Category Archives: woodland

Deer and reforestation

The moist and mild climate of Ardnamurchan provides almost ideal conditions for the germination of plants and trees. Wherever you walk, if you look carefully, you can find miniature birch, diminutive rowans or little oak trees.

Birch seedling

Parts of the peninsula have extensive broadleaved woodland and the area is famous for its oakwoods around Salen and Ariundle. We have hazel copses, a large amount of willow and alder carr, some grand old oaks and lots of birch.

Or lots of rhododendron, depending where you look, though it is gradually being cut back.

Mixed established deciduous woodland has excellent biodiversity and oak trees are famed for having more associated species of wildlife – including bacteria and fungi, lichens, free algae, mosses, vascular plants, invertebrate animals, birds and mammals – than any other tree in the UK.

Oak, late November

However, unfortunately, it’s true to say that on Ardnamurchan – and in lots of other places in the Highlands – mighty oaks from little acorns do not grow 1.

The missing generation

It’s easy to find seedlings a few inches high and the mature trees are obvious. What’s missing, or at least significantly under-represented, are saplings and small bushes.

For example, we have two or three rowans (mountain ash) close by the house. All are mature trees (~15+ feet tall) laden with berries from late summer onwards. All spring and summer I’ve been finding 3-5″ tall (short?) rowan seedlings, perfect in everything but stature.

But there are no rowans on the plot that are waist or head height.

It’s all, or almost nothing.

Well, not quite. You can find these missing generation(s) of spindly saplings growing from cracks in steep rock faces or other inaccessible spots.

You can also find a few shin-high, multiply-branched, twiggy, de-leaved, stunted specimens. These often have fat little trunks and extensive root systems, out of proportion to the tree height, like a poor quality bonsai.

Browsed rowan

The grim reaper

The inaccessible saplings and the thick-limbed but dwarfed individuals give an obvious clue as to the fate of the missing generation.

They are being, or have been, browsed to extinction.

There’s no regeneration of native woodland because as soon as a tree is tall enough to be noticed it’s a midnight snack for deer.

On very steep slopes the deer cannot graze so the saplings escape. However, there’s often little soil present, or the ground is unstable, or it dries out too much, so the tree never reaches maturity.

Accessible saplings get grazed and grazed again. The new juicy growing tips are nibbled away, leaving ever-thickening twiggy branches. Year after year this results in a stunted, distorted little bush, with lots of woody growth but few leaves.

Too much of a good thing

There are six species of deer in the UK – red, roe, fallow, sika, muntjac and Chinese water deer. Of these, the first two are native to the UK with the rest being imported. However, fallow deer were here before the last ice age and were re-introduced after the Norman Conquest (11th Century).

Red and (particularly) roe deer are widespread and, in places, common.

Deer … they’re everywhere

Too common.

In Scotland, red deer densities (PDF) can be greater than 30 per km2 in places, with very high levels in the Grampians and north and west of the Great Glen.

It is estimated that the current red deer population in Scotland is in excess of 450,000 head. This number has increased at least three-fold since 1959 when The Deer (Scotland) Act was introduced in response to a growing awareness of the damage to agricultural crops and native woodland.

In 1959 the recommendation was that an optimum number of red deer in Scotland was ~60,000. ‘Optimum’ in terms of reducing crop damage and allowing natural reforestation without ugly and expensive fencing.

Presumably not ‘optimum’ in terms of animals available for stalking. Which is a significant part of the problem …

Simon Pepper (ex-WWF Director for Scotland and Deer Commission) has written a brief account of “the deer problem” in Scotland and Reforesting Scotland nicely describe the impact and management of deer. I won’t rehash the case they make here but I think it’s compelling.

The camera never lies

Our plot is not fenced and deer regularly come down off the hill or out of the surrounding woodland. I occasionally spook them when I’m wandering about clearing rhododendron or birdwatching. At night their visits become more frequent … we might not see or hear them but the dog detects them with her ultra-sensitive radar and growls quietly.

They trample regular ‘game trails’ across parts of the plot, moving from one block of woodland to another during the night, or going down to the shore.

I’ve positioned a trail cam in likely looking spots and regularly ‘see’ red deer and, about 10-fold less frequently, roe deer. Whether this reflects the population density of the two species or is a consequence of the locations used for the camera is unclear.

It’s very common to ‘see’ a red deer hind with a calf in tow. Stags are a lot less frequent.

At times they descend from the hill mob-handed, late in the evening, intent on the destruction of almost everything except rhododendron (which unfortunately they don’t eat due to the grayanotoxins in the leaves).

Reforestation and stalking

It’s ironic that deer are woodland animals, yet their presence in large numbers prevents the regeneration of the forests in which they should flourish. Red deer from open moorland are smaller, less well conditioned and have higher winter mortality than woodland deer.

Inevitably, large scale culls have been unpopular with the general public and the landowners who provide stalking.

Importantly though they have been effective. They have reduced the numbers of deer on the land and have allowed the natural regeneration of forest without the need for fencing (which brings its own problems).

Richard Baynes has written about the consequences of the deer cull in Glen Feshie, both in terms of the uproar in the shooting community and in the resulting improvement in reforestation. The income from stalking is the same now as before the cull; clients are “prepared to pay more to hunt a scarcer, wilder animal”.

For a more extensive discussion of reforestation and biodiversity, accompanied by outstanding photographs, I recommend you have a look at Alan Watson Featherstone’s blog.

Solutions

I love deer.

Particularly braised slowly with a good quality, full-bodied red and winter vegetables 😉

However, I don’t like venison so much I could make a serious dent in the local population of deer.

Therefore, other measures are needed to deter deer and to encourage the regeneration of trees. In turn this will decrease the triffid-like invasion by rhododendron and increase the native wildflowers and understory vegetation.

Deer fencing remains an option but is unsightly, expensive and – because of access issues  – would require gates and/or cattle grids. Properly maintained it is the only certain way to exclude deer.

Lion dung has proved tricky to source, but may not be effective anyway.

I’ve planted a few tree seedlings ‘rescued’ from inaccessible areas, together with a dozen or so willow ‘sticks’ to provide early season pollen for bees. Several of these have already been decimated by the deer.

Transplanted rowan seedling

I’ve therefore protected some with mesh tree guards to help them get well-established.

I’m intending to plant another hundred or so bareroot native trees this autumn. Rather than littering the plot with dozens of unsightly corrugated tubes I’m hoping to exploit the topography to barricade access points, only putting tree guards around the saplings on the periphery. Additional temporary fencing will be added where needed if the barricades alone prove to be ineffective.

Willow cutting with tree guard

Or when … 🙁


Notes

Laga Farm on Ardnamurchan has a large fenced area of hillside overlooking Laga Bay in which native trees have been planted. The sparse woodland is only six years old but is already developing really well and is wildlife-rich … and will undoubtedly get better. In addition to the planted trees there is also a large amount of natural tree regeneration now that the deer are excluded.

Laga Farm Native Woodland

Are you sitting comfortably?

The heady combination of hills, lochs and ever-changing light make for some wonderful views on Ardnamurchan. This is obvious from some of the dawdling rubberneckers on the tortuous B8007. Far better to stop and take in the view properly than to drive with one eye on the scenery and one on the next blind corner.

And once you do stop it’s good to sit.

Isle of Carna, Loch Sunart

Relax. Why rush?

And the same applies when you reach the end of your journey.

Sometimes I sits and thinks, and sometimes I just sits

Our plot is south-facing, partly wooded and heavily overgrown with rhododendron. However, between the trees and over the rhododendron there are some great views of Loch Sunart, the hills of Morvern and – looking north and west – the Ardnamurchan hinterland.

It’s good to sit and watch the world and the wildlife go by, to see the yachts and fishing boats on the loch and to listen to the birds and the wind in the trees and … little else.

You can sit and think things through, or just sit 1

But don’t rely on being able to sit on the ground. The climate in Ardnamurchan is mild and wet. At times very wet. The annual rainfall exceeds 1700mm and so the ground is often damp.

So you’ll need a chair, or a bench or a thoughtfully-placed log.

Sometimes I sits and thinks, and sometimes I just sits

Having carried a collapsible chair around the plot a few times it was clear where the likely spots were to place a more permanent seat.

Now all I had to do was find some suitable wood.

Larch

Totem pole

Did I mention it can be wet in Ardnamurchan? Anything left out in all weathers needs to be rot proof. Teak is the obvious choice but I’d prefer not to contribute to the further destruction of Myanmar’s tropical forests.

Something closer to home was needed.

Aside from the ubiquitous birch, rowan, hazel and oak there are a number of larches around the site. One of these had been topped and limbed (albeit rather crudely).

It was a favourite spot for the greater spotted woodpecker but it was also a bit of an eyesore.

It intruded into some of the better views and looked like a totem pole. I even briefly considered tidying it up in situ and producing some chainsaw garden sculpture from it.

Instead, I felled it.

It was growing from a very steeply sloping bank and necessitated a rather precarious stance, but the combination of my Trusty Husky and a plaid shirt soon had it down.

Larch (Larix decidua) is a deciduous conifer introduced to the UK in the 17th Century 2. The needles turn a lovely yellow in autumn before being dropped and are then replaced with fresh, bright green growth the following spring.

There are two other notable things about larch. In my experience it generates some of the smallest and most irritating splinters when freshly cut. Gloves are essential. More importantly, it exhibits good resistant to rot, so was ideal for my purposes.

Ardnamurchan chainsaw massacre

The tree was about 35 years old and far too heavy to move without some more attention from the chainsaw. Having properly tidied the side branches protruding from the ~6-7 metre trunk I cut it into suitable sized logs. Then, using a combination of brute force and lashings of ignorance, I manhandled them to a flat area to construct some log benches.

Larch garden bench

You weren’t expecting fine furniture were you?

Having created a couple of notches in the trunk I rested it on two cut logs and then levelled the top off to create a flat area to sit on. The resulting bench was very sturdy, pretty stable and exceedingly heavy. It also left me with half a dozen infuriatingly small and itchy splinters …

Little and Large

Having made one I then made a second slightly smaller log bench with the ‘leftovers’.

Location, location, location

I made two log benches as I’d already identified two positions with contrasting and rewarding views.

The first was on a rocky outcrop backed with light woodland, which commanded good views to the north west. It’s relatively sheltered from the east and is in dappled shade until the afternoon.

Somewhere to sit and think

I managed to carry the smaller bench up to the rocky outcrop unaided, with several rests to breathe look at the view.

The larger bench was much too heavy to lift and was to be located further away and – critically – further up the hill. So, having chosen to install it on the warmest part of a sunny June day (D’oh!), I laboriously lifted it, end-over-end, up and up and up the hill.

About an hour and three pints of sweat later I’d got to the top having inadvertently discovered a wasps nest in the undergrowth. They didn’t take too kindly to me thudding past with my carefully handcrafted bench.

But it was worth it …

The perfect place for a cup of coffee or glass of wine

There are panoramic views over the islands (Risga, Oronsay and Carna) in Loch Sunart, the hills of Morvern to the south, and to Ben Hiant, Mull and Coll to the west.

Time for a rest …


Notes

The splinters that freshly-cut larch generates are very quickly rubbed away and the benches are perfectly safe to use without wearing gloves (or reinforced trousers).

A good guide to tree identification is Collins British Tree Guide (ISBN 978-0-00-745123-4) by Johnson and More. For more information on the propagation, growth, uses and lore of Scottish trees I recommend A handbook of Scotland’s trees (ISBN 978-190864382-7) edited by Fi Martynoga.

If you want to know what you can see from any point on earth I recommend the HeyWhatsThat horizon plotter website. Quoting directly from the site this computes the horizon and mountain names and other related visualizations, including the surface of the Earth visible from where you’re standing (the visibility cloak or viewshed) and the line of sight profile between you and the distant peaks”.

For example, here’s the map of what’s visible from the top of Ben Hiant …

HeyWhatsThat horizon map from Ben Hiant, Ardnamurchan

 

Don’t forget your roots

Having discussed the Triffid-like rhododendrons that infest parts of Ardnamurchan and the tools needed to clear them, here’s a further instalment showing how to ensure they don’t re-grow.

Rhododendron (Rhododendron ponticum) are relatively shallow-rooted woody shrubs. They can spread by wind-dispersed seed and by suckering. Suckers are more correctly termed basal shoots and emerge from the root system.

Dense rhododendron growth with no understorey

Dense rhododendron growth with no understorey

Each of these suckers essentially has the ability to form a new plant.

If you cut a rhododendron to near ground level – leaving just enough of the woody stump to trip over 🙁 – it will usually produce new growth.

Even if it doesn’t produce growth from the stump, it will almost certainly generate suckers from which large new plants will eventually grow.

Consequently, simply cutting rhododendrons to the ground and leaving the roots untouched results in dense multi-stemmed thickets forming.

Multi-stemmed rhododendron from suckering

Multi-stemmed rhododendron from suckering

Therefore to ensure the rhododendron does not re-grow you must kill the roots of the plant. There are a variety of methods that can be used to achieve this, some faster than others.

Environmentally friendly methods – efficacy unknown

You can cut and clear the rhododendron and then periodically return to the stumps and, using something like a hammer, smash down the re-growth. Over a period (perhaps a long period) the stump will be killed.

There is an approach called the ‘lever and mulch’ method in which the shrub is cut down and the amputated top growth is used to cover the stump, effectively starving any new growth of light.

I’ve not tried either of these methods – I don’t have the time and want the site cleared – and so cannot comment further on them.

Environmentally unfriendly methods

A very common approach is to cut down the plant and then return after it has re-sprouted to spray with a systemic weedkiller such as glyphosate (in commercial products Roundup or Gallup).

Spraying requires a dry relatively calm day. If it’s wet and/or windy the weedkiller will either be less effective or may damage other plants.

Ardnamurchan has fabulous weather but it’s not always suitable for spray treatment 😉

I’m also not keen on the relatively indiscriminate application of weedkillers so have not used this method.

Drill and drop

What’s needed is a method that applies a weedkiller such as concentrated glyphosate in small amounts precisely where it is needed.

This can be easily achieved using stem injection.

The method is simplicity itself. A 10mm hole is drilled near the base of the trunk and 1-2ml of strong weedkiller is applied directly into the hole. The weedkiller is transported throughout the plant and, over a period of weeks or a few months, the plant is killed.

Once the plant is dead it can be cut down and burnt.

For pretty-obvious reasons this method is known as drill and drop.

Birds-eye view of a multi-stemmed rhododendron drilled for glyphosate application

Birds-eye view of a multi-stemmed rhododendron drilled for glyphosate application

Notice the holes an inch or two above the leaf litter in all the major stems. Why, if ‘… the weedkiller is transported throughout the plant …’ does every stem have to be drilled?

That’s because I oversimplified the method. The weedkiller appears to only kill the top growth and root of the individual sucker. It’s not entirely clear why. I presume that the new growth establishes its own root system over time (some of these stems are 2-3″ in diameter and 15-18 feet long) and that the weedkiller only spreads systemically within this new growth.

Consequently every stem must be drilled … and some will be missed 1.

Therefore, there is another method that can be used …

Drop and drill

You cut the plant down first, drill the remaining stump and apply the weedkiller. This approach has the advantage of immediacy. There’s no waiting for the rhododendron to die. It also has the advantage of thoroughness. Since you’ve cut all the top growth down you cannot inadvertently miss any of the stems.

Drop and drill

Drop and drill

The additional advantage is that you are generally drilling from the top into the stump. It’s easier to generate a clean hole and there’s even less chance of spilling weedkiller.

Driller killer

A battery-powered portable drill with a 10mm wood bit is needed. If the rhododendron growth is very dense or very extensive or – in my case – very dense and extensive 🙁 then it’s worth having a spare charged battery or two so you aren’t forced to stop just as you’re beginning to have fun.

The hole needs to be 2-5 cm deep. It is best drilled at an acute angle to reduce the chance of excess weedkiller running down the stem onto other plants. One hole is generally sufficient, even for the largest stems.

Stems as narrow as 2 cm in diameter can also be drilled. Choose a place where the growth is horizontal – close to the original stump – and drill a 1 cm deep hole, filling it with weedkiller to just below the brim.

Choose your poison

The weedkiller I use is Gallup glyphosate. Bought in bulk this costs about £20 for 2 litres. Because you’re applying a very small amount to a single, potentially very large, plant it needs to be used quite concentrated. I’ve used it at 20-25% i.e. mixed 1 in 4 or 1 in 5 with water.

Prepare a stock solution in a well-labelled plastic bottle. Don’t make up much more than you need as I’ve read it degrades over time and so loses efficacy. I make up 250ml which is enough for a very rewarding afternoon of rhodo-poisoning.

Trickle 2 container for delivery of glyphosate

Trickle 2 container for delivery of glyphosate

Administering 1-2 ml to a small hole in the base of a drilled stem requires a steady hand and a bottle with a nozzle that doesn’t drip or leak. I’ve used what a beekeeper would know as a Trickle 2 oxalic acid bottle. These probably have a proper name, but I’ve no idea what it is.

The bottle has a 100 ml reservoir and a small upper chamber that takes 5 ml. It has a twist-lock nozzle and doesn’t drip. It needs to be refilled every 50 or so stems. Remember you’re probably using it on your hands and knees in dense undergrowth. A refill is a welcome opportunity to stand up and stretch.

Drill and drop vs. Drop and drill

In practice I’ve found I have to use a mix of the two approaches. Each has advantages and disadvantages, but both are usually needed.

Drill and drop is great because the killed shrubs are much lighter to cut down, easier to transport and burn faster. It takes about 3 months for the plants to die – the upper growth withers and finally drops off.

The disadvantage of drill and drop is that you need to get to the base of the stems in very heavily-overgrown areas. Almost inevitably this means crawling about, working in confined dingy spaces and involves encounters with brambles, wasps nests and sharp pointy things.

Wear safety glasses.

New growth retrospectively drilled and killed

New growth retrospectively drilled and killed

Almost inevitably you’ll miss some stems. Drop and drill has the advantage of immediacy. You cut the plant down and then drill and poison the stump. You gradually work your way through a dense thicket, but the drilling and glyphosate delivery is done in an already cleared area so is much easier.

Slash and burn

I prefer to drill the plants, let them die back, cut them all down and return to ‘mop up’ the remainders I missed the first time round. I usually carry a pen to mark stumps cut down ‘live’ that need retrospective treatment 2. This avoids double-dosing.

If you cut the trunk near but below the previously drilled site the woody interior of the stem is usually stained distinctively, so you can avoid re-dosing it.

Waiting for the inferno

Waiting for the inferno

The side branches and top growth are removed with a billhook, stacked up and subsequently burnt.

Towering inferno

Towering inferno

The main stems are cut up and dried for firewood.

Something for the winter

Something for the winter

That lot is about half what I prepared from the 1600 m2 (i.e. 40 m x 40 m) area I’ve cleared so far.

Glyphosate – mode of action and toxicity

Glyphosate is a broad-spectrum (i.e. indiscriminate) weedkiller that inhibits the plant enzyme 5-enolpyruvylshikimate-3-phosphate synthase. This enzyme is critical for the synthesis of the aromatic amino acids tyrosine, tryptophan and phenylalanine. Production of these amino acids is important during plant growth which explains why glyphosate only kills growing plants.

Glyphosate was discovered by Monsanto, given the trade name Roundup and first used for agricultural purposes in 1974.

It is adsorbed through the leaves, through drilled or cut stems but only poorly through the roots. Stem drilling, or stem injection, is a much more effective way of administering glyphosate than simply painting it onto a cut stem; there is less wastage and much less potential for collateral damage.

Glyphosate has low acute toxicity and a half-life of about 47 days in soil.

Glyphosates and cancer

Glyphosate is extremely widely used. Consequently, residual amounts are sometimes found in food products. The levels are very low, with over 99.5% of nearly 7000 food products tested in 2016 having less than the maximum allowed residue levels.

However, the very widespread use and potential long-term exposure to low levels of glyphosate mean that it has repeatedly been associated with causing human cancers. Monsanto (now Bayer) have recently lost a court case when sued by a an individual who had developed non-Hodgkin lymphoma, claiming it was caused by long-term exposure to high levels of glyphosate while working as a gardener. Monsanto is appealing against the decision.

The scientific evidence (a very different level of ‘proof’ to a law court) supporting glyphosate being a carcinogen is very limited and equivocal.

A long-term (decades) study of 55,000 people showed that there was no increased risk of cancer in those exposed to higher levels of glyphosate.

Very recentlymeta-analysis (a statistical study of other studies) has linked exposure to very high levels of glyphosate to non-Hodgkin lymphoma. Despite the headline figure being a scary 41% increased risk 3 of developing non-Hodgkin’s lymphoma the absolute risk was only about 0.5%. And this was only for people exposed to very high levels over a very long period.

The headline 41% figure sold some newspapers, but the coverage was probably distorted and ignored or selectively over-interpreted much of the scientific evidence.

There’s wasa good account of this subject on the More or Less podcast recently.

Nevertheless, I always take care when using glyphosate. I wear disposable nitrile gloves and safety glasses. I administer small doses (1-2 ml) to the drilled holes, avoid spilling it and wash my tools and hands carefully after use.

A blank canvas

Before

Ardnamurchan or Borneo?

Ardnamurchan or Borneo?

After

Cleared and ready for native tree planting

Cleared and ready for native tree planting

There’s still more to do (measured in acres not m2) but after a bit more clearing this area will be planted up with native trees in the 2019/20 winter.