Woodland Watch Week 22 – 14/08/2013

This week, we’re focusing on just one of the creatures that have made the woodland their home not just here in the Woodland Watch wood but all over the UK. I have seen many of these little mammals racing about in the coppice canopy and even more evidence of them all around the wood through the last few months. Have you worked out what we’re talking about yet?…Yep, you got it…The grey squirrel!

The Grey Squirrel

The Grey Squirrel

The grey squirrel (Sciurus vulgaris) is a familiar sight all over Britain, despite being a non-native, and most would argue, an invasive species. Grey squirrels were introduced from North America in 1876 by the Victorians who considered them an exotic species. Since then they have spread throughout most of the UK, almost completely displacing the native red squirrel .

Grey squirrels are not fussy eaters, which to a certain extent explains their displacement of their red counterparts. They are mainly herbivorous, eating predominantly acorns, hazelnuts, berries, fungi, bark, buds and shoots. However, on rare occasions when food is scarce they will also eat insects, smaller rodents, bird eggs and nestlings. Red squirrels have a similar diet, but they are unable to digest seeds with high tannin content, such as acorns, which limits the food sources. They are also able to make much better use of unripe acorns and hazelnuts and this is clearly visible in the woodland.

Unripe hazelnuts broken open by squirrels for food

Unripe hazelnuts broken open by squirrels for food

Although my iPhone camera has let me down again here, you can get the idea! The woodland floor is littered with unripe hazelnut shells which have been split open by squirrels enabling them to get to the nuts for food before other species are able to consume this resource.

The introduced grey squirrel has been so successful in displacing its native cousin partly because it is bigger and stronger, able to find more food and store more fat in its body for winter. This allows it to out-compete the red squirrel, which has lower survival and breeding rates. A second reason is the Parapoxvirus, which causes a fatal infection in red squirrels. Grey squirrels are not affected, but act as carriers, spreading the virus to red squirrels in the vicinity.

As well as the feeding signs around the woodland, there are also a lot of signs of squirrel damage to the trees. Grey squirrels strip bark around stems and branches of trees. Bark stripping damage usually starts at the end of April and continues until the end of July (early September in high-risk years). Grey squirrels do not strip bark at any other time of year. Trees may be stripped anywhere on the main stem and branches, with vigorously growing and dominant trees generally being most affected.

An example of squirrel damage in the wood

An example of squirrel damage in the wood

The Forestry Commission have produced a great publication all about grey squirrel damage in woodlands which can be viewed at:

http://www.forestry.gov.uk/pdf/fcpn004.pdf/$file/fcpn004.pdf

Now, it wouldn’t be one of my blogs if there wasn’t some mention of eating something, so if you’re a vegetarian, you might want to stop reading at this point! Squirrel arguably provides one of the most ethical meats you can eat in the UK. Completely free range, low in fat and as the countryside is overrun with squirrels and population control is often deemed necessary, why not eat them?

There’s a great recipe here for spanish braised squirrel:

http://www.wildmeat.co.uk/orderform.htm?ac=EZKF4-6

Spanish Braised Squirrel

Spanish Braised Squirrel

While the woods have a lot of signs of squirrels, they’re not causing any huge problems here and are likely to be left alone at least for the near future. However, across the wider countryside, there are many areas where squirrels are causing major problems to woodlands and population control is an ongoing options.

As an arboricultural company we see many examples of squirrel damaged trees and I can certainly appreciate the need for population control. However I also hate to see any creature being wasted, so if we’re going to control squirrel populations, why not eat them?

That’s it for this week. Join us next week for another walk in the woods as we’re heading closer and closer to autumn.

Until then, enjoy your own walks in the woods!

Treecreeper Arborists – http://www.tree-creeper.com

Woodland Watch – Week 20 – 31/07/2013

Well, another week, another walk in the woods and I can’t believe that we’re seeing signs of autumn emerging already. It seems like only yesterday I was walking through the woods with thick frost underfoot and no signs of growth, then we came through the spring and everything slowly started to emerge and grow, heading into a massive growth spurt in late spring and early summer. Where does the time go?!

So, the first sign of autumn approaching emerged before I even entered the woodland. On my way to the wood I passed a young horse chestnut tree (Aesculus hippocastanum). The horse chestnut is a broadleaf, deciduous tree, commonly found in the British landscape but actually non-native to the British Isles. The familiar Aesculus hippocastanum is a native of the Balkans, and believed to have been introduced to Britain in the 1500s.

The species doesn’t make up a significant component of British woodlands except in a select few cases in Britain. Mainly found along strees and in parks and gardens, there are horse chestnuts to be found dotted as individual trees, either planted or self seeded, in many woodland areas. In this wood, there are several large, mature horse chestnut trees growing towards the south of the site.

Undoubtedly the most exciting thing about the horse chestnut, especially for children is its seed, known more commonly as conkers and you can start to see the developing conkers inside their green spiny shells on the trees right now.

Developing conkers

Developing conkers

The horse chestnut has become naturalised in the UK and many people would think of it as a native British tree. The wood tends to be rather weak, so has never been widely used for timber or wood products, although its absorbent properties do make it ideal for fruit racks and storage trays as it keeps the fruit dry, preventing rotting. Extracts from the leaves including aescin or aesculin are marketed as herbal remedies because of their anti-inflammatory properties and the trees also have wildlife value with the nuts providing food for deer and other mammals and the flowers providing pollen for insects.

From personal experience I can also recommend using the leaves if you’re caught camping or wild cooking without washing up facilities. The leaves provide a useful lather for scrubbing dirty plates which has helped me on many occasions after a wild cooked meal!

Unfortunately, more recently, horse chestnuts have been a cause for concern as people have watched the leaves turn brown long before autumn. As tree surgeons we have lost count of the number of conversations we have had with people asking what they can do about their “declining” horse chestnut trees.

Rather than re-inventing the wheel here, i’ll point you to a very good Forest Research article about the leaf miner which is affecting horse chestnut trees:

http://www.forestry.gov.uk/fr/infd-68jjrc

The trees in the woodland have not escaped this pest and are showing clear signs of infestation with the leaves starting to turn brown. Larvae of C. ohridella mine within the leaves of horse chestnut, and the damage caused by large numbers of larvae can be striking. Up to 700 leaf mines have been recorded on a single leaf under favourable conditions. Severely damaged leaves shrivel and turn brown by late summer and fall early, well before normal leaf fall in the autumn.

Signs of leaf miner infestation on horse chestnut leaves

Signs of leaf miner infestation on horse chestnut leaves

Now, on to a happier note and from childhood games we move on to hedgerow fruits! Autumn is a wonderful time of year for foraging in the woodlands and I can remember many happy childhood days collecting blackberries and sloes with my family and friends. Although we’re not into autumn yet and I certainly wouldn’t want to wish the remaining summer days away, the hedgerows are starting to burst with early signs of food production.

A common hedgerow tree which we have looked at earlier in the season is the elder. The flowers have now gone and turned to young berries, clearly visible in the hedgerows, still green and yet to ripen but promising a good crop in the autumn.

Elderberries starting to develop ready for autumn

Elderberries starting to develop ready for autumn

From elderberry liqueur to elderberry jelly, there are a great variety of things to do with this wonderful fruit. Mixing it with sweeter fruits like blackberries and making into autumn pies and crumbles brings back wonderful childhood memories! I’ll keep you posted on recipes over the autumn!

Now then, on to something a bit more scientific…Although there’s a lot of science in making elderberry liqueur! Last week we looked at the spores developing on the ferns around the woodland and I said I would look into sporogenesis! My understanding is still pretty limited, but we’ll take a brief look!

Sporogenesis is basically a long word which means “the production of spores”, although the terms is also used to refer to the process of reproduction via spores. Reproductive spores are formed in many eukaryotic organisms such as plants, algae and fungi. If you’ve ever brought home a piece of King Alfred’s Cake fungus and left it on top of the stereo (as I once did) you’ll know the mess the spores make as they spread all over the surface!

Fern spores

Fern spores

Spores are distributed in many ways including by wind and by water. Organisms such as the puffball fungi dramatically expel their spores into the surrounding environment in order to reproduce. In ferns, the spores are expelled at a microscopic level and can be viewed in this video:

http://www.youtube.com/watch?v=-xF83pHEx6Q

For those of you interested in some more of the science behind sporogenesis I came across this video which explained it to me! Although not exactly a cinematic masterpiece, it will give you the basics!

http://www.youtube.com/watch?v=c6JNu0Vra-4

Lastly for this week, I wanted to look at a tree which has captured my attention many times walking through the woods. Take a look at this mature oak:

Oak tree with burrs up the main stem

Oak tree with burrs up the main stem

Burrs are commonly found on trees as a rounded outgrowth on a trunk or branch that has filled with small knots from dormant buds. These growths result from the tree undergoing some form of stress, which could be an injury, virus or fungus, among other causes.

The largest burrs have been recorded at 26 feet, occurring in coast redwoods in the US and can encircle the whole trunk where moisture is present.

They yield a very peculiar and highly sought after wood used by furniture makers, artists and sculptors. Every time I walk past this tree I would love to know what is going on under the bark and imagine the beautiful things you could make with the wood.

Well, that’s it for this week’s walk in the woods. I’m sorry it has taken a while to get to you, but the Treecreeper team have been so busy this summer! Join us soon for another walk in the woods!

Until then, enjoy your own walks and let us know how you’re getting on!

The Treecreeper Arborists Guide to Looking After Your New Tree

Thank you for coming to talk to us at North Nibley Music Festival and here’s your guide to planting your new tree!

Following the expert advice you have been given in selecting your sapling, you should have a suitable species for your chosen site. Remember, trees are like children – you have to nurture them to help them grow up big and healthy.

Ok, you have your little sapling clutched firmly, and you want it to become a successful tree, so after all the work you will put into it over the next few years it will result in a nice patch of shade to relax in.

Relaxing under a tree

Relaxing under a tree

Firstly, make sure that the roots don’t dry out. We have gone to great lengths to ensure there is minimal disruption to the root system, but there is inevitably some damage to the very fine roots which do all the hard work like taking in water and dissolved nutrients in the soil. These are really important, and each time the tree is moved, more damage occurs to these roots.

At this time of year, the trees are using a fair amount of water, with moisture evaporating from the stomatal pores in the leaves which pull water up from the roots via capillary action. This means the water demand is really important. Ideally, trees should be moved over the winter, when the water demand is much lower, and the tree can cope with the shock more easily.

So in order to ensure the roots have their best chance of survival (and therefore the tree), we must give it the optimal growing conditions. This means digging a hole. It doesn’t have to be too big, as a rule of thumb you can work on around about four times the size of the root ball. You won’t have to dig deep either, as burying the roots too deep will kill or severely weaken the tree. Make sure when you settle the tree in the hole that the point where the roots start to spread out from the stem is at ground level.  Your hole should have gently sloping sides, which if your soil is clay based may become glazed by the back of the spade.This creates a barrier to the roots spreading out, so just loosen the soil all around the edge of the planting pit a little with the edge of the spade.

Digging the hole for your tree

Digging the hole for your tree

Put a bit of nice soft soil or compost in the bottom of the hole, enough to raise the tree to the correct height. While you can still see the roots, and want to use a stake (or a cane) now is the time. Push it down, making sure the roots are missed.  Now fill the rest of the hole with your nice soft soil, and give your tree a bit of a jiggle up and down, which will make sure all the little nooks and crannies are filled with soil. Firm the soil lightly as you go, until you reach the correct height. Stand up, admire your work.

Now, you can give your tree in its new home a good watering, until there is a bit of standing water on the surface of the soil. Depending on whether or not you feel like it, put a bit of mulch around the base. This both keeps the weeds down around the tree so it has less competition for nutrients, and also helps to retain moisture in the soil, so when we have our next hosepipe ban (you know, just before the flooding starts) there is a bit less watering to do. For mulch, just about anything will do. A bit of woodchip, grass cuttings, straw, bits of cardboard or even offcuts of carpet.

DSC00575_000

Now you have successfully planted your tree we hope it gives you many years of pleasure.  Remember, the best time to plant a tree is twenty years ago. The second best time is now . . .

For more information on looking after your trees at any stage of life, or if you get stuck planting your new tree, contact the Treecreeper team on 01453 844038 or email us at office@tree-creeper.com.

For more information about Treecreeper Arborists Ltd, head to our website at

http://www.tree-creeper.com

Woodland Watch – Week 15 – 26/06/2013

Summer seems to finally be here and although it is neither as warm or as predictable as we would like, at least it is not as cold as it has been! This week my walk in the woods was overcast, but warm and I hope you will join me to have a look at what is going on this week.

The grass in the meadow approaching the wood is getting taller and taller but closer to ground level you can see lots of little purple clover flowers.

Clover growing in the hay meadow

Clover growing in the hay meadow

This red clover (Trifolium pratense) is a native, herbaceous perennial plant which can grow 20-80cm tall. The genus is so named because of the leaf structure consisting of three leaflets, known as trifoliate leaves. Clover is an interesting plant, widely grown as a fodder crop and highly valued for its nitrogen fixing capabilities which increase soil fertility.

Nitrogen fixation is the process by which nitrogen in the atmosphere is converted into ammonia. In the atmosphere nitrogen exists as a diatomic molecule (the atoms go around in pairs, like oxygen). In this inert state it does not easily react with other chemicals to form new compounds. Nitrogen fixing nodules in the clover plant frees up the nitrogen atoms from their chemical diatomic form (N2) to be used in other ways.

Before the establishment of science, when peopled looked to religion and magic for medicinal cures, red clover was already playing a part in people’s lives. To early Christians, it was a sign of the Trinity while during the Middle Ages, it was regarded as a charm against evil. A mutation resulting in the well-known four-leaf clover is considered good luck when found, even to this day.

Heading into the woodland, the first difference that was immediately apparent was how dark the wood was compared to previous weeks. The canopy has now almost completely closed over with a hazel lower canopy and an upper canopy made up of a range of other broad leaf trees including oak and horse chestnut.

The woodland was noticeably darker now the canopy has closed over

The woodland was noticeably darker now the canopy has closed over

One of the lower level tree species that we haven’t yet touched on but which I have noticed on my walks is the holly (Ilex aquifolium). An evergreen shrub which most people can easily recognise it can grow 10-25m tall with sharp spiney leaves which last around 5 years. What many people don’t realise, and to the relief of tree surgeons such as ourselves, is that leaves on the upper branches of mature trees do not have spines as they are well out of the reach of grazing animals and do not require this particular defense mechanism. 

Lower leaves of a mature holly tree

Lower leaves of a mature holly tree

Holly is dioescious which means there are male and female plants, unlike the hazel which we saw developing the male catkins and female flowers on the same trees. The sex of the plants cannot be determined until they begin flowering, usually between 4 and 12 years of age. Between October and November, the flowers on the female plants will grow into red fruit which is eaten by birds and rodents.

Interestingly in the Irish/Gaelic ogham alphabet holly is called Tinne, a word believed to have originally meant ‘fire’. From this was derived the word ‘tinder’, referring to dry, inflammable matter used for kindling fire from a spark. This association between holly and fire has been known since ancient times when charcoal made from holly wood was used by armourers to forge swords and axe heads.

The holly will remain fairly constant through the changing of the seasons, but it is a highly valuable woodland species.

Sticking with the theme of trees, another species to note is the English elm. Once a classic English tree like the English Oak, the elm all but disappeared from our countryside after Dutch Elm Disease reached Britain in 1927.

Now, these small elm saplings around the edge of the wood, although relatively common at this stage of their lives, are unlikely to reach maturity.

English Elm saplings

English Elm saplings

The current DED epidemic is caused by the fungus Ophiostoma novo-ulmi which is dispersed by various elm bark beetles within the Scolytus genus. The fungus blocks water conduction, resulting in wilting and eventual death of the foliage.

The first signs of the disease are often yellowing/browning of foliage tips as the affected branches are gradually starved of water.  When the leaves fall, the remaining twigs often turn down to form ‘shepherds crooks’ which can be valuable for disease detection in winter.

The diagram below shows how the disease progresses.

Dutch Elm Disease

Dutch Elm Disease

Although the English landscape has certainly lost the majority of its mature English elms, the Ulmus procera species has not disappeared completely from the landscape. This is because the elm bark beetles require bark to be of a certain thickness for breeding to be successful.

When an English Elm is killed by the disease, some roots remain alive and new elms regenerate from these. This means that for every mature elm killed by DED, many more are able to replace it. We may not have many large elms, but there are millions of young elms growing all over the English countryside, such as these young saplings in our wood.

That’s it for this week. Join us again next week for another walk in the woods.

http://www.tree-creeper.com

Woodland Watch – Week 14 – 19/06/2013

It seems as fast as I get used to warm spring/summer weather everything turns around and its back to miserable grey again! This week wasn’t great weather for a walk in the woods, but me and the dog made it out anyway and here’s what we saw this week!

Despite the dreary looking sky and cold, blustery wind that felt more like early spring than early summer, the meadow approaching the woodland was still beautiful, covered in buttercups and a wide range of flora.

Stormier skies than in previous weeks as we approached the woodland

Stormier skies than in previous weeks as we approached the woodland

The buttercup family is comprised of about 2,252 species, including wildflowers and ornamentals, such as larkspur, marsh marigold and clematis. It used to be thought that the rich yellow of the buttercup made better butter from cows feeding in buttercup-rich meadows. This is a myth however, as we now know that the stem and leaf are actually toxic, especially to cattle, and the animals avoid eating it.

The meadow is full of a wide variety of flowers, herbs, grasses etc and I am the first to admit that my meadow species identification needs a lot of work, so please feel free to correct any mistakes!!! Species such as the common plantain and clover are widespread among the buttercups.

Ground level vegetation in the meadow approaching the woodland

Ground level vegetation in the meadow approaching the woodland

Inside the wood, the woodland floor has changed again. The green bluebell leaves from previous weeks have turned yellow and collapsed as they come to the end of their life for this year. The stems and seed pods are still upright, bare looking without their foliage.

Bluebell stems left after the leaves have wilted

Bluebell stems left after the leaves have wilted

While these areas of the woodland look bare now that the bluebells have died back, other areas are overrun with weeds. On entering the woodland area there are large patches of young brambles which will continue to dominate the vegetation where they can through the summer months.

Young brambles taking over the area close to the entrance to the woods

Young brambles taking over the area close to the entrance to the woods

Although generally considered a woody week and certainly difficult to eradicate once they become established, brambles are a very useful plant to a wide range of wildlife. Hundreds of creatures use brambles at different times of the year: Insects visit the flowers for pollen and nectar, including bumblebees, honey bees, hoverflies, wasps, butterflies, moths, flies and lacewings.Spiders spin webs to catch the bounty of visiting insects. Moths such as buff arches, peach blossom and fox moths lay their eggs on bramble as it is their larval foodplant. Blackbirds, thrushes, chaffinches, starlings, robins, pheasants, foxes, mice and other small mammals eat the fruits. Robins, wrens, thrushes, blackbirds, warblers and finches will nest in bramble and small mammals use it for protection from predators.

A weed the bramble may be, but it is certainly a very valuable woodland plant as long as it is not allowed to out compete other valuable vegetation. The key to any habitat is variety.

That’s it for this week. Join us again next week for another walk in the woods.

http://www.tree-creeper.com

Woodland Watch – Week 4 – 10/04/2013

Another week, another walk in the woods and thankfully there’s no denying that spring is finally here! The weather is warmer, the buds are starting to burst, the spring flowers are starting to agree that it is time to come out. After a long, cold and particularly dreary winter, it is wonderful to watch the woodland coming alive again with the signs of spring.

This week, I spent a lot of time looking at the many pieces of deadwood scattered around the woodland. All too often, woodlands and gardens are ‘tidied up’. Deadwood is looked upon as something to be removed. In some cases, removal is necessary to ensure safety however, when it is safe to do so, deadwood should be maintained as vital habitat.

photo (11)

Deadwood such as this cracked stem provides valuable woodland habitat

Removing or burning rotting timber can destroy valuable invertebrate habitat. Wherever possible, fallen, rotting wood should be left undisturbed where it falls. Fallen branches and other lying deadwood should be maintained in situ unless they pose a danger to the public. 

This woodland is full of both lying and standing deadwood and while it may look untidy, it is important to remember that nature is rarely “tidy”. Often the best habitats are found in areas that humans, with our inclination to impose order on our environment, leave unmanaged.

Standing deadwood, left in situ, providing a wealth of invertebrate habitat

Standing deadwood, left in situ, providing a wealth of invertebrate habitat

For more information on deadwood habitat, take a look at this publication from the Forestry Commission:

http://www.forestry.gov.uk/pdf/lifeinthedeadwood.pdf/$file/lifeinthedeadwood.pdf

The same flowers could be seen dotted around the woodland floor as in previous weeks, however there were noticeably more of them this week. Primroses and wood anemones blanket patches of the woodland floor and the brilliant green of the bluebell leaves shone in the bright sunlight.

Primroses are springing up all over the woodland floor

Primroses are springing up all over the woodland floor

For this walk, I decided to take the left hand circular path to make a change from the other routes I have taken and came across these rabbit holes. Out of interest, I loosely crossed some sticks over the entrance to the holes to find out whether they were in use.

Loosely crossed sticks over a rabbit hole to test whether it was in use

Loosely crossed sticks over a rabbit hole to test whether it was in use

Sure enough, the following day when i went back to check, the sticks had been pushed aside and fresh rabbit droppings were observed around the area.

Yesterday's sticks pushed aside by rabbit activity in/out of this hole

Yesterday’s sticks pushed aside by rabbit activity in/out of this hole

Joining the splashes of spring colour on the woodland floor are the lesser celandines  (Ranunculus ficaria) which have now started to make an appearance. A perennial member of the buttercup family, these native British flowers are widespread in woods, hedgerows and on the banks of streams.

Lesser celandines adding to the spring colour on the woodland floor

Lesser celandines adding to the spring colour on the woodland floor

Join us next week for another walk in the woods. Until then, send us your pictures of your spring walks in the woods to office@tree-creeper.com or post them on our facebook page.