Tuesday, 28 June 2016

Tasty bark

It's been a bit of a race trying to protect as many of the emerging oaks and beech as possible before they are eaten by deer. We've protected 75 so far with our recycled tree tubes and home made stakes. We have to be fast. A seedling beech was marked  with one of our red painted stick markers but not covered immediately.  Returning to it a short time later with a tree tube and stake, it had already been been eaten - stripped of its foliage leaving a bare twig behind.  The other day Sarah looked up from banging a tree stake in, to see a heavily pregnant doe staring at her through the bracken. A quick snap with a mobile phone got a picture of the culprit. The deer at this time of the year are usually single does.

Though the deer browse a great deal at ground level, they also tear off and eat tree bark. However they do not appear to cause such  excessive damage that squirrels wreak on trees, particularly beech. This summer has been particularly bad.  The mild winter of 2015 - 2016, with plenty of available food and seemingly no need to hibernate,  appears to have led to a squirrel population explosion. We've never seen so much damage to our beech trees. They rip the bark off from the base to the top of the tree, seeking the sweet layer directly under the bark. We have  tried protecting  trees from deer,  by piling  branches and other brash around the tree stem. Though this seems to have some deterrent effect, nothing stops the squirrels. who just climb further up the tree and start stripping the bark there. The effect of  this is to slow the growth of the tree, and if it is so bad that the bark is stripped off all round the trunk - effectively ring barking it -  then the tree will die.

The culprit  of this vandalism is not the small pretty, native  red squirrel (sadly now only found in isolated pockets in the UK) but the larger, immigrant American grey squirrel  (Scirius caroliniensis) These are  native to North America and were first released in the UK in 1876 in Henbury Park Cheshire. They soon spread throughout the country.

Red squirrel (library picture)
Unfortunately they have had a devastating , and well documented effect on our native reds which can now only be found in a few areas of the British Isles. However, to be fair , although they are bigger and have a reputation for being aggressive, they do not kill red squirrels and there is some evidence that red squirrels were already on the decline before the greys turned up, because of habitat loss and disease. So it may be argued that the greys just took up the space vacated by the reds.  The grey's success, (there are about 66 greys for every red) seems to be down to their being better at competing for food. They are also prolific breeders with 2 litters a year of between 3 and 7 'kits'. This is why some extermination programmes have not worked - clear the greys out of one area and neighbouring colonies just move in. In addition, they carry the squirrel pox virus which while it doesn't harm greys, is a serious infection for red squirrels.

We  wondered if it might be possible to paint some sort of a deterrent  on the tree trunks, but it seems not. It would be wonderful if both the deer and squirrels stuck to eating birch, bracken, bramble and grass. There's plenty of that to feed them , and would  make our work so much easier.  However, like us,  it seems that  both animals like a varied diet, and the cambium layer which lies underneath the bark is a great treat for them.  Bark stripping is at its height  from April to July, and after this the activity falls off markedly., and the tree will have some months to try and repair the damage. Once the tree grows larger, squirrels lose interest. So, if pest control doesn't work, though that's something we will try, it looks as if we'll just have to live with it, and hope that we can grow enough  beech trees , healthy enough to resist grey squirrel damage.

Sometimes, this sort of dispiriting  battle with woodland pests can make the  restoration of  30 acres of woodland feel like an uphill struggle. We  put in two regular working days a week at Old Copse  throughout the year,  and are fortunate to have occasional help from our deer stalkers, and  a volunteer or two. We also make good use of child labour when it is available. Bracken bashing is an excellent job for kids - an easy ,  light and satisfying  activity with instant results. So, it's important to remain optimistic, and to remind ourselves of what we've  achieved during the past 7 years, despite all the difficulties, and  appreciate how much our hard work  has transformed Old Copse.

Latest sightings: fallow deer (see above), a pair of wrens with 3 fledglings,  making good use of a brash pile to raise their young family, a pair of marsh tits, 4 speckled wood butterflies on the bluebell walk,   many bees busy in the alder buckthorn.

Alder buckthorn in flower - a bee magnet

Tuesday, 7 June 2016

Learning as we go: business as usual at Old Copse

One of the items in our 5 year plan for Old Copse 2 (i.e. a second block of 15 acres, purchased in January 2013) was, by way of an experiment,  to clear fell an acre or so in the birchwood. The birch, being a pioneer species, rushed into the space cleared by the 1987 storm  that knocked down the then 30 year old scots pine plantation. We originally planned to replant this area with a variety of broadleaves . But as we grew to know this bit of the wood better, we saw that it was in fact surprisingly diverse, rather than just a birch monoculture. The birch have acted as 'nurse' trees, protecting a good number of flourishing young oak, beech, rowan, cherry, sweet chestnut etc. So, happily, we don't need to clear fell, which in any case would only mean an inrush of intractable bracken, as we've seen elsewhere in the wood. Instead we will give the young broadleaves more light and space by carefully 'halo' thinning around them.

The new track/bluebell walk through the birchwood entailed quite a bit of  felling to allow machinery through during the Scots Pine thin of late 2015. This newly cleared space has already created a wildlife corridor for a growing number of birds and butterflies that use it as a short cut through the wood and feed on the plants on the sunny edges. It is extremely gratifying to see how quickly wildlife spots an opportunity. We will continue to widen this corridor, pollarding the birch along its edges and planting  home grown hazel  underneath. This track is not in full sun all the time, but has dappled shade at different times of the day, along its length. We think this variation in light and shade has prevented the dreaded bracken from taking over.

The deer are back, especially does with their young. Having mostly disappeared, to the deer stalkers frustration, during the winter and early Spring months, they soon learned that it is now closed season for doe shooting.  There is plenty of  evidence of their return, especially around the car-park where the flattened grass attests to their enjoying the  morning sunshine. The stag season begins in August, so they have a respite of a couple of months in which to snack on everything the wood offers. The Spring and early Summer weather -  warm sunshine with regular periods of rain -  has resulted in lush growth, so perhaps the deer will be content with grass rather than seedling trees. Hmm, wishful thinking perhaps, so we've been continuing to protect emerging trees, primarily oak and beech. We've covered 64 so far. We only expect a proportion of these to survive, so in addition, next  autumn/winter we will be planting our homegrown Old Copse transplants - about 50 have been successful, augmented with bought in tree 'whips' from a nearby tree nursery. Our aim is a minimum of 200 seedlings and new planted trees in Old Copse by the end of next winter.

Last week was half-term so children were in the wood amusing themselves with axes and knives. This might sound dangerous, but with the right instruction they soon learn how to handle these tools safely. They gained, I think, a good sense of achievement and satisfaction by chopping kindling for the log burner, making a new swing, and carving spoons.
Practising with the axe
Spoon whittling