This morning,  the Today programme (Radio 4) featured an interview with Kevin Martin ( Head of Tree Collections at Kew) and Chris Packham (environmental compaigner).  They were explaining the ongoing effects of this summer’s hot and dry weather.  Mr Martin said that the trees at Kew were “ tired, they have had a stressful summer”.  The result is that many trees are entering their dormant stage, moving materials from aerial regions to the roots - much earlier than usual.  The colour changes in leaves and leaf drop do not usually occur until well into October but this year such changes are already  proceeding apace.  Kew has been able to put some mitigations in place, for example, the watering of young trees which have yet to establish extensive roots systems. This is not true for trees across the UK, where young saplings in particular may have been affected by the dry weather and successive heat waves, [plus increased browsing by the extensive deer population]. Chris Packham spoke of “climate breakdown” and “environmental chaos”, noting that an oak tree near him was ‘festooned with acorns’, but they were only the size of peas.  Normally acorns would fall later in the year as food for wood pigeons,jays, squirrels and badgers.  Jays help ‘plant’ oak trees by distributing acorns.  He said that whilst local hawthorns were red with berries, which would normally be food for winter thrushes later in the year, the berries would now be dried up / shrivelled when the birds arrived to search for them.  Though lots of hedgerow fruit [e.g. sloes, rose hips, blackberries] is being produced, it is being produced at the wrong time.  He also commented on the scarcity of mole hills as moles are forced to burrow deeper in the soil in search of earthworms etc. As the seasons change, some plants and animals adapt. For example,  blackcaps from Northern Germany fly to the UK rather than Spain to overwinter.  During a relatively short period, their wing length has changed, actually shortened - a case of evolution in action.  However, many species are struggling.   The  wet summer of 2024 was particularly difficult for butterflies, as evidenced by the data collected by the Big Butterfly Count. Nature's timings are now ‘out of sync’, plants and animals are further impacted by extreme weather events, flooding, high winds and extreme temperatures. [caption id="attachment_24651" align="aligncenter" width="600"] Sloes on Blackthorn.[/caption] https://www.metoffice.gov.uk/about-us/news-and-media/media-centre/weather-and-climate-news/2025/double-record-breaker-spring-2025-is-warmest-and-sunniest-on-uk-record  

Back to one’s roots? Some of the effects of agriculture are very obvious, such as the vast areas of land now covered by monocultures of wheat or oil seed rape.  The expansion of mechanised agriculture has resulted in significant reductions in biodiversity, for example, through the loss of hedgerows and ponds (see the post on ghost ponds in Norfolk).  However, agriculture has others effects that are not quite so obvious.   Soils are ‘filled’ with roots, and roots help engineer landscapes.  They help: break up bedrock, improve permeability of the soil to water  stabilise the soil,  store carbon transport water and minerals to the plants.   They have been doing this for millions of years since the colonisation of land by plants. Now, research by scientists in the United States, has shown that the roots of agricultural crops are significantly less deep than those of  the  natural vegetation in an area.  Indeed, the root depth may be shallower by some 60 cm, compared to the natural root systems of an area.  If the soil is less root material then there is  decreased carbon storage,  reduced nutrient recycling and  possibly reduced soil stability.   Whilst there are some areas where “woody encroachment” is occurring (for example, shrubland taking over in some grasslands and forest advance into regions of tundra so root depth is increasing) -  the onward march of agriculture is dominant. Full details of this analysis / research : https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2022EF002897 Shrinking in winter Recent research has shown that some small mammals (like moles and shrews) shrink in size during periods of cold temperature.   This shrinking is thought to be a response to cold temperature rather than lack of resources.   This change in form has been known for some 70 years and is referred to as Dehnel’s phenomenon.  Professor Dehnel observed this change in form in shrews [in Poland in 1949].  However, shrews have a short lifespan so an extended studied of this phenomenon with these animals was not / is not possible.   Recent studies by German researchers have focused on moles, who can survive harsh winters by becoming  smaller.  It is thought that this reduction in size enables energy savings.  According to Dr Dina Dechmann this reduction in size comes at a cost, as the animals’ cognitive behaviour is affected. Further information here : https://royalsocietypublishing.org/doi/10.1098/rsos.220652 Farming and sustainability With the expansion of farming, less and less of the land is available for our native plants and animals,  Hedgerows and ponds have been lost / removed, natural habitats have been reduced. The government has produced new guidance on environmental land management schemes (ELMs).  That is subsidies that will be paid to farmers if they help promote and protect nature and improve the environment (e.g. using less insecticide and reducing pollution). There would be payment /subsidies for some 280 measures, for example : Creating fenland from lowland peat Maintaining sphagnum moss Creating land that could produce organic fruit Establishing a skylark plot Adding organic matter to the soil Creating green cover over winter (on 70% of the land) Welcome as these measures might be, there is criticism that they favour big arable farmers and do not really help those working on more marginal land (such as upland and moorland regions). Further information available here. Trees - From Root to Leaf For those who like their trees, here is a new book about them.  Written by Paul Smith -who was head of the Millennium Seed Bank of the Royal Botanic Garden, Kew.  Not read or seen a copy but the Sunday Times comment "'Stunningly illustrated and detailed ... a celebration of all things arboreal, from the seeds, leaves, flowers and fruit to the diversity of trees and how they have influenced art, culture and science' suggests that it might interest.  See "https://press.uchicago.edu/ucp/books/book/chicago/T/bo186012850.html"  

The People's Trust for Endangered Species (PTES). the British Hedgehog Preservation Society and Dr Paul Bright (Royal Holloway) have been studying the hedgehog population to see how it is coping with changes in farming practices, urban developments etc. The general conclusion is that the numbers of this mammal are declining – see the woodland blog. The mole, like the hedgehog, is insectivorous and there is concern about its numbers. It is thought to be one of the most common wildlife mammals in the UK, but we do not really know how many there are, nor where they are! Read more...