Autumn

Many horse chestnut trees in Norfolk are suffering from an infestation of the horse chestnut leaf miner which causes patches on the leaves to go brown in July and early August. Bad infestations will cause the leaves to become dry, brittle and brown and eventually they will curl and drop off. This leaf miner which is part of the life cycle of the moth Cameraria ohridella was first recorded in the UK at Wimbledon, London in 2002 but has rapidly spread northwards reaching Norfolk in 2004 and becoming widespread in 2006 and 2007. The good news is that trees are not killed by this moth. Despite the browning of leaves and early leaf fall there is no evidence that damage by this caterpillar leads to a decline in tree health, die back of branches, or tree death. Affected trees will releaf and flower the following spring so please do not chop down affected trees.

There are some simple actions which may help reduce the infestation to a tree the following year. Sweep up fallen leaves and burn them. Alternatively composting the leaves and covering them with a 10cm layer of soil or a 15 – 30 cm layer of other plant material will kill the pupae as long as the compost heap is left until May the following year. Leaf removal works because it eliminates the first generation of moths next spring and though trees may become re-infested later by the adult moths it will reduce the amount of damage to the tree. Be alert to other diseases of horse chestnuts such as bleeding canker which causes weeping lesions on the bark of trunk or branches. This disease can kill horse chestnuts and if this is suspected advice should be sought from a tree surgeon or arboriculturalist.

Picture by Elizabeth Dack

You can’t without identifying the fungus and that is not always easy. Literally thousands of species of fungus occur in Britain; only a few are really good to eat and only a few are deadly poisonous.

The old wives’ tales that only edible fungi have a peelable ‘skin’, do not blacken a silver spoon (!) when cooking and smell like mushrooms, are all totally wrong!

Most fungus fatalities in Britain (about one each year) are caused by the death cap which has white gills, a ring (or ‘collar’) round the stem and, usually, a greenish cap.

Picture by Cheryl Dye

Fairy rings are caused by the outward growth through the soil of fungal mycelium from the point where it originated from a spore. A number of toadstool species cause rings of darker (and often longer) grass where the fungal activity has released nutrients which fertilise the grass. In late summer or autumn fungus fruiting bodies (toadstools) may emerge in this dark zone. Some other ring-forming species ‘fruit’ without affecting the growth of the grass.

A well-fed lawn is less likely to show fairy rings – but also less likely to provide a habitat for interesting plants and fungi. It is said that watering the lawn with a dilute solution of Epsom salts (magnesium sulphate) will eliminate fairy rings but the best answer is to enjoy them! If you have young children, make up stories about the rings; if you have scientific inclinations measure the growth rate of the ring – typically 10-20cm in diameter each year.

Picture by Cheryl Dye

Honey Fungus is the commonest of the toadstools which form large clusters at the base of trees and stumps. The caps are often honey-coloured, sometimes darker, usually with small scales. The gills are pale brownish and there is usually a ring (or ‘collar’) round the stem. Another clue is the presence of tough black threads (‘bootlaces’) under the bark of affected wood. In fact, this fungus is one of the most variable of our common fungi. The other common clustering fungus on stumps is Sulphur-tuft, smaller and yellower than Honey Fungus and it has dirty-greenish gills. It does not attack living trees.

Honey Fungus is a killer of trees (and some herbaceous plants) but it can take several years after the appearance of the toadstools before the tree dies. Removing them won’t help because it is the mycelium within the tree’s tissues which is causing the harm. Honey Fungus continues to consume the wood after the death of the tree.

Preventing the spread of the fungus is a major undertaking (involving digging, plastic barriers and a fungicide called Armillatox) but is rarely worth the effort. The good news is that it typically attacks the odd tree and rarely decimates a garden or wood.

Picture by Elizabeth Dack

The risk is small but not zero. Most lawn toadstools are harmless but some of the small brown ones can cause upsets and hallucinations. The only seriously poisonous toadstool which is common on lawns is the Ivory Funnel-cap (and its very similar relative). This has a creamy-white cap (sometimes with a hint of pink or grey) 2-4cm across and often slightly irregular (not really funnel-shaped despite the name). The gills are similarly coloured and quite crowded (closely spaced). It often occurs in loose clusters. Dogs have been known to die from its ingestion but human fatalities are rare and may never have occurred in this country.

Picture by Howard Stone

There are many garden flowers which provide nectar attractive to both butterflies and bees. If you want to attract butterflies try and ensure that you have some nectar producing plants in flower from late winter and early spring all the way through until late summer and autumn. There are a huge range of plants that butterflies will feed from but among the best are mint, catmint, marjoram, oregano, buddleia, iceplant, honesty, sweet rocket, lavender and wallflowers.

The nectar from ivy flowers in autumn is very attractive to red admiral butterflies. Remember too that fallen fruit in autumn will be fed upon by red admirals, commas and peacock butterflies.

Wildlife gardens should also include the food plants for butterfly caterpillars. A small patch of nettles in a sunny location may attract red admirals, commas, peacocks and small tortoiseshells to lay eggs. Holly blues lay their eggs on holly (first generation) and ivy (second generation), orange-tips on garlic mustard and painted ladies on thistles. So try and ensure both nectar for the adult butterflies and food plants for their caterpillars are available. For further information visit www.wildaboutgardens.org.uk
Picture by Jenny Johnson

You should clean your nest box out each year, you should wait until the autumn in case there are any second broods in the box. The Wildlife and Countryside Act 1981 only permits the cleaning out of nests between 1 August and 31 January, and states that any dead eggs must be destroyed. Make sure you wear gloves and wash your hands afterwards as nesting material can contain parasites and bacteria.

Picture by Elizabeth Dack

Solitary bees need pollen, nectar and mud. Ensure you have plants in flower from early spring to autumn and some bare areas of soil in your garden.
Picture by Elizabeth Dack

On warm sunny days you may observe the bees coming and going but when nests have been built you will see the ends of the bamboos sealed with mud (red mason bees) or small pieces of green leaves (leaf cutter bees).
Picture by Tony Brooks

This is actually quite a common occurrence, and is due to the tadpoles from the spring/summer missing the trigger for metamorphism. The reason for this could be due to the water temperature of the pond affecting the development rate, the lower the temperature the slower the development. A problem for many ponds is a lack of sunlight, this could be due to overhanging trees. Sometimes carefully pruning can let more sunlight into the pond and this will help the ponds flora and fauna life.

There is no need to worry about the tadpoles as they can actually over winter in the pond and once the temperatures increase the following year metamorphism will take place.

Picture by Hilary Tate.

The safest way to learn about fungi is to attend a fungi foray led by an expert. Autumn is a good time of year to see fungi, so look out for guided walks and events in your area during the autumn months. Organisations which host fungi forays include Norfolk Wildlife Trust, Sculthorpe Moore and Pensthorpe Nature Reserve and Gardens.

The East of England Tourist Board lists all wildlife events in East Anglia, so this is a good place to keep up to date with any fungi forays happening in your area. See www.visiteastofengland.com for more information.

Norfolk and Norwich Naturalists’ Society have a Norfolk Fungus Study Groups for further information visit http://norfolknaturalists.org.uk/wp/recording/specialist-groups/nfsg/

For lots more information about fungi, visit the British Mycological Society, at www.britmycolsoc.org.uk.

Picture by Jenny Johnson

It is impossible to be completely certain of how many species of fungi occur in a particular locality. Fungi are not a well-studied group, and are easy to miss, as the length of time between the emergence of a fruiting body and its decay can be very short. The British Mycological Society compiles a list of fungi species recorded throughout Britain, called the Fungal Records Database of Britain and Ireland. This database lists 2,289 species of fungi recorded in West Norfolk, and 3,262 species recorded in East Norfolk.

Picture by Ray Watson

Froglife run a “Toads in the Road” scheme. They will not be able to help in all cases but the guidelines for the scheme are on the website, click on this link (https://www.froglife.org/what-we-do/toads-on-roads/how-to-become-a-toad-patroller/), as well as all the information needed to apply for the toad crossing to be included in the scheme.

Picture by Annabelle Tipper