Nobby’s blog 9/9/17
New recruits at The Academy this week. We had five existing potential apprentices and then selected another four on Thursday.
It was then on to the employer interviews, which took place on Friday. It was good to see that so many of the interviewees wanted to make an impression, and in addition to wearing suits and ties, had researched their potential employers. Always a good idea to go into any interview, with some background information about the people you are talking too.
Many thanks to Julian Montague from Glendale and Tom Purchase from KJ Thulborn for spending the day chatting with the apprentices. We are all now waiting to see which candidates were successful, and which employer makes them an offer…..FINGERS CROSSED!!!
FOCUS on………. Oak Identification
Oaks have about 600 species in the world. We have two native oaks in this country, Quercus robur, and Quercus petraea. Quercus robur is also known as English oak or pedunculate oak, and Quercus petraea is also known as Durmast, or more commonly sessile oak. Until the 1700’s they were both treated as one species of tree, until both someone had the good sense to look a bit closer at the differences.
You would think it would be easy to tell them apart- well…..
New recruits at The Academy this week. We had five existing potential apprentices and then selected another four on Thursday.
It was then on to the employer interviews, which took place on Friday. It was good to see that so many of the interviewees wanted to make an impression, and in addition to wearing suits and ties, had researched their potential employers. Always a good idea to go into any interview, with some background information about the people you are talking too.
Many thanks to Julian Montague from Glendale and Tom Purchase from KJ Thulborn for spending the day chatting with the apprentices. We are all now waiting to see which candidates were successful, and which employer makes them an offer…..FINGERS CROSSED!!!
FOCUS on………. Oak Identification
Oaks have about 600 species in the world. We have two native oaks in this country, Quercus robur, and Quercus petraea. Quercus robur is also known as English oak or pedunculate oak, and Quercus petraea is also known as Durmast, or more commonly sessile oak. Until the 1700’s they were both treated as one species of tree, until both someone had the good sense to look a bit closer at the differences.
You would think it would be easy to tell them apart- well…..
00’s they were both treated as one species of tree, until both someone had the good sense to look a bit closer at the differences.
You would think it would be easy to tell them apart- well…..
Quercus petraea (Sessile oak)
When you look at the picture of the sessile oak above, there are two main things to look at. Firstly the way the leaves and acorns are attached to the twig, and the shape of the bottom of the leaf.
If you look closely, you will see that the leaf has a short stalk (petiole), but the acorns have no stalk and are fused directly on to the twig.
However…….
…. take a look at this-
You would think it would be easy to tell them apart- well…..
Quercus petraea (Sessile oak)
When you look at the picture of the sessile oak above, there are two main things to look at. Firstly the way the leaves and acorns are attached to the twig, and the shape of the bottom of the leaf.
If you look closely, you will see that the leaf has a short stalk (petiole), but the acorns have no stalk and are fused directly on to the twig.
However…….
…. take a look at this-
Quercus robur (English oak)
Look at the English oak above and compare the two pictures. The leaves have no stalk (petiole) attaching them to the leaf, but the acorns are on a short woody stalk called a ‘peduncle’ hence pedunculate oak. If you also look at the base of the leaf, there are two projections that wrap around the base, called ‘auricles’. They are marked by the red arrow. Auricle means something that looks like an earlobe (or ear), and you can see them clearly in this image.
I found these two specimens within 100m of each other. On Dartmoor, we tend to find higher concentrations of Q. robur as standard trees in fields and in some remaining stands of high altitude oak woodland ( there are only three left), such as Wistman’s Wood. Sessile oak tends to frequent the river valleys. It is thought that Q. robur colonised first after the retreating ice, followed by Q. petraea which tends to prefer it slightly warmer, and that may explain the curious pattern of oak distribution.
Although these two specimens seem to be pretty representative of their species, it is also possible for them to hybridise, producing a lot of intermediate forms. Don’t worry too much if sometimes you find auricles on trees with no peduncles on the acorns, or slightly longer or shorter petioles on the leaves- it can be bewildering!!
The timber qualities of both species are similar, but Q. robur is thought to have more curved branches, making it more favoured for ship building.
There are many majestic and ancient oaks in Britain, this one on the left below, is one I went to see in Windsor Great Park, on a tour with legendary tree geezer Ted Green. It is gnarled and propped, but in rude health. It is called King Offa’s oak and is thought to be around 1300 years old
Look at the English oak above and compare the two pictures. The leaves have no stalk (petiole) attaching them to the leaf, but the acorns are on a short woody stalk called a ‘peduncle’ hence pedunculate oak. If you also look at the base of the leaf, there are two projections that wrap around the base, called ‘auricles’. They are marked by the red arrow. Auricle means something that looks like an earlobe (or ear), and you can see them clearly in this image.
I found these two specimens within 100m of each other. On Dartmoor, we tend to find higher concentrations of Q. robur as standard trees in fields and in some remaining stands of high altitude oak woodland ( there are only three left), such as Wistman’s Wood. Sessile oak tends to frequent the river valleys. It is thought that Q. robur colonised first after the retreating ice, followed by Q. petraea which tends to prefer it slightly warmer, and that may explain the curious pattern of oak distribution.
Although these two specimens seem to be pretty representative of their species, it is also possible for them to hybridise, producing a lot of intermediate forms. Don’t worry too much if sometimes you find auricles on trees with no peduncles on the acorns, or slightly longer or shorter petioles on the leaves- it can be bewildering!!
The timber qualities of both species are similar, but Q. robur is thought to have more curved branches, making it more favoured for ship building.
There are many majestic and ancient oaks in Britain, this one on the left below, is one I went to see in Windsor Great Park, on a tour with legendary tree geezer Ted Green. It is gnarled and propped, but in rude health. It is called King Offa’s oak and is thought to be around 1300 years old
The one on the right is of similar age, and in the same group. These old trees are a magnificent link to our past, and support vast quantities of wildlife due to their longevity. They require special care and management, to maintain their structures sometimes, as this one shows.
… and talking of oaks as habitat, here is an unusual object I found on the sessile oak specimen, when I was taking the pictures. It is called an Artichoke Gall. It is created by a tiny wasp called Andricus foecundatrix. The wasp lays its eggs in a leaf bud, and then the insect hijacks the trees own chemistry to make a home and food source for itself, by making the bud grow out of the control of the tree, and into this distinctive shape. There are many types of gall wasps, and they all have distinctive shaped galls, which are on buds, leaves, flowers or acorns. This one takes its name from the similarity to an artichoke (pictured right) image courtesy of:
https://previews.123rf.com/images/levkr/levkr1208/levkr120800017/14654873-Ripe-green-artichoke-isolated-on-white-background-Stock-Photo.jpg
https://previews.123rf.com/images/levkr/levkr1208/levkr120800017/14654873-Ripe-green-artichoke-isolated-on-white-background-Stock-Photo.jpg
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