Biological Flora of the British Isles: Ulmus glabra

Abstract

This account presents information on all aspects of the biology of Ulmus glabraHudson (wych elm) that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard 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 characters, herbivores and disease, history and conservation.2. Ulmus glabra is a large forest tree, and often an important canopy tree in ancient and semi-natural woodlands. It is primarily native to the north and west of Britain and much of mainland Europe. It is the only elm native to Ireland. It is the most distinct of the British elms in that it rarely suckers and sets abundant viable seed.Although found on limestone screes and cliffs, and hedgerows, it is primarily a woodland tree, especially on moist, basic soils. In many secondary woodlands, it often co-occurs with Acer pseudoplatanus and has ecological needs that are similar to Fraxinus excelsior. 3.Ulmus glabra has clusters of c. 25 hermaphrodite flowers appearing before the leaves on previous year's growth. Seeds are wind-dispersed, falling in April to July, but remain viable for only a few days. Nevertheless, seedling establishment can be abundant. Hybridisation with other northern European elms is common but hybrids are notoriously difficult to identify and therefore probably under-recorded.4. The health and survival of wych elm in Europe has been seriously compromised since the 1970s due to Dutch elm disease caused by the fungus Ophiostoma novoulmi, transmitted by elm bark beetles (Scolytus spp.). To the south of its Scottish stronghold, many elms are reduced to small trees regrowing from basal sprouts or seeds. These trees tend to be reinfected once trunk diameter exceeds 10 cm.Fortunately for its long-term survival, seed production usually begins a number of years before they are reinfected.

Long-Term Responses of Mediterranean Mountain Forests to Climate Change, Fire and Human Activities in the Northern Apennines (Italy)

“…Further, the Lago Verdarolo record shows that these forests established and flourished under limited fire occurrence (Figure 2 ), probably resulting from a very moist climate (today’s mean annual precipitation is 2500 mm). Indeed, the results of RDA and GAM suggest the dominant tree species (for example, Abies alba , Ulmus , Fraxinus excelsior , Tilia , Acer ) to have been rather sensitive to fire (Figures 3 B, 4 , S4), in agreement with previous short-term post-fire monitoring (for example, Delarze and others 1992 ; Hofmann and others 1998 ; Thomas 2016 ; Thomas and others 2018 ) and long-term paleoecological studies (for example, Tinner and others 1999 , 2000 ; Rey and others 2019 ).…”

Assessment of the long‐term impact of deer on understory vegetation in mixed temperate forests

“…The response of minor tree species to the impact of red deer was similar to that of sycamore. Elm and rowan seedlings are shade‐tolerant (Raspé, Findlay, & Jacquemart, ; Thomas, Stone, & La Porta, ) but can grow quickly when gaps are formed and have the potential to escape browsing (Żywiec & Ledwoń, ). However, in our study both elm and rowan saplings were only present in the absence of deer, indicating that browsing pressure was too intensive to allow them to escape the browse layer.…”

The first record of Botryodiplodia canker in Poland

“…The two most devastating diseases affecting elms worldwide are elm yellows caused by elm phlöem necrosis mycoplasm and Dutch elm disease caused by Ophiostoma ulmi and O. novo‐ulmi (Boudon‐Padieu et al, ; Harwood, Tomlinson, Potter, & Knight, ; Thomas, Stone, & La Porta, ; Webber, ). Elms may suffer also from a number of cankers occurring on stems and/or on twigs.…”