That smell we love so much, that has even been bottled into a scent is the distress call of your freshly cut lawn. It is the release of a chemical defense and self administered first aid from the hundreds of thousands of injuries you just inflicted with your precious lawnmower.
Plants release a whole number of volatile organic compounds called GLV’s (Green leaf volatiles) normally. Whenever a leafy plant is injured it starts to release them in high numbers with some of the compounds stimulating the grown of new cells which help the wounds heal quickly. Some compounds will help the plant by acting as an antibiotic or antifungal aid.
More interestingly it can be used as a distress signal by plants to warn other plants of incoming danger giving them time to put up a defense. An example of this is when giraffes eat acacia trees. Giraffes have developed the understanding that if they approach an acacia grove from down-wind then, as they eat the acacia, the distress signal sent will blow away rather than towards the other trees. This allows the giraffes to continue munching their way through the other trees. This distress signal allows the acacia tree to release a chemical into the leaves that make them taste foul to the giraffe.
Geocoris punctipes
Scientists found, in one study, that the saliva of certain caterpillars reacts with the compounds released by coyote tobacco plants to make them attractive to the Geocoris punctipes AKA “big-eyed bugs” that regularly eat the caterpillars.
There may be a high cost to that wonderful smell of freshly cut grass, though. The compounds released are precursors to ozone formation, according to researchers, and can contribute to the formation of photochemical smog in urban areas.
So, we are all stuck indoors and only allowed out for our one form of exercise a day.
Today, for my one form of exercise, I thought I would take you on a short 15 minute journey through a small wooded area that is local to me. Warren Farm, which although separate, is part of Nonsuch park in Cheam.
So this is for you, the person who can’t go out on their usual walk in the park or woods, or would like to know more about what our local parks have to offer.
It’s important that we observe the rules of lockdown so I have filmed this as one continuous shot only pausing to look at the plants and trees we come across during our journey.
Below is the information for the photos that I have added to the end of the video.
Peacock butterfly – I mention this when we look at nettles Click the link for a look at my video and post of a peacock butterfly.
Silver washed fritillary – Unusually for a butterfly, the female does not lay her eggs on the leaves or stem of the caterpillar’s food source (in this case violets), but instead one or two meters above the woodland floor in the crevices of tree bark close to clumps of violets. When the egg hatches in August, the caterpillar immediately goes into hibernation until spring. Upon awakening, it will drop to the ground, and feed on violets close to the base of the tree. The caterpillar usually feeds at night, and usually conceals itself during the day away from its food source, but during cool weather will bask in the sunny spots on the forest floor on dry, dead leaves.*
Orange tip butterfly – The first butterflies to be seen each year are ones that survive the winter by hibernating in adult form, such species as the brimstone and peacock can even be seen on mild winter days. Not many butterflies are born from pupae as early as April but the orange-tip usually manages this feat.*
Small blue butterfly – Britain’s smallest butterfly is easily overlooked. Its sole food source is the plant kidney vetch. Males perch on tall grass or scrub. From late afternoon onwards they can be found in communal roosts, facing head down in long grass. The butterflies live in small colonies which are declining in most areas. Found throughout Britain and Ireland but rare and localised.
Common blue butterfly – Measuring 35mm it is one of the most widespread butterflies in the UK. The common blue caterpillars like to feed on birds-foot trefoil.
Cinnabar moth – Day and night flying moth with a black body and red hindwings, it is commonly found on ragwort where it feeds and pupates.
Ferns and the Fibonacci sequence – Ferns are a good example of how the Fibonacci sequence is found within nature. Plant growth is governed by this sequence and is known as the ‘law of acclimation’ the sequence is created by adding the last two numbers in a sequence to find the subsequent number. 0-1-1-2-3-5-8-13-21-34-55-89… 89 would be added to 55 to get the next number = 144 and so on. This sequence describes how things grow, how trees branch out, how flowers form and how ferns, like bracken, unfurl.
Mossy rose gall – Diplolepis rosae is a gall wasp which causes a gall (that mossy growth) known as Robin’s pincushion, or moss gall. The gall develops as a chemically induced distortion of an unopened leaf or bud, mostly on field rose or dog rose. Up to 60 eggs are laid within each leaf bud. The grubs develop within the gall, and the wasps emerge in spring 99% of which are female.
Lichen – 1800 varieties in the uk and 17000 globally. Lichens cover approximately 6% of the earth’s surface. Lichens are a symbiotic relationship between and algae and a fungus. Simply these fantastic lichens can be split into three broad categories;
Crustose – firmly attached to surface and cannot be easily detached with a fingernail
Foliose – leafy lichens and can be easily lifted away with a fingernail. They may also appear to have fine roots.
Fruticose – Bushy lichens attached at one point and look more like plants.
Six spotted burnet moth – A daytime moth that has 6 distinctive red (occasionally yellow) spots set against a black body on each wing. Commonly found on grassland and meadows feeding on thistles, and scabious.
Speckled wood butterfly – Prefers the dappled light of woodland and likes to feed on honeydew which is produced by aphids when they feed on the sap.
Let us start with some background information about fungi and how they interact with the environment.
We all, generally, see something that has a stem and an umbrella type head and say ‘mushroom’ or ‘fungus’ however this is not really the complete fungus. What you are looking at is the fruiting body of some types of fungi (plural of fungus) which have emerged from the ground, plant, or tree.
The main part of the fungus that develops the fruiting body is known as ‘mycelium’ and lives within its hosts. Many fungi live independently in soil; others have a symbiotic or parasitic relationship with plants or animals.
Some trees use the mycelium network that runs throughout the soil to send messages to each other. When one tree is being attacked by a pest it sends an ‘i am being attacked’ signal down its trunk, along its roots and the fungi*, attached to the tree roots, picks up this signal and sends it along to the neighbouring trees in which the fungi is also attached. This allows the trees to send out hormones, pheromones or any other defence to protect itself.
Families of fungi
There are over 99,000 species of fungi currently known and these can fall into one of four main categories:
Basidiomycota (Club Fungi) – mushrooms puff-balls, smuts, rusts, and toadstools
Ascomycota – yeast, ruffles, cup fungi and mildews.
Zygomycota – found on decaying food like cheese and bread.
Deuteromycota (imperfect fungi) – So called because they lack sexual reproduction. They reproduce with spores known as conidia which are asexual. This type of fungi cause disease in humans like ringworm and athlete’s foot – both of which are fungi.
Along with bacteria, fungi help digest decaying and dead matter which digest the organic matter externally before absorbing it into their mycelia. They can be a great source of food, as long as you know what you are doing. One of the best uses is in medicine like penicillin. Which is derived from the fungi Penicillium.
Up to 60% of fungi have fruiting bodies and use these fruiting bodies to reproduce by means of spores. An average head can produce an impressive 16 billion spores that are then carried on the wind.
The largest living organism on earth is thought to be a specific honey fungus that measures 2.4 miles (3.8 km) across and is located in the Blue Mountains of Oregon.
Here is a selection of 12 rare, not so rare, edible and deadly fungi.
1. Common earth ball – is very numerous during the summer and autumn months, in and around damp woodland in rich peaty soil or moss.
2. Puffball – Come in many varieties and get their name from the cloud of spores that are released. Unlike some other fungi the puffball produces its spores internally and releases them in a ‘puff’ when impacted like raindrops or an animal brushing past. While it is edible it can be confused with the younger versions of the Death cap and the Destroying angel, not something you would want to do.
3. Death Cap – The most deadly fungus known and is common in England. It is responsible for most fatal mushroom poisonings worldwide. Ingestion of just half a cap can lead to death.
4. Destroying angel – A pure white, deadly poisonous mushroom. One piece of this fungus is enough to kill a group of people. A particularly nasty fungi as once poisoned you start to feel better and then you die.
BeefsteakFly agaricTurkey tailPuffball
5. Amethyst Deceiver – A beautiful coloured mushroom, the amethyst deceiver likes to grow beneath beech and oak trees, turning brown with age.
6. Fly agaric – Probably the most iconic mushroom there is, made famous in fairytales and paintings, often associated with Alice in Wonderland when Alice was given a piece of Fly agaric to eat. That said it causes psychoactive and hallucinogenic episodes and should not be eaten. It can often be found under birch or spruce trees. It’s said that shamans used to collect fly agaric and give it to the younger members of the tribe who would have the hallucinogenic properties of the fly agaric, but also with the sickness that comes with it. The shamans would then drink the urine of the younger tribesmen after it had been filtered through the kidneys and liver giving them the high without the sickness.
7. Shaggy ink cap – AKA ‘lawyer’s wig’ gets its name from the inky like secretions that are produced when it spores. It will dissolve itself once it has spored or has been picked, usually within hours. It is edible when young, but because it dissolves it does not remain edible for long. it is also similar to the Magpie inkcap.
Magpie inkcapShaggy inkcapLemon discoYellow brain
8. Lemon disco – This bright yellow fungus grows on dead hardwoods, that have lost their bark, including oak and appear ‘jelly like’. Usually seen in their hundreds, they grow in a small cup shape unlike its cousin the common jelly spot which is smaller and blob shaped.
9. Yellow brain – AKA ‘witches butter’ is so named for obvious reasons. An edible but flavourless fungi. It lives on dead wood and will shrivel and expand depending on how much rain there is.
10. Jelly ear – Fairly frequent in Britain and Ireland as well as in most countries of mainland Europe and parts of Asia and North America, the Jelly Ear fungus is seen mainly, but certainly not exclusively, on dead Elder wood in damp, shady locations.
11. Ox tongue – Also known as the ‘beefsteak’ mushroom due to its resemblance to raw meat. It likes living or dead oak and sweet chestnut and is fairly common. This mushroom is edible and the wood of infected trees develop brown rot which makes the wood richer, darker and of great interest to the furniture building trade.
12. Turkey tail – So called due to its resemblance to a turkey’s tail. Its latin name, Trametes versicolor, refers to it being many different colours. A good one to look out for on rotten tree stumps.
Death capEarthballJelly earAmethyst deceiver
I hope you get a chance to see some of these amazing organisms and now know not all is what it seems within the damp world of fungi.
Please note: You need to be an expert to pick edible fungi this information is for education not consumption. Some can cure you and others can kill you and most look alike, assume all are deadly.
*Symbiotic fungi, meaning fungi that exchange this service for sugars or moisture from the roots of the tree.
Many plants that we see and love in the U.K. are not native to us. They are either long established and have become part of our ecosystem with the damage done further back in history or they are non-invasive meaning they pose no current threat to the ecosystem. Many invasive plants were released in the 18th and 19th century when budding botanists collected plants from around the world, continuing to grow them here in the UK not knowing the damage some can do when released into the environment.
There are currently around 70 NNIS (non-native invasive species) of plants and wildlife that are causing damage around the U.K. The ones I mention here are some of the more common or dangerous ones found in our gardens and countryside, most are a criminal offence to plant or sell, if you discover any of these plants then please contact the relevant body for advice on removing. You can find this list of NNIS here.
Plants
Giant Hogweed – Originally from Russia,giant hogweed looks like our native hogweed except, as the name suggests, it’s giant. Regular hogweed grows up to around 2m and poses no threat to humans. Giant hogweed however, can grow up to 5m!Â
It’s sap, when skin is exposed to it, can cause blistering of the skin and permanent damage because it removes the skin’s ability to process UV light. Even tiny amounts of sap are dangerous with the effects lasting at least 20 years!
It also, like many invasive species, out competes other local flora and it’s roots damage the soil around riverbanks leading to unnecessary erosion and an increased flood risk. The flower heads (umbels) can produce 50,000 seeds each which makes control of giant hogweed difficult.
Himalayan Balsam – A stunning plant in its own right, Himalayan balsam comes from west and central Himalaya and can grow up to 2m tall. It loves river banks and damp woodland and establishes quickly in clumps. It’s seed pods explode and fire small seeds that are then carried by the wind. Because it spreads easily and grows along riverbanks it can slow the flow of surface water entering the river when it rains and as a result can cause localised flooding. There is a popular trend amongst some of the more ecologically minded to go ‘Balsam Bashing’ where teams of people attempt to control the spread. Conveniently It is easily removed, as it has a small root structure and can be pulled by hand from the soil.
Japanese Knotweed – This is a hugely successful plant at reproducing. It does this by using rhizomes. Rhizomes are underground plant stems that send out roots and shoots to produce more plants) or viable parts of it’s stem.
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Knotweed grows in clumps as it spreads using it rhizomes and its roots have the power to work its way into, split apart, and destroy concrete and asphalt. Therefore it is extremely difficult and costly to remove. Houses that have Japanese knotweed on its land are usually unmortgageable because of the structural damage this plant can cause. To remove every trace of knotweed the soil for 2m below and around the plant must be removed and disposed of correctly, usually by a specialist company, as any fragments of the plant are viable and could create new plants thus spreading the plant. After that strong chemicals are used to try and control the growth of any remaining fragments. This process of removal can take up to four years to complete.If you think you have knotweed please visit this government site for more information.
Rhododendron – Native to south west Europe and southwest Asia. This beautiful plant is loved for its large vivid purple flowers and is commonly found around the U.K. in woodland and ecologically sensitive areas. Rhododendron is something most people will have seen growing wild at some point. Being so pretty It can still be found in many people’s gardens all over the country. It spreads easily as its small seeds are carried on the wind.
If left alone It can grow to cover a large area reducing sunlight and as a result restricting the growth of other plants beneath it. This has a knock-on effect to insects and wildlife that rely on those plants for life. Although it’s not illegal to plant rhododendrons I would suggest not doing it and removing it if you already have it.Â
Trees
Non-native oak trees – Worldwide there are over 600 species of oak tree, all of which can be found in the northern hemisphere. Of the 600 oaks only two are native to Britain with a further three commonly found non-native oaks. Native oaks are the English oak and sessile oak. The three non-native oaks are holm oak, red oak and turkey oak. Holm oak is the only evergreen oak to be found in britain and is used for firewood and it’s acorns for pig feed. The red oak is native to America and gets its name from the colour of its leaves in autumn which turn a deep shade of red. The turkey oak is native to parts of Asia and southeast Europe. The main concern is that it is the host of a type of wasp called the knopper gall wasp, which in spring forms small galls (a reaction from a plant or tree to grow a home for insects, very clever) within the catkins of the Turkey Oak. The female wasps that develop from these galls on the turkey oak then lay eggs within the acorns of the English Oak causing galls to develop and therefore affecting the fertility of the English Oak and reducing the viability of the acorns.Â
Red Oak (Quercus rubra) autumn leaf. Jersey Farm Woodland Park, Sandridge, Hertfordshire, 11 November 2012. A very lovely sunny autumn day!Sessile OakTurkey Oak GallTurkey OakHolm OakEnglish Oak
False Acacia – there is a road near me called Acacia walk and it has about half a mile either side of the road planted with these stunning trees. That is half of the reason why they are so popular, they are stunning with big golden cascades of flowers. The acacia spreads by ‘suckering’ that is that it sends new shoots up from around its base and spreading that way, more so than by its seeds. This suckering effect can damage, pavements and homes as it sends up shoots. The false acacia also has a tendency to rot and then drop the rotten branches causing obvious problems. It also casts shade, as many non-native species do, over the native trees and plants of Britain reducing their ability to grow.
For factsheets on NNIS then please visit this sitewhere they are listed by common name.
