, 2013;Warren & Mordecai, 2010). Several of these studies additionally address whether overstorey gaps influenced pathogen effects on understorey species (Bayandala et al, 2016(Bayandala et al, , 2017Boyce, 2018;O'Hanlon-Manners & Kotanen, 2004, 2006Reinhart et al, 2010).…”

Is sexual organ reciprocity related to legitimate pollen deposition in distylous Pulmonaria (Boraginaceae)?

“…In this study, we measured several floral traits and assessed for each population imprecision in floral sexual organs by calculating recently developed inaccuracy metrics (Armbruster et al 2017). Because in Pulmonaria (as in most other distylous species) pollen grains of L-morph plants are significantly smaller than those of S-morph individuals (Olesen 1979, Richards and Mitchell 1990, Champluvier and Jacquemart 1999, Brys et al 2008a, Meeus et al 2013, they can easily be discerned, making it straightforward to determine the contribution of legitimate pollen grains relative to the total amount of pollen deposited on a stigma. Therefore, patterns of natural pollen deposition were assessed on stigmas of the same flowers for which floral traits were measured to test the hypothesis that increasing deviation from perfect match between anthers and stigmas negatively affected the level of legitimate pollen deposition.…”

Climate change increases ecogeographical isolation between closely related plants

“…We predict that the ranges of Pulmonaria species will increase in their overlap under future climate scenarios compared with current conditions and therefore decrease the role of ecogeographical isolation as a barrier to hybridization in these species. However, because Pulmonaria species produce seeds that are adapted for ant‐dispersal (Meeus, Brys, Honnay, & Jacquemyn, ), it can be expected that this limits potential migration into new regions (Honnay et al., ) and climate change, therefore, has limited impact on ecogeographical isolation.…”