Orchids are unusual, indeed exotic plants. After they have produced their flowers and they have been pollinated, the flower wilts and the ovary begins to swell to form a seed pod.  The time it takes for a seedpod to mature varies from species to  species, it may take eighteen months for a type of slipper orchid [Paphiopedilum].  When the capsule is mature, it splits open and its numerous, minute seeds are dispersed by the wind.  A single seed pod may contain millions of the dust-like seeds; a single seed may compared to a ‘speck of dust’.   Unlike the seeds of ‘normal’ plants, the seeds have no food reserve within them and in order to grow, they have to establish a symbiotic relationship with a specific mycorrhizal fungus.  This symbiosis is essential for the seed to germinate and grow.  The fungus enters the seed and provides the necessary nutrients for its development into a seedling. Propagating orchids from seeds is a complex process. sometimes done under sterile laboratory conditions using special culture media. In the wild, although an orchid may produce millions of seeds, only a minute fraction will successfully establish a symbiotic relationship with the correct fungal partner to grow and survive. Recent research with the orchid Cremasta variabilis has revealed some interesting facts about the germination of the seeds.  The orchid is found on the Korean Peninsula and is an insect pollinated, terrestrial orchid.  As with other orchids, its seeds are minute and are known to depend on a certain fungus to grow and develop.  In the past, most studies have focused on the fungi present in mature orchids but the team from Kobe University studied very young seedlings.  They noted that seedlings were often to be found near decaying logs, and this led them to test whether deadwood fungi are involved in early orchid development.   They buried seeds of four species of orchid in various forest locations, but they only observed germination  and seedlings near to decaying logs.  The seedlings were found to be exclusively associated with wood decaying fungi.  It may be that the orchids use other fungi to maintain the symbiosis as the deadwood dries out or is exhausted of nutrients. Some species of orchids have abandoned photosynthesis completely, and feed via fungi through their lives - a phenomenon known as mycoheterotrophy.  As woody (and rotting) debris represents a major carbon source in forests, it is a resource waiting to be exploited.  

Scientists from the Meteorological Office use radar data to track approaching storms and changing weather patterns.   The radar works by sending out pulses of microwaves, these bounce off rain drops and other particles in the air.  The time that it takes for this signal to return, plus its intensity gives information about the approaching weather. Early radar [during the Second World War] also picked the movement of ‘angels’. These ‘angels’ were later recognised as the movement of birds, bats and insects.  Scientists then had to develop techniques to remove this ‘biological scatter / material’, so that they could accurately predict storms etc. By removing this ‘biological component’ of the signal, a lot of biological information about the movement of birds, bats and insects was being ‘discarded’.   Now, scientists from the University of Leeds have ‘repurposed’ the radar data (from many radar stations, which scan the skies many times each day & night) but this time they remove the data relating to the weather.  This leaves information about the insects moving at a height of some 500 / 700 metres above the ground.  The results showed that some 11.2 trillion insects are moving during the day, and that this reduces to some five trillion at night.   Some of these insects are actively flying, but some are being carried by the wind  / thermals.  Furthermore, there were more insects above areas such as woodlands, grasslands and even urban areas.  However, the numbers were lower over intensively farmed areas, where plant biodiversity was reduced as compared to woodland or natural grassland.  The numbers were also lower where artificial lighting was high.   Other work by the CEH, Newcastle University and Butterfly Conservation, has involved surveys of grassland and hedgerows in southern England (Thames Valley) some of which were lit by streetlamp, others were unlit. The areas that were exposed to night time lights had roughly half the number of caterpillars as compared to the unlit areas.   In another study, LED lighting was set up in fields, and caterpillars' numbers in these illuminated fields were reduced.  The lighting may :- [caption id="attachment_40185" align="alignleft" width="300"] Cinnabar moth caterpillar.[/caption]   Deter nocturnal moths from egg laying. Make the night flying moths ‘easier targets’ for predators (such as bats). Affect the feeding habits of moth caterpillars. Whilst it would seem that night time light affects insects and the feeding behaviour of caterpillars,  quite how and why is yet to be determined.

Honeybees, bumblebees and butterflies are always cited as being important for flower pollination. Indeed, without them many of our food crops would ‘fail’.  But what about moths?  Well, recent research has found that they too are efficient pollinators.  A recent study compared the role of nocturnal and day time pollinators.  Much scientific research has focused on daytime pollinators, like honey bees and bumblebees, but little is known about the night time pollinators.  So a study was devised, which focused on the day and night visitors to bramble flowers. Bramble may be a bit prickly to us but for bees and other insects it is important source of nectar and pollen, from early spring through to autumn.  The study was carried out out in the summer moths (when night is only one third of the daily cycle).  Trail cameras were used to record visitors to the bramble flowers over three days, also special bags were used to cover the flowers for different times in order to determine the effectiveness of the different pollinators on pollination and fruit formation.  One group of the bramble flowers was covered up for the three days.  A second group was bagged up for the day time.   The final set was covered only at night.  The number of pollinator visits was recorded as was the resulting pollination and fruit formation.   At night, moths were the only insect visitors of the pale pink / white flowers of the bramble, and they also proved to be very effective pollinators. It is not clear why moths were more effective, perhaps the time they spend visiting a flower is a critical factor.  They do spend more time rummaging in a flower than day time insects [hoverflies, butterflies, bees etc].     There are only some sixty species of butterfly in the UK but over two thousand species of moth.  But like butterflies, moths are vulnerable with many of our larger moths in decline.  The challenges that they face as the same as those that threaten many insects namely: Pesticides Habitat loss Climate change But moths face an additional challenge - artificial light at night. This interferes with the feeding behaviour of their larvae / caterpillars, it also affects the feeding and breeding of the adults.   Thus, moths are not only important pollinators but a vital component to the biodiversity of an ecosystem.  They also are a food source bats and birds. Moths can be helped by: By allowing a patch of brambles and / or wild flowers in your garden Persuading the council to allow wild flowers to grow and flourish on roadside verges, ‘spare’ plots of land etc. Asking the local council to reduce night time lighting where it safe to do so.   At home, limiting the use of outdoor lights at night, draw curtains and blinds to limit light spill to the exterior. As insects are in decline generally, (see the  woodlands.co.uk splatometer blog) it is important to help our pollinators - ensuring that they still ‘have a home’ at the end of the day.  

 The red squirrel is a native species, it has been present in the British Isles since the retreat of the glaciers of the last ice age -so around for some 10,000 years.  The grey squirrel on the other hand has only been here since the mid nineteenth century, when it was introduced from America.  Though relatively small numbers were introduced at stately homes, it did incredibly well and they spread out from their original sites, colonising woodlands and spreading across the country.  As the grey squirrel spread so the red squirrel retreated and its numbers declined. Recent population estimates suggest that the grey squirrel population may now be as high as three million, whereas the red squirrel numbers are probably less than 300,000. The grey squirrel is to be regarded as a pest.  Why ? (a).   They strip bark from trees.   This is the main type of damage type of damage. The squirrels remove  bark to access the sap tissues underneath. [caption id="attachment_42793" align="aligncenter" width="675"] Squirrel damage[/caption] (b).   They cause the death of trees.  The damage to the bark and the underlying tissue can affect the flow of water and nutrients from soil to leaves.  It can also allow for the entry of pathogens (parasitic bacteria and fungi). (c).   Their activities have an impact on the quality of timber that can be harvested. (d).   They are associated with biodiversity loss, not only do they complete with and displace the native red squirrel, their presence can affect other woodland species such as songbirds (eat their eggs) and dormice. (e).   Grey squirrels pass on the squirrel pox virus to red squirrels.  Once infected the red squirrels tend to die of dehydration and starvation. [(f).   The grey squirrels that visit my garden dig up bulbs, like crocus, tulips and hyacinths.  They also make raids on soft fruits.] [caption id="attachment_42794" align="aligncenter" width="675"] Older damage by squirrels[/caption] There are measures to stop or limit grey squirrels from breeding.   One ‘extreme’ measure is shooting or trapping followed by euthanasia.  Another measure is the introduction of Pine Martens, they seem to control the numbers of grey squirrels whereas red squirrels have co-existed with Pine Martens in areas like north Scotland for many years.   However, the Governments Animal and Plant agency is developing a contraceptive.  This is a vaccine based product which causes the squirrel’s immune system to render both males and females infertile.   The vaccine induces the formation of antibodies against the animals own reproductive hormones. The idea is to fed it to the grey squirrels through feeding hoppers that grey squirrels can access but not red squirrels or other animals. The bait will need to be palatable and attractive to the squirrels. Should this prove successful, it will be a non-lethal way of reducing the numbers of the grey squirrel without shooting or trapping.   For detailed information on the squirrel contraceptive project, visit https://aphascience.blog.gov.uk/2024/09/30/reducing-grey-squirrel-overpopulation/ Similarly, lots of information on squirrel damage here : https://www.observatree.org.uk/media/1425/identifying-squirrel-damage.pdf  

The Earth has experienced many glacial and interglacial periods over hundreds of thousands of years.  Since the last ice age, the Earth has warmed (the average global temperature has rising by some 4 to 5oC) but the temperature rise was about 0.1oC per century.  Today's warmer climate took 5,000–8,000 years to ‘evolve’, during which time the average global temperature rose at a rate of around 0.1oC every century.   This gradual change allowed trees to adapt to the changing climate.  In the last century, ‘we’ have driven a 1.3oC rise just in the last century - this is some ten times faster than the change post ice age.  [caption id="attachment_35526" align="alignleft" width="300"] drought[/caption] Not only has the climate warmed, it has become increasingly unpredictable with heat waves, drought and torrential rain.  These can have dramatic effects on our trees and heathlands.  For example, the heatwave in 2022 resulted in Kew Gardens losing some 460 of its trees.  This last summer saw 4 periods of heatwave conditions.   So, it is not surprising that some of our most familiar trees are struggling with these changed conditions.  They are stressed, and it would seem that the climate is not likely to moderate in the immediate future.  In recognition of the changing climate, Forestry England has produced a 'species for the future' list.  The trees in the list are those which might thrive in a warmer climate. Whilst it includes familiar species like oak, birch, and alder, other species such as the coast redwood and Corsican pine are included,  which hopefully will create more resilient woodlands.  The trees are listed below Aspen (Populus tremula) Beech (Fagus sylvatica) Coast redwood (Sequoia sempervirens) Common alder (Alnus glutinosa) Corsican pine (Pinus nigra subsp. laricio) Douglas fir (Pseudotsuga menziesii) Downy birch (Betula pubescens) European silver fir (Abies alba) Field maple (Acer campestre) Grand fir (Abies grandis) Grey alder (Alnus incana) Hornbeam (Carpinus betulus) Japanese red cedar (Cryptomeria japonica) Lodgepole pine (Pinus contorta var. latifolia) Macedonian pine (Pinus peuce) Maritime pine (Pinus pinaster) Norway spruce (Picea abies) Pedunculate oak (Quercus robur) Red oak (Quercus rubra) Rowan (Sorbus aucuparia) Scots pine (Pinus sylvestris) Sessile oak (Quercus petraea) Silver birch (Betula pendula) Sitka spruce (Picea sitchensis) Sweet chestnut (Castanea sativa) Sycamore (Acer pseudoplatanus) Western hemlock (Tsuga heterophylla) Western red cedar (Thuja plicata) Wild cherry (Prunus avium) Wild service tree (Sorbus torminalis) The list contains both native and non-native species, the aim is to create through planting stronger and more biodiverse woodlands that can tolerate our changing climate over the coming decades.  The rate of climate change is the main issue. Whilst some of the trees already grow here, others come come from warmer / drier areas, such as the Mediterranean or  North America.  There are already many redwoods in the UK.  They were introduced in victorian times, when they were planted on the estates of the wealthy and landed gentry. There are now probably more redwoods in the UK than in their native Pacific Coast range,  there intense heat and dry weather has exposed them to intense forest fires. Another possibility to promote resilience is to use seed produced by trees such as Oak that has been ‘produced’ by trees growing in warmer regions. The inclusion of trees that might be suited to our changing climate is often referred to as assisted migration.  However, the introduction of non-native species is not without its problems, for example the introduced species could become of invasive or add to the burden of pathogens that our trees are exposed too.

Woodlands provide us with number of benefits They supply softwoods and hardwoods, which have variety of uses. They provide a variety of habits for many species of wildlife, adding biodiversity to an area. They allow for a number of recreational pastimes. However, we and our woodlands need to prepare and adapt to a changing climate, one in which winters may be milder and summers hotter and drier.  Extreme weather events are also becoming more common.  So woodlands need to be resilient.  If they are resilient, then: They recover better from disturbances, like fire or disease Generally fare better when challenged by storms or floods. A number of government agencies have produced booklets / downloadable files (PDFs) on how to address the possible problems associated with the changing climate.  The advice seems to fall into three basic categories. Increase the range of trees in your woodland, promote diversity.  Look for trees that not only match your site (soil, aspect etc) but also might cope with future climate conditions.  If the climate is drier, then trees which have done well in the past might struggle in the new conditions.  For example, beech was noticeably affected by the drought in the summer of 1976.  Look for trees that can cope or unaffected by disease and insect pests and are from a reputable source and free of disease. Review the management of your woodland. For example, what and when to thin, create access and paths, openings or glades which can improve the diversity of the plants at ground level.  Paths and openings will also improve access within your woodland. [caption id="attachment_41085" align="aligncenter" width="674"] Woodland path covered with mast[/caption] When planting new trees, think about where the trees come from. What conditions do they are experience in their home environment, can they cope with drought. It may be that trees species that usually grow in more southerly areas of Europe will be better suited to the changing conditions. As mentioned above there are a number of publications / guides to help with increasing the resilience and diversity of your woodland.  Some of these are listed in the links below : The Climate Change Hub has a number of informative fact sheets and videos. Information about increasing species diversity from Natural Resources Wales. Improving structural diversity in woodlands from Natural resources Wales:  Forest Research has produced a detailed practice guide on woodland management and climate change. The Government website has numerous links and publications, eg. Advice of new trees and woodlands in light of climate change.

Autumn is here, whether you follow the definition of meteorological autumn, which starts on the first of September or the astronomical autumn which starts at the autumn equinox.  The equinox is when day and night length are equal, after that time the days get shorter. Or it might be that you are noting the signs of the seasons changing.  The BBC, the Woodland Trust and Nature’s Calendar chart the advance of autumn by recording events in the life of key species, for example blackberry, hawthorn, swifts, conkers, ivy and oak.  The information collected helps build a picture of how climate change is affecting the time of flowering, fruiting  etc. of many species. The blog has already commented on the early flowering of the blackberries but now woodlands are starting to transform into a mosaic of reds, yellows, and oranges as the leaves prepare to be shed and the woodland floor becomes a fungal jungle, (as Jasper has described). Hawthorn, Blackthorn and other bushes are laden with berries, conkers and acorns will be strewn across woodland floors. Squirrels eat hazelnuts (and hide some of them as a winter food store).  This banquet of fruits and seeds may be a response to the long, hot and very dry summer we have just experienced.  Trees and shrubs have been stressed by the heat and drought. Some have responded by mobilising their reserves / efforts into producing more fruits and seeds, to ensure that they pass on their genes to the next generation.   [caption id="attachment_24651" align="aligncenter" width="600"] Sloes on Blackthorn[/caption] If it seems like you have been noticing more acorns on the trees than normal that could be down to a "mast year”. Mast years occur roughly every five to ten years and refer to years when certain species of trees Like oak & beech) and shrubs produce a larger than normal crop of berries, nuts and fruit.  This boost in production means far more is produced than can be eaten  by the usual herbivores, squirrels, dormice etc, thus ensuring at least some of the mast goes on to grow new plants.  However, this ‘over-production’ can come at a cost to the tree, using vital resources so that growth in the subsequent year may be reduced.  Quite what causes trees and shrubs to ‘go mad’ and overproduce is not known but some theories are explored in a previous blog, though the weather in Spring is an important factor. [caption id="attachment_42689" align="aligncenter" width="675"] Collecting acorns.[/caption]

This year's Spring saw a number of fires damaging important UK wildlife habitats.  In Northern Ireland, wildfires have often spread through gorse, which is widespread, often dry and flammable.  One such fire occurred at Slieve Beagh.  The area is mainly blanket bog, with small lakes and streams.  The fire here raged for three days and has destroyed a large area of blanket bog.  It was described as a ‘hot burn’, in that it advanced slowly and burned deep into the blanket bog. Hotter and drier Springs have contributed to greater amounts of dry material,  The bog is the habitat of the hen harrier - an endangered species, as well as being important site for migrating and over-wintering birds. [caption id="attachment_42436" align="aligncenter" width="675"] Moorland[/caption] There will now been a concerted effort to restore the area, which was designated a RAMSAR (wetland) SITE in 1999 and is an area of special scientific interest.  Whilst the burnt area is now green again, the new vegetation lacks the variety of original plant species.  Much is grass, which could contribute to another fire; it will take many years for species like sphagnum moss, bog myrtle and bilberry to return. Sphagnum moss creates a habitat that helps in formation of. Peat.  Peat forms in wetland conditions, when water accumulates and oxygen is limited slowing the rate of decomposition.  If the bog flora can be re-established, then insects will return and, in turn, the birds.  An absence of predators, coupled with suitable weather would see successful broods of chicks raised, and a functional ecosystem restored. The RBCT (River Blackwater Catchment Trust) is working with various agencies to create a fire plan. Burns apart from destroying the habitat, release vast quantities of carbon dioxide from the stored carbon in the peat.   The plan is to include  the introduction of grazing, which should help control the amount of accumulation of flammable vegetation, and  make use of technology such as drones to find and fight fires.   Drones might also spot people, who are frequently responsible for such fires.