Horse chestnuts and sweet chestnuts may share the same name but they aren’t related, neither are they native to Britain although they are now common trees.
Sweet chestnuts are common throughout mainland Europe and have been grown for centuries as their ‘nuts’ are edible. This is the species that people eat as roasted chestnuts. It is thought that sweet chestnuts were brought to the UK by the Romans – so in many ways they are now honorary natives. Often the tree is coppiced in Britain and the poles are used for fencing – chestnut paling. For more details see here.
Horse chestnuts are native to a small area in SE Europe and were originally called chestnuts as they were incorrectly thought to be related to sweet chestnuts. Equally odd, they were named ‘horse’ as it was thought that feeding the conkers to horses cured them of chest infections even though the conkers are poisonous to horses …… Horse chestnuts were introduced to Britain in the 1600s. More information here.
The sweet chestnut fruits inside their spiky case
Sweet chestnut leaves
The conker of the horse chestnut – every school child’s favourite tree!
The hand like leaves of the horse chestnut
Both species are found on Dartmoor – often sweet chestnut has been planted in woodlands to provide fencing posts – in the UK the nuts rarely grow big enough to roast and eat. Horse chestnuts are rarely found in woodlands but are common in hedges and parkland. Now is the time to search the ground under horse chestnuts to collect the conkers so that they can be prepared to future battles.
A friend of mine from Northamptonshire Steve Brayshaw published these pictures on Facebook on Sunday in an attempt to identify the species. It is clearly one of the shieldbugs / squashbugs (in the order Hemiptera) but it didn’t look like any of the UK species. After a bit of delving on the internet Steve identified it as a Western Conifer Seed Bug Leptoglossus occidentalis. This is a North American species which has recently invaded Europe via Italy and is now colonising the UK. It is a modest conifer pest in the US but to date hasn’t caused any problems in Europe. DEFRA have issued a fact sheet for the UK which you can read here.
Within 24 hours one of his friends on Facebook who lives in Rattery on the southern edge of Dartmoor reported finding one too – a photograph was published and the characteristic zig zags on the wing case confirmed the ID. How amazing is that!
Note the white zig zag marks on the wing cases – animal is up to 20mm in length (excluding the antennae) so is very conspicuous (Photo copyright Steve Brayshaw)
Very attractive yellow and black abdomen too (Photo copyright Steve Brayshaw)
Here is the current UK distribution (via the National Biodiversity Network) – it is obviously spreading very fast as it was first recorded in the UK in 2007. No records yet for Dartmoor but it has been recorded to the east, west and south – an of course now in Rattery!
One to keep your eyes open for – let me know if you find one! I reckon Fingle Woods has got to be a good place to look.
One of the common sights on our heathlands this autumn has been gorse bushes enveloped in huge gossamer webs. There are lots on Piddledown Common and below Castle Drogo on the heath in the Teign Valley for example. These webs are made by tiny animals known as gorse spider mites – each mite is bright red and is less than 0.5mm in length but they live in large colonies.
It beggars belief that these tiny animals can make such huge and complex web
The gorse spider mite has been taken to New Zealand where it is used a a biological control to get rid of gorse which has been introduced to those islands and has become an invasive weed in some places. In Devon and on Dartmoor despite the large number of spider mite webs I would say the gorse still has the upper hand ……
As we move into autumn it suddenly becomes time again to start the 10 Tors training cycle all over again! We started the process yesterday with a group of year 9 students teaching them the basics of map reading and navigation. We based ourselves around Haytor and Hound Tor – so not big distances but lots of opportunity to learn how to take a bearing and go in the right direction!
Here is a group at Hound Tor looking back to Haytor
It may have been an overcast day but the moor was pretty busy – here is a group of novice climbers at Hound Tor
This is the Becka Brook between Haytor and Hound Tor – very low river levels so an easy river crossing!
One of the quarries around Holwell Tor
The remains of the old quarry tram way tracks
Back to the car park via Haytor
Four of this year’s foals at the Haytor visitor centre car park.
A successful day with a group of enthusiastic students – bodes well for the coming months!
If you want a good introductory walk to Dartmoor I can recommend a gentle walk from Haytor to Holwell Tor, over the Becka Brook to Greator Rocks and then up to Hound Tor – its around 2.5 miles (each way) and as long as the visibility is good you can see exactly where you are aiming for and where you have come from. A great walk to practice map reading and gaining your moorland confidence.
Over the past couple of weeks there have been large numbers of daddy long legs about. They have been in my house near Exeter and up on the high moor on Dartmoor.
‘Daddy long legs’ are also known as craneflies – there are over 90 different species. This individual has a blunt abdomen – meaning it is a male
This one has a pointed abdomen – its a female. Craneflies on Dartmoor provide an important food source for various birds such a dunlin and meadow pipits
The species that is so numerous at present is Tipula paludosa. Looks a bit like something out of Star Wars!
Here is a close up – flies only have a pair of wings (bees have two pairs) in this picture you can see a stalk with a blob on the end below the pair of wings. This is known as the haltere – it is used rather like a gyroscope to help flies fly – it is also the ‘second’ pair of wings – all flies have halteres instead of the second pair of wings.
I suspect that everyone at some point has become entangled in a bramble! Fewer people are aware that not all brambles are blackberries. There is another pretty common bramble in our countryside too – the dewberry. Now autumn is here and the fruits are present it is much easier to spot dewberries and tell them apart from blackberries.
This is the blackberry – a vey familiar sight. The stems are covered in strong prickles which can easily cut our skins.
Here is the fruit of the dewberry – superficially similar to the blackberry but a more frosted blue. The prickles on the dewberry are not as dense or as fierce as those on the blackberry.
Worth keeping your eyes open in Dartmoor’s woods for the dewberry – they are also pretty common on the coast especially on sand dunes. Unfortunately dewberries don’t taste very good – they are much more tart than blackberries – probably the reason I guess that most people have never heard of them.
Sharp Tor in the Teign Valley near to Castle Drogo is a popular and well visited Tor. It is easy to get to and find as it is not on the high moor in the middle of nowhere! It is on the route of one of Dartmoor’s most popular walks ‘The Teign Valley Classic‘. This walk starts at Castle Drogo and heads towards Fingle Bridge and then loops back along the river and up to Drogo again. It is around 5-6 miles long and does involve going up and down at bit but it is a brilliant walk giving some of the best views in England. Highly recommended and perfect as an autumn walk.
Sharp Tor from Hunter’s Path
The birch leaves are turning brown and beginning to fall
It’s a good sloe year