treeblog - Archive - February 2010

Hello friend! Welcome to the February 2010 edition of the Festival of the Trees, hosted with gracious humility by treeblog. It’s time to take another walk through Festival Forest, so please dress in suitable attire. Quickly pack yourself some refreshments too – tea and biscuits, beer and a Scotch egg, whatever – and then we can get off in time to see the forest sunrise. Maybe we’ll see the trees lit up like the little Appalachian glow that Carolyn of Roundtop Ruminations saw last week.

O-ho! What rustles? A friendly badger approaches! What’s it got for us? A piece of parchment? Ah, it’s a map of Festival Forest, annotated by one of the Forest Guardians, Jade Blackwater. These green ‘X’s must be things she wants us to take a look at. Yep, these’ll fit into our walk nicely. The first one isn’t too far in this direction, so we might as well make it our first port of call… Aye, there’s a note attached to this tree. It’s a letter – sorry – it’s a poem entitled, Tu B’Shvat, by Rebecca of Rebecca’s Raps.

All photos in this post are Creative Commons-licensed and were found on Flickr.

Now, see that tree over there? That’s a myrtle beech. Over at Tasmanian Plants, David takes a look at how this tree from that island’s cool temperate rainforest managed to survive the most recent glacial period. And that scrub oak next to it? Greg of Greg Laden’s Blog tells us how a scrub oak in southern California has survived for an estimated 13,000 years by cloning itself. At that age it would have been a seedling in the last ice age, back when the myrtle beech was still chilling in refugia!

That tree by the stream is a western redcedar. It isn’t a true cedar though – it actually belongs to the cypress family. Western redcedar is the subject of a comprehensive post for The Clade by Rachel Shaw.

I don’t know what those twisting, barkless trees over there are, but I know that A. Decker has some drawings of them at Resonant Enigma. When it comes to identifying trees, things just got a bit easier for visitors to Riverside Park – the trees have now got little tags with their common and taxonomic names on, as Melissa of Out walking the dog discovered recently.

This part of the Forest is a lot colder than the rest (I hope you brought a coat). That freezing creek could have been the inspiration for Angie’s haiga at woman, ask the question. And that hoar frost… the way it transforms the leaves and the bark and the grass and everything is just magical. It’s not just the Forest either – take a look at Silvia’s photos of her wintry back garden at Windywillow. Kitty has another couple of frost photos at Into My Own.

Hard frozen ground plus dormant trees plus a prolonged episode of rainfall can all add up to a flash flood, something that occurred in Dave Bonta’s neck of the woods recently at Via Negativa. To top it off, the temperature dropped and the floodwaters froze!

The frost here is pretty deep. Er, it’s snow. Pretty deep snow. Outside the Forest, Chestnut Coppice and Sweep Wood took a decent hit of snow – Mike’s got a hefty photo-record over at Peplers in Rye. Eped of fish without faces has arranged some very wintrous photos of the infamous Donner Pass, whose subjects include staghorn lichen and the incredible-impossible phenomenon of snow rollers!

Isn’t this Forest strange? We’re barely taken a hundred steps from the snow and already there’s a flowering tree that closely resembles the pink poui in Gillena Cox’s webshots album, Scenery & Nature: Trees Bloom.

Some trees hold secrets… swamp4me at SwampThings shares a live oak with a mysterious wound. Who or what inflicted it and why? Is everything what it seems? All we know is, the tree lives on... What if a tree grew up next to a barbed wire fence and grew around the barbed wire, but at some later date the fence was taken down to leave behind a secret section of barbed wire buried deep inside the heart of the tree? Vicky reveals the secret at TGAW.

Hey. You feeling the bad vibes in this area? Those stumps over there were once healthy trees. I hate it when trees in the Forest have to be cut down, but the powers that be can be ignorant or unfair. Luigi at the Agricultural Biodiversity Weblog laments that his mother-in-law was forced to cut down some of her eucalypt plantation in Kenya under a government initiative to combat drought. Sometimes a tree has to come down in the interests of public safety, even if it’s a grand old vet. Michelle of Rambling Woods tells the sad story of Herbie, a victim of Dutch elm disease and New England’s oldest elm tree.

Have you ever noticed that some trees resemble animals? Somewhere in this forest there’s a silver birch that looks like a reindeer, and Shashi has a lizardy reptile-tree at his anAestheticbard photoblog. Speaking of birch trees, Sheridan at Willow House Chronicles recounts a Native American legend that explains the branch scars on birches with the story of Winabojo, a spirit-boy.

Hold on a sec, there’s an arrow made of sticks on the ground here! That’ll have been left by Dave Bonta, one of the Forest Guardians. Where does it point? At that tree down there with its bole all swathed with strips of material? That reminds me of a line from Marly Youmans’ poem A Tree for Ezekiel at qarrtsiluni.

Let’s just rest for a minute by this maple. I want to show you its twigs. Do you see those little wrinkles? Well, Seabrooke at the Marvelous in nature explains how by finding those wrinkles you can not only determine the age of a twig or branch, but also how much the twig or branch has grown in each year.

There was once a road that ran through the Festival Forest, but that was a long time ago. Today you could walk right by without noticing that a road was ever there. Once it fell out of use, the forest just swallowed it up. Rudyard Kipling poetised a very similar story in The Way Through The Woods, a fine poem to which Jasmine of Natures Whispers has added some fitting imagery.

You know, I never cease to be amazed by the sheer diversity of the trees here in Festival Forest. Over there are oaks, but over there are palm trees! The dedicated iphoneographer Bruce Moore shares a moody photos of a palm over at brucecmoore iPhone photos. When you say ‘palm tree’, I think ‘coconut’. If it’s a red hot day in the Dominican Republic and you fancy a refreshing drink of coconut milk, someone might just climb up and fetch you one. Moe at Iowa Voice has the photos! Still, not everyone likes palm trees. If only the haters would read Jacqueline’s passionate defence of palm trees at SAVING OUR TREES. The Alexandra Palm in her back garden is way more than just a ‘telegraph pole’ – it’s a valuable food source for birds and a possum!

And still with the palms, when Billy Goodnick saw a fig intertwined with a palm tree he got a little hot under the collar in this article at Fine Gardening. Mr Goodnick also gets excited about the colours of the leaves in autumn at Santa Barbara Edhat. I was apparently misinformed when I was told that deciduous trees turn yellow and orange and red because forest dwellers paint the leaves by the light of a full moon.

Jade Blackwater of Arboreality spent several months of 2008 living in Santa Barbara. Living next to a warm, sandy beach is all well and good, but if you’re a forest-dweller it might take some getting used to.

Are you a bonsai person? Or have you tried to keep one in the past? John Conn (b0n2a1) curates a gallery of spectacular specimens on Flickr called Bonsai.

The bare trees in this part of the forest are great to photograph against a beautiful, clear, blue sky on a fresh winter’s day. I’m sure Susan of Garden Rant would agree. A moody sky can work as well, like in these photos at Wanderin’ Weeta, snapped by the eponymous wanderer herself. A different approach to these bare trees delivers results just as pleasing, as Karen at trees, if you please demonstrates: photographing the shadows that the naked trees cast along the floor.

I can’t tell what flavour these trees are without their leaves on, but I’m pretty sure that they aren’t baldcypresses. I should be able to identify those in winter now after reading Genevieve’s post at Tree Notes. Actually, tell a lie - I do know what this tree is. Do you see those spiky balls hanging there? They’re sweet gum seed balls. I learned about these recently from Katie at Green-Wood Cemetery Trees.

Let’s stop by this pine tree for a moment and take a close look at one of these pine cones. These little winged structures wedged into the cone hold the seeds – Roberta will tell you more at Growing With Science Blog.

Have you ever fallen in love with a tree? Heather Cameron of A day in the Country has. Actually, she fell in love with a forest. AnneTanne of AnneTannes Kruidenklets fell in love with the English oak growing in the cornfield that neighbours her house. When the field came up for sale, guess what happened? I’m sure you’d do the same to keep the tree that you love safe.

Woah! That giant growth on that tree there! That is one fine burr. Almost as big as the one JSK saw on her ‘campground – dam loop’ walk at Anybody Seen My Focus?

I’ve heard that there are many old marker stones lost in this forest. Caroline at Coastcard tells of the Rufus Stone in the New Forest. The original stone was erected in 1745 to mark the site of an ancient oak tree, itself the site of a much older event: the death of a king in August 1100.

Shhh!. Stand still a minute and look where I’m pointing. Up in that Scots pine. A red squirrel. Red squirrels are native to Scotland, but they are under threat from the introduced grey squirrel, as Kevin of Fraoch Woodland will tell you.

Can you smell that salty tang in the air? We’ve walked right through Festival Forest and we’re about to come out onto a beach. There’s a flotsam- and jetsam-decorated tree (deceased) standing in the ocean that Nina of Ornamental will show you. And there’s just one last surprise before we get there: dancing clouds.

Well, I hope you’ve enjoyed your journey today (or however long it took us – time in this forest passes strangely). I think the best way to bring it all to a close would be to solemnly quote these words of wisdom from Pablo of Roundrock Journal:

I just like the idea of knowing that the forest is a busy place even when we’re not around. And it reminds me that there is always something interesting to see in the forest if I just take the time to look for it.

Super. There are just two things left to say:
1. Thank-you to everyone who contributed to this edition of the Festival of the Trees, and thank-you again to Dave Bonta for forwarding on a lot of submissions, and Jade Blackwater for going the extra mile with her submissions. It’s been a pleasure.
2. Next month’s Festival of the Trees (#45) will be over at The Voltage Gate. Send in your submissions to thevoltagegate [at] gmail [dot] com. The deadline is the 26th of February.

Toodleoo-the-noo!

Five favourite photos from 2009

A few weeks ago I had a look back through the photos that have appeared on treeblog over the last year and picked out my favourites. Then I agonised over whittling them down to a final five – my five favourite treeblog photos from 2009.

22nd January 2009 The Lonely Oak on Whitwell Moor at sunset. The Lonely Oak, an English or pedunculate oak (Quercus robur), is very probably the tree that I have photographed the most and very probably the tree that has appeared most on treeblog (excluding those that I’ve planted myself). It stands within a half-hour walk of my house, on one of my favoured walking routes; it has tons of character; and it is highly photogenic: it’s the Lonely Oak. This photo originally appeared in the 32nd edition of the Festival of the Trees (February 2009).

2nd February 2009 We received a pretty heavy snowfall at the beginning of last February. This was the first decent amount of snow we’d had in ages so I went on a walk to make the most of it. Out in the fields, the snow was drifting behind the walls. Walking along a footpath hidden beneath this drift, I was ploughing through waist-high snow in places. It was either that or slide down a gorse-covered hill! The wind blowing through the gaps in the dry stone wall was sculpting fantastic shapes… Millstones Wood can be seen in the left half of the background.

21st March 2009 Larch flowers – probably European larch (Larix decidua). The one on the right is a female flower, known colloquially as larch roses – they take a year to ripen into seed-containing cones. (The flower on the left is too undeveloped for me to tell whether it’s a male or female.) I find it quite humbling to think that that last spring was the first time I ever came across these beautiful little flowers. How did I ever manage to miss them before? Spring 2009 was a fantastic spring - loads of surprisingly warm days with amazing clear blue skies. I was regularly out and about making personal discoveries in the shape of alder catkins, hazel, goat willow, and, of course, larch roses. Saturday the 21st of March was one of those glorious halcyon days.

24th May 2009 The 24th of May was a beautiful day in early summer and I went out for a ride on the pushbike. I was cycling down a firebreak in a conifer plantation next to Langsett Reservoir when I spotted this perfect dandelion (Taraxacum officinale) clock almost glowing in the late afternoon sunlight as it filtered weakly through the trees.

12th September 2009 This whopping great fungus was growing from the base of a Scots pine (Pinus sylvestris) in Millstones Wood. I didn’t know what species it was at the time, but I now think it’s chicken of the woods (Laetiporus sulphureus). [Update (July 2010): Wrong! It’s a dryer’s mazegill (Phaeolus schweinitzii).] I took this photograph on a walk with my dad one lovely day at the end of summer. My main aim for the walk was to collect rowan berries - which are scheduled to be planted as treeblog Set D(r) this March - but it also took in Pike Lowe, Ewden Force, and some incredible moorland along the way. Perfect.

Pests, diseases, disorders, competing growth and unfavourable conditions (a field trip): the pests and disorders

On Thursday the 21st of January my arboriculture class set out from college on a field trip to see a smörgåsbord of pests, diseases, disorders, competing growths and unfavourable conditions afflicting a variety of trees in the vicinity of York and Malton. Some of them were new to me, most I was already aware of, but it made for a very interesting way to spend a day and we got to see some cracking trees. Here’s a quick run-through of the pests and disorders that we saw:

PESTS
January isn’t a very good time to see pests in Britain. I think the scene is a lot more banging in the summer months.

European rabbit (Oryctolagus cuniculus) - The field trip took place in a particularly harsh winter and the poor old bunny rabbits had resorted to stripping bark from trees. The damaged trees we saw formed part of a rough hedge along a field and were growing right beside a few rabbit burrows. The photo shows damage to an ash but we also saw damage to a tiny hawthorn (Crataegus). Bark stripping weakens trees (when trees are ring-barked / girdled all material above that point dies) and opens them to infection. [Other animals such as hares, deer and squirrels will also strip bark.]

Humans (Homo sapiens) – The example we saw was disfiguration of the bark by people carving initials or symbols. Graffiti has a negative impact on the aesthetic appeal of the tree and can open it up to infection. [Other examples of direct human damage: vandalism (breaking off branches), vehicle damage (usually inflicted by tall vans and lorries), and butchery by D.I.Y. / cowboy tree surgeons.]

Witch’s broom (Taphrina betulina) – T. betulina is a fungus that causes dense balls of twigs (that look like birds nests from a distance in winter) – witch’s brooms - to form on the branches of silver and downy birches (Betula pendula and Betula pubescens respectively). As far as I was aware* the fungus doesn’t have any significant effect on the health of host tree, although as witch’s brooms grow larger every year, I assume that they eventually become so heavy that the supporting branch will break.

[ * I found this abstract to a scientific paper by Spanos & Woodward (1994) ¹ online: The impact of infection by Taphrina betulina on the growth of Betula pubescens was studied in naturally regenerated stands in the North East of Scotland. Infection by T. betulina was associated with a significant reduction in height growth and poorer developmental tendency, vigour, and stem quality of B. pubescens, whereas diameter at breast height was little affected. Tree height was reduced by an average of 25% over all diameter classes, with the greatest effect in smaller trees. For brooms of 100 mm diameter and over, numbers and sizes were strongly correlated with diameter at breast height and tree age. Reductions in height and vigour were not correlated with the number and size of brooms present, but were more pronounced in younger, smaller trees.]

Included bark (to the left of the red line) in the crotch where two main stems meet on a beech.

Included bark - “Included bark forms when the bark of the branch and trunk squeeze together” (Shigo, 1991) ². “In crotches that have very narrow angles of attachment the branch bark ridge [a ridge of bark in the crotch] sometimes fails to expand outward and is swallowed by the growth of the branch and trunk. Each year thereafter, more bark is enclosed within the crotch. This condition is referred to as included bark… Included bark has long been associated with weakness in tree crotches since it is frequently seen in failed tree forks. It is easy to assume that the included bark prevents the formation of connecting wood between two stems and therefore reduces crotch strength. …branch attachments with included bark are inherently weak and should be removed” (Farrell, undated) ³.

Sphaeroblasts - Disappointingly, I don’t have a photo of these intriguing fellas. You ever seen a Malteser- to fist-sized ball in the bark of a tree? Those are sphaeroblasts, described by Strouts & Winter (2000) ⁴ as “Bark-coloured spheroid lumps, small or large… woody, bark-covered structures, being an abnormal development of a bud which has produced annually a woody sheath without ever producing a shoot. Harmless.”

Burrs or burls - The burr we visited on our field trip – seen in the photo above – was a huge burr on a good-sized oak. It formed in a similar way to how sphaeroblasts form – the difference I think is that the buds in a burr are on the outside of the bark, not beneath it. The buds seem to multiply like crazy and sometimes produce tiny little shoots that never amount to anything. As far as I know, burrs are harmless to trees. They’re supposed to be highly valued by craftsmen because of the spectacular grain of the wood inside.

A pair of oak marble galls (one not fully developed) [photo taken 15 January 2009].

Galls - We saw a few old marble galls on the oak with the massive burr. I mentioned these in a post in January 2009: oak marble galls [are] caused by asexual Andricus kollari larvae. A. kollari is a member of the family Cynipidae, “whose members are of special interest because most of them induce gall formation on plants and many of them display a marked alteration between sexual and parthenogenetic generations. They are called gall wasps… Most of the European species occur on oaks, although some species attack roses and certain herbaceous plants. There are about 90 British species.” - from Chinery’s Insects of Britain & Northern Europe (Collins Field Guide, 1993). Again, as far as I’m aware, galls don’t significantly affect the health of a tree in normal conditions.

¹ Spanos, Y. A. & Woodward, S. (1994). The effects of Taphrina betulina infection on growth of Betula pubescens. European Journal of Forest Pathology, 24 (5), 277-286.
² Shigo, Alex L. (1991). Modern Arboriculture. Shigo and Trees, Associates.
³ Farrell, Robert, W. (undated) Structural Features Related to Tree Crotch Strength (Thesis submitted to the Faculty of Virginia Polytechnic Institute and State University for the degree of Master of Science in Forestry). Available in PDF format from: http://www.treeworld.info/manualuploads/crotchstrength.pdf [Accessed 11th February 2010].
⁴ Strouts, R. G. and Winter, T. G. (2000). Diagnosis of ill-health in trees. The Stationary Office.

First signs of spring: alder and hazel catkins. A brief update on the treeblog trees.

Winter’s grip on the countryside is finally loosening! The weather may still be nasty, but the days are getting longer and the local alders and hazels have been blasting out their male catkins. The hazels in particular look rather spiffing, their pale yellow lambs’ tails creating welcome splashes of colour in an otherwise bleak treescape.

More male hazel catkins, or lambs’ tails. These photos were taken beside Broomhead Reservoir on Tuesday.

This year’s developing male catkins (cigar-shaped) and last year’s woody female catkins (egg-shaped) on an overhead alder (Alnus glutinosa) branch.

And now for a brief update on the treeblog trees, neglected on this blog for far too long. Sad face.

The two Scots pines look fine. The four grey alders are covered in buds; the top of grey alder No. 4 is dead, as suspected in September. Most of the cider gums look alright, although a few of them have picked up a bit of a lean. Cider gums Nos. 1 and 15 look like they have suffered some serious frost damage. Will they survive? No. 15 took a lot of frost damage last year and survived… The post-Set A goat willow (the seedling formerly known as PSAUS) has some nice big buds.

Most of the downy birches have just started opening their tiny little buds. A few of them may have died, and some of them look to have had their roots exposed over the winter, so some replanting may be in order this weekend.

Set C’s downy birch No. 2 on Tuesday (16th February – 342 days after planting), standing a fine one-inch tall.

None of the sweet chestnuts or beechnuts, planted in the autumn, have sprouted yet. I’m aiming to plant my rowan seeds, the other component of Set D, in March. They are currently undergoing pretreatment.

Finding a way (20th February 2010)

Linear shadows cast by a cluster of stick-like junior rowans growing around the trunk of their parent.

A stunted larch (Larix, probably decidua) surrounded by rowan saplings. This part of the moor is fenced off, presumably to prevent sheep grazing and thus promote tree regeneration (although one sheep had somehow gotten into the enclosure). Aside from this larch, the trees were mostly young rowans (berries, dispersed by birds), with several birches (tiny seeds, wind-dispersed). I also saw a holly (berries, dispersed by birds) and an oak (acorns, ???!).

A wee lichen growing on a wee hawthorn. None of the buds on the trees I saw yesterday were showing signs of opening just yet. Give it a month…

Help! Are these oyster mushrooms (Pleurotus ostreatus)?

These mushrooms were growing from the trunk of a barely-alive lime (linden) tree (Tilia sp.) in a northern English city. I’m almost certain that they belong to the genus Pleurotus, but I am unsure of the species. I’m thinking Pleurotus ostreatus, the oyster mushroom, but I’m not confident. Does anybody out there recognise these? Please email me (the address is on the right) or leave a comment below!