Just as the woodland blog has described the maidenhair tree as a ‘living fossil’, so the same phrase can be applied to the Dawn Redwood (Metasequoia glyptostroboides).  All species belonging the genus Metasequoia were thought to have died out sometime during the Miocene Period. The Miocene began 23 million years ago and ended about five million years back.  The Miocene saw the evolution of the first dogs and bears, the uplifting of the Alps and significant climatic changes such as the MMCO - the mid miocene climate optimum.  During the MMCO, the temperatures were above today’s average global temperature, which lead to drier conditions across the world with a consequent decrease in woodlands and an increase in a more open landscape.  The Metasequoias were casualties of this changing environment; the Metasequoia forests, which extended as far as 80oN,  disappeared.  Indeed, all species were thought to have gone but then in 1941, a living member of the genus was found in China - the water fir (as it was known locally).   Read more...

Some 90% of the world's plants, including many food crops, rely on animals for pollination (as opposed to wind or even rarer water pollination). The contribution of honey bees and bumblebees to these pollination services is vital but they are at risk due to: the effects of disease,  climate change  effects of pesticides and  habitat loss / destruction. Whilst it is sometimes possible to help hives / colonies of the ‘domesticated’ honeybee suffering from parasites / disease, ‘helping’ wild populations is a much more difficult proposition. Read more...

The blog has reported on moorland fires and the importance of peat-based ecosystems on a number of occasions.  However, a new report has raised serious concerns about the state of peatlands, not just in the U.K but across Europe and Scandinavia.   Many ‘peatlands are in a dry and fragile state’, so that rather than acting as natural carbon sinks, they start to release carbon.   Peatlands actually store about five times more carbon than forests (across Europe). Read more...

The honey fungus (Armillaria mellea) is a plant pathogen, found across the world. It colonises and kills a variety of trees and woody plants, producing yellow-brown mushrooms that appear above ground.  These are the fruiting bodies of a much larger organism, that can spread over large distances underground.  The honey fungus can grow and spread by means of rhizomorphs.  These act as a system of underground structures that invade and decompose wood and roots.  They allow the fungus to infect, spread and survive for long periods of time.  Once the honey fungus is present in a garden, it can be managed but rarely eradicated. Read more...

Radiant energy from the sun falls on the Earth; some of this energy is absorbed by the planet and its atmosphere.  Some of the energy is radiated back into space.  The balance between the absorbed and radiated energy determines global temperature.  This balance is changed by a number of factors - the intensity of the solar energy, cloud reflectivity, the absorption of energy by various gases or surfaces. The reflectivity of the Earth’s surface  (the albedo) influences the amount of light energy that is reflected back into space. Snow has a high albedo, that is, it reflects much of the light back out into space.  Dark objects (like conifer plantations) reflect less light / radiation and absorb more thereby trapping heat that would otherwise be reflected back into space. The amount of energy that is ‘retained’ is also influenced by the presence of particular gases in the atmosphere - the so-called 'greenhouse gases', notably carbon dioxide and methane.  The amount of carbon dioxide in the atmosphere has increased dramatically from 280 ppm during the 10,000 years up to the mid-18th century to 415 ppm (as of 2019).  This increase has certainly contributed to the changes in climate that we have witnessed in recent years - extreme weather events such as heat waves and flooding.   Read more...

It should be pretty easy, one would think, to recognise the various species within the Russula genus, or brittlegills, the bright-coloured little mushrooms that have been popping up vigorously across the country over the past few months. Their vibrant cap colours render them immediately conspicuous among the Autumn leaf litter surrounding the bases of the trees with which they form mycorrhizal relationships. while their shared features make them relatively easy to situate within this wide grouping. All are particularly prone to crumbling and breaking under rough handling and all have white or slightly off-white stems, gills and flesh, often exposed beneath the holes left in their vivid cap cuticles by snacking woodland creatures. Read more...

Globalisation is the process by which economies and cultures are drawn together; they become more inter-connected through the flow of trade, capital, people and technology.  This has occurred in part due to the rapid growth of air travel, container shipping etc. so that there are now massive movements of people and goods (both raw and manufactured).   One positive aspect of globalisation is that we have access to foods and materials from all over the world.  A downside is that disease, parasites and pests can ‘hitch a ride’ with people or materials and goods as they move across the world.   Plants and animals can also change their geographical range / distribution as a result of climate change.  The woodlands blog has outlined some of the problems associated with various ‘alien or invasive’ species, for example, Asian hornets, Read more...

In winter, woods can seem a bit ‘naked’ and empty. Trees and shrubs have entered into a dormant state in order to survive the rigours of the winter months. Their buds await the signals that herald Spring. Many birds will have migrated to warmer climes, some animals will be hibernating. Many insects will be spending the winter as eggs or pupae, whilst herbaceous plants will over-winter as seeds, corms or bulbs.  But on the bark of many trees and on the surfaces of fences and walls, there will be lichens – they are there in summer, winter, spring and autumn.  Lichens are rather unusual in that they are an amalgam of two (or occasionally three) organisms : a fungus and algae. They are symbiotic systems, where two partners work together for mutual benefit (occasionally there are more than two partners). The fungus makes up the bulk of the lichen’s structure (known as the thallus), but the algae (green algae or cyanobacteria) are essential as they can photosynthesise and provide the organism with carbohydrates.  The nature of the biochemistry and physiology of the lichen symbiosis is largely due to the pioneering work of Dr David Smith at the University of Oxford in the 1960's and 70's. Read more...