treeblog - Archive - November 2008

Is that not proper mental? The Brown Bronto is manufactured by John C. Brown & Sons in the USA. According to the website,

The Brown Brontosaurus Brush Mower is a complete brush control system that performs year round clearing, even in the most difficult terrain. Running with as little as 18 GPM auxiliary hydraulics allows our mower attachments to be placed on just about any excavator, gradall, feller buncher, high-flow skid steer or custom machine.
...
Because of our unique design, with the appropriate hydraulics up to 15” material can be mulched and cleared while retaining the ability to still clear the small low-lying brush.

And if the monster in the YouTube video wasn’t enough, take a look at the Brown Bronto photo gallery. A wee Bronto ‘dozer and a double-Bronto train!

treeblog update (Set A, Day 590): grey alders & Scots pines

treeblog update time for Set A’s four grey alders and two Scots pines! Photography from this afternoon, 590 days after the seeds of Set A were sown.

(From left to right) I present to thee grey alders One, Two and Three. Still bravely holding onto their caterpillar-savaged leaves despite the ravages of autumn.

Scots pines Gamma (left) and Alpha (right). All of the juvenile needles on both SPs have now turned yellow, although it is tricky to see in this little photo (click the picture to see a larger version on Flickr). The adult needles, which are always arranged in pairs on Scots pines, stay green as these guys aren’t deciduous. Check out SP Alpha’s two little chimney sweep brush-esque branches. I predict great things from those next year.

Bonus “treeblog’s good for insects” photos

I found this excellent caterpillar right at the top of grey alder No. 1. Isn’t its head an incredible imitation of a bud! This was the only one I could see on the alders today – no sign of the other caterpillars.

Take a closer look at that awesome bud-head. My sister reckons it looks like a meerkat looking backwards over its shoulder!

A lovely leafhopper on grey alder No. 4. I saw a few more of these guys chilling around.

The next post should be the cider gums' turn for an update, weather permitting. ‘Til then, sayonara!

In the news: a massive conker collection & help squirrel-proofing your bird feed

There’s some weird news about these days. First, there’s the two brothers who’ve amassed a collection of 7,500 conkers. According to their father,

We heard there was supposed to be a conker shortage this year. But I reckon that's because we had them all.

Jolly good. That’ll teach them grey squirrels. Although now I suppose they’ll just be more likely to steal those nuts you’ve left hanging in the garden to see the birds through the winter. But don’t fret! The RSPB have been dispensing invaluable advice for keeping your nuts squirrel-proof. The trick is to dust them with chilli powder. Birds can’t tell the difference, but squirrels are yellow bellies when it comes to the hot stuff.

treeblog update (Set A, Day 597): cider gums

Welcome to a new-look treeblog! I think it looks pretty nifty, and I hope you’ll agree. But who has time to worry about aesthetics when there’s a brand new cider gum update in town? I was out in the chilly November air yestreen snapping photos of Set A’s most numerous species like some dendrological paparazzo, a whole 597 days since I planted those self-same eucalypts as tiny seeds. Oh! how they have grown!

Cider gums Nos. 1, 2 and 4. All in fine fettle, although No. 4 lets the side down a little bit with an unfortunate bend in the stem.

Cider gums Nos. 9, 10 and 11. Poor old No. 11 is not looking too healthy at the tip of the leading stem - a caterpillar has been at work here. I expect this tip will die off soon and we’ll be looking at a forker.

Cider gums Nos. 3, 6, 15: the weans. No. 6 looks to be making a concerted effort to leave behind its days as a runt, now looking as smart and healthy as any of the big uns did this time last year. On the other hand, No. 15 seems to be keeping a very small and compact form. Perhaps it’s practicing to become a bonsai.

There ends this latest update. You can now leave comments on the posts published here at treeblog - just click the link below. I always love a bit feedback.

treeblog's cleft-headed looper (Biston betularia) - larva of the peppered moth

A couple of posts back, in the most recent grey alders and Scots pines update, I published a couple of photos of a rather spiffing caterpillar pretending to be a twig on treeblog’s grey alder No. 1. That was on Friday the 7th of November. A week later on Friday the 14th, when I was taking photographs for the cider gums update, I saw that Bud-head (for so I called the caterpillar, after its spectacular bud-mimicking head) was still on alder No. 1. What a beaut! But when I went to check on old Bud-head a couple of days later on Sunday, it was gone. Vanished! Nowhere to be found!

What species was Bud-head? I wondered. What would it look like as a moth or butterfly? I didn’t hold much hope that I’d ever find out, after failing to identify the other caterpillars that called the grey alders home this year – see these posts from October and August. But after opening my Insects of Britain and Northern Europe Collins Field Guide, I found what I was looking for pronto. Bud-head is a Biston betularia (L.) – a peppered moth (or, when in caterpillar form, a cleft-headed looper). I was pretty impressed. Peppered moths provide one of the best-known examples of survival of the fittest – probably the most taught example in British education establishments! For those who aren’t in the know…

There are two forms or morphs of peppered moth; one light-coloured and the other dark-coloured, or melanic. Before the Industrial Revolution, most of the peppered moth population was made up of the light-coloured form. Yet once the Revolution kicked off, the dark-coloured form rose to dominance. The accepted theory puts this change down to air pollution. All of the soot and smoke kicked out by the dirty industries of Britain coated buildings and trees. The light-coloured moths used to have a good set of camouflage, but on the blackened, sooty surfaces of the Industrial Revolution they stood out like sore thumbs. At the same time the melanic form fitted in nicely; they suddenly had the superior camouflage. So while their lighter brothers were sitting ducks for predators, the dark-coloured moths thrived. Nowadays, after the decline of our heavy industries, there is less soot and smog in the air, so guess what? The lighter-coloured form is making a comeback.

I’ve just whacked all that down from memory, but if you do some digging, I’ll bet there are some good papers out there with the science to back it all up. Incidentally, judging by its colouring Bud-head is probably of the melanic form (f. carbonaria). Another interesting fact (lifted from the Collins Field Guide):

The name of the family [Geometridae] means ‘ground-measurer’ and is derived from the behaviour of the caterpillars. These are generally long and slender and they have only two pairs of prolegs… When walking they grip the substrate with the prolegs and then stretch out, as if measuring length, to find a hold with the thoracic legs. Having found a hold, they draw the prolegs up close to the thoracic ones and in doing so they throw the body up in a loop – leading to their common name of the loopers.

The Collins also adds to my light-dark story. Apparently the melanic form was first reported in 1848 (the Industrial Revolution took place around the late 18th and early 19th centuries). And:

It is believed that the larvae of the melanic form are hardier than those of the normal moths in the presence of slight air pollution – insufficient to blacken trees and walls. Industrial melanism occurs in many other moths, and in some other groups of insects as well, but in recent years there has been a noticeable drop in the numbers of melanic individuals as a result of smokeless zones in many regions.

Bud-head from behind - now probably gone off to pupate in the soil for overwintering.

Read about the peppered moth on Wikipedia.

Update (26th November 2008): I've had it brought to my attention that this post would be improved by including a picture of the peppered moth. I'll go one better and include two.

treeblog update (Set A, Day 605): grey alders & Scots pines

treeblog Set A update alert! Photography from yesterday afternoon (Day 605).

Just over a fortnight ago, as seen in the Day 590 update, the grey alders still kept most of their leaves. Yesterday it was a different story. No. 4 was completely leafless and Nos. 1 and 2 only had a couple. No. 3, weirdly, still had quite a few, while the evergreen Scots pines won't, of course, be shedding their needles. Have a good look:

Grey alders Nos. 1, 2 and 3. No. 1 and No. 2 are in winter mode, but No. 3 is holding back. Interesting.

The Beast! Grey alder No. 4, in full-on winter mode. I reckon the alders actually look better leafless than they have done for a quite a while. One consequence of all those caterpillars setting up home was the alders taking on a rather ragged appearance thanks to holes nibbled in the majority of their leaves. Some leaves were chewed right down to the main vein! Another plus that comes from leaflessness: the 3D branching structure of each alder can now be properly appreciated. Still, I’m looking forwards to seeing these guys bristling with perfect new leaves come spring.

The Alpha Scots pine. Funky needle afro. The two little rosettes up top should explode into action in the springtime.

Bark rubbing

So I went for a walk this afternoon armed with sheets of plain white paper and a blue wax crayon, and I did six bark rubbings. Over moor and under wood, it was a cold day with a clear sky. The temperature must have been close to zero as ice lingered on puddles and the ground was frozen at the top of the hill.

The bark rubbings were taken at about breast to head height on main trunks. The approximate DBH (diameter at breast height) of each tree is noted below each rubbing so as to give an idea of size and age.