0:00:28 > 0:00:31It's early spring at the moment.
0:00:31 > 0:00:34It seems fairly quiet. A few walkers going through,
0:00:34 > 0:00:37but what is actually happening here at the moment?
0:00:37 > 0:00:41Well, I suppose the woodland itself is coming out of its winter sleep.
0:00:41 > 0:00:43The ground floor of the woodland flowers
0:00:43 > 0:00:44are a bit early for them yet.
0:00:44 > 0:00:48They'll start to develop because the woodland canopy hasn't fully developed.
0:00:48 > 0:00:51Natural light is getting in for them to sprout and develop.
0:00:51 > 0:00:54Within a month's time, this will be awash with colour,
0:00:54 > 0:00:56with bluebells, anemone and sorrel.
0:00:56 > 0:01:00- The idea of the food chain almost literally starts at our feet...- Yes.
0:01:00 > 0:01:03..with all this mulch and leaves around us too.
0:01:03 > 0:01:07You've got the remnants of all the autumn leaves that are still here.
0:01:07 > 0:01:10Some of the small branches. It's the woodland's own composting system.
0:01:10 > 0:01:15The leaves are decayed by the worms and the invertebrates here that break that down.
0:01:15 > 0:01:18By breaking it down, they're enriching the ground vegetation
0:01:18 > 0:01:23that provides the sustainability for new generations of oaks and woodland flowers to come up.
0:01:23 > 0:01:24There's an example of this here.
0:01:24 > 0:01:28It's this fallen piece of timber here, that is showing
0:01:28 > 0:01:29the development of fungi.
0:01:29 > 0:01:31And you have allowed this to stay here?
0:01:31 > 0:01:33Yes, as that's a habitat in itself
0:01:33 > 0:01:38for hibernating hedgehogs, woodlice, all our different invertebrates in the woodland.
0:01:38 > 0:01:41- There's moss on it. - There's moss here and fungi.
0:01:41 > 0:01:44But it's all part of the breaking down of the whole leaf,
0:01:44 > 0:01:47which is a very rich habitat in itself.
0:01:47 > 0:01:50The leaf litter and branches and fungi and moss
0:01:50 > 0:01:54are creating sustainability in the future for the rest of the woodland to continue.
0:01:54 > 0:01:59The oak trees that we're surrounded by have been here for hundreds of years.
0:01:59 > 0:02:04If we go further into the forest, we can actually see how fragile their existence has been.
0:02:04 > 0:02:06There's a good example of that upstream here.
0:02:06 > 0:02:08We can take a walk there now.
0:02:09 > 0:02:14Seamus, we're deep in the woods now and there's a real sense of...
0:02:14 > 0:02:17- It's almost like we've time travelled.- Yes.
0:02:17 > 0:02:19We're surrounded by the mighty oak.
0:02:19 > 0:02:23Is it true that a lot of these oaks could be from the 17th century?
0:02:23 > 0:02:27You're dating back here to remnants of an ancient woodland.
0:02:27 > 0:02:29The oaks have been here a long time.
0:02:29 > 0:02:30Some wouldn't be that old,
0:02:30 > 0:02:34but ground conditions here are associated with an ancient woodland.
0:02:34 > 0:02:38Looking up at the oak trees there, they seem to be perched on rock.
0:02:38 > 0:02:45Yep, yep. You wonder how they can be sustained in such a thin layer of the soil,
0:02:45 > 0:02:50but the oak trees have one major taproot and that's a very aggressive, vigorous, root system.
0:02:50 > 0:02:54It penetrates most of the rock to look for water and food source.
0:02:54 > 0:03:00Coupled with that, it's got a lateral root system, which is also supporting the tree on the top.
0:03:00 > 0:03:03It may look as if it could topple over, but it's quite strong and safe.
0:03:03 > 0:03:05The oak tree, then.
0:03:05 > 0:03:07How significant is it to the food chain
0:03:07 > 0:03:09that we've been talking about in the forest?
0:03:09 > 0:03:12The oak is probably the greatest tree
0:03:12 > 0:03:17as it supports over 400 species of wildlife, from moss and lichens to invertebrates, spiders, insects,
0:03:17 > 0:03:21which are part of an ecosystem supporting the woodland.
0:03:21 > 0:03:23When I come back, later into spring,
0:03:23 > 0:03:25what changes am I going to see?
0:03:25 > 0:03:27You'll wonder if you're in the same woodland,
0:03:27 > 0:03:30because the transformation will be immense.
0:03:30 > 0:03:33Each season brings everything into its own.
0:03:43 > 0:03:45There's one sitting on the ground.
0:03:45 > 0:03:49- Just below the...- Oh, there is one just sitting there, look.
0:03:51 > 0:03:53On top of the feeder, there's a red squirrel.
0:03:53 > 0:03:58I do believe that's the very first time I've seen a red squirrel in the wild.
0:03:58 > 0:04:01The success of the project is down to these feeder stations.
0:04:01 > 0:04:05The challenge was to get a feeder that fed the red squirrels,
0:04:05 > 0:04:09but didn't feed the grey squirrels, which totally excluded them.
0:04:09 > 0:04:12So what we came up with was basically a hole or a plate,
0:04:12 > 0:04:17getting the minimum size that red squirrels could get to, but grey squirrels couldn't.
0:04:17 > 0:04:20What's the size difference between a red and a grey squirrel?
0:04:20 > 0:04:24A red squirrel is 300g and a grey squirrel is approximately 600g.
0:04:24 > 0:04:26- Almost twice the size?! - Twice the size, yes.
0:04:26 > 0:04:29- So the hole is vital? - The hole is vital.
0:04:29 > 0:04:32He's got in through the hole, so what's going on there?
0:04:32 > 0:04:34The squirrel has to go through the hole,
0:04:34 > 0:04:36physically open the flap and take some food.
0:04:36 > 0:04:38There's a little platform in there.
0:04:38 > 0:04:41He can sit quite happily, as there's a hole either side.
0:04:41 > 0:04:44If a predator comes along, he can make a quick exit safely.
0:04:44 > 0:04:47- So they're inquisitive? - They are, yes.
0:04:47 > 0:04:49- Adventurous?- Yes.
0:04:49 > 0:04:52- And very nimble?- Yes, very nimble. I hear another one.
0:04:52 > 0:04:56- Do you hear another one? Where? - You can hear them running up and down the trees.
0:04:56 > 0:04:59- You can hear their nails on the bark.- Do they cling on to the bark?
0:04:59 > 0:05:02They do. They go up and down, sometimes in a spiral movement.
0:05:02 > 0:05:05He's gone! Look, he's out, he's out, he's away.
0:05:05 > 0:05:07There he goes, going up the tree.
0:05:07 > 0:05:10What they quite often do is they'll get a certain amount of food
0:05:10 > 0:05:11and then they'll cache it.
0:05:11 > 0:05:15- Hide it?- Yeah, they dig little holes and they put it in
0:05:15 > 0:05:18and use their wee paws and tramp it down.
0:05:18 > 0:05:20That's what he's doing at the moment.
0:05:20 > 0:05:22Why is the grey squirrel a threat?
0:05:22 > 0:05:27It's eating a lot of the food that the red squirrel would naturally eat.
0:05:27 > 0:05:29It also carries a disease called pox virus.
0:05:29 > 0:05:33The grey squirrel is immune to the pox virus,
0:05:33 > 0:05:36but if it comes in contact with the reds and passes it on,
0:05:36 > 0:05:38it kills the red squirrels within weeks.
0:05:38 > 0:05:40The two can't live hand-in-hand?
0:05:40 > 0:05:42I think it's unrealistic
0:05:42 > 0:05:45to think that you could get rid of all the grey squirrels,
0:05:45 > 0:05:46but I think in areas
0:05:46 > 0:05:49where there's a good, strong, red squirrel population,
0:05:49 > 0:05:53it's very important that a grey squirrel population is managed.
0:05:53 > 0:05:56- We're talking about culling here? - Yes.
0:05:56 > 0:05:57And basically,
0:05:57 > 0:06:00if you want to keep reds, you have to keep grey numbers down.
0:06:02 > 0:06:04There he goes, he's had enough, has he?
0:06:04 > 0:06:09How many red squirrels are there today, and how many were there when you started up in your group?
0:06:09 > 0:06:15- 11 to over 100 in four years. - That's not bad.- Yeah.
0:06:15 > 0:06:20Nowadays, you have more chance of seeing red squirrels in Tollymore than you do of greys.
0:06:20 > 0:06:22I think we'll sneak away now, will we?
0:06:22 > 0:06:26Let these guys enjoy themselves. Thank you for allowing me to be part of today.
0:06:26 > 0:06:28It's a day I'll never forget, actually.
0:06:35 > 0:06:39Seamus, I was here with you about two months ago.
0:06:39 > 0:06:43- There's such a difference today.- Yes. - Firstly the smell, birdsong too.
0:06:43 > 0:06:47And an absolute galaxy of colour here.
0:06:47 > 0:06:50The bluebells, and what else have we got?
0:06:50 > 0:06:52There's this beautiful stitchwort flower.
0:06:52 > 0:06:56Beautiful little plant, yellow centre on it, little lobed petals on it.
0:06:56 > 0:07:02You've got the bluebell here with its six lobed flowers down one side. That's the native bluebell.
0:07:02 > 0:07:04OK, so this one is the real McCoy.
0:07:04 > 0:07:06This is the native one.
0:07:06 > 0:07:10And this means that this all around us here is a native woodland.
0:07:10 > 0:07:11Correct.
0:07:11 > 0:07:15Here you have ground conditions associated with ancient woodlands.
0:07:15 > 0:07:19Indicators like bluebells, stitchwort, wood sorrel and anemones are prominent here
0:07:19 > 0:07:22because of the association with ancient woodland.
0:07:22 > 0:07:25What I notice as well that has changed since I was last here
0:07:25 > 0:07:27is the canopy over us.
0:07:27 > 0:07:29You did talk about that the last time.
0:07:29 > 0:07:32- Can we go deeper into the forest? - We can. Follow through.
0:07:39 > 0:07:42The tree canopy's closing over, so the bluebells,
0:07:42 > 0:07:45the celandine and stitchwort have all tried to get up,
0:07:45 > 0:07:48before the last leaf has closed over, to get that last glimpse of light.
0:07:48 > 0:07:52So the little shafts coming through, that's what's keeping them going.
0:07:52 > 0:07:55They're all fighting for that glimpse of light,
0:07:55 > 0:07:58whether it's ground flora, wild flowers or sapling trees.
0:07:58 > 0:08:01They're all trying to get up through to survive.
0:08:01 > 0:08:03It's survival of the fittest.
0:08:03 > 0:08:04What's this yellow flower?
0:08:04 > 0:08:06It's a lesser celandine flower,
0:08:06 > 0:08:08another flower associated with ancient woodland.
0:08:08 > 0:08:12- Flowers here are actually fighting for survival.- Yes.
0:08:12 > 0:08:17Further along, there are saplings which possibly pose a threat to this natural woodland.
0:08:17 > 0:08:20- Can we have a look at them? - You can indeed, follow me.
0:08:29 > 0:08:32I see trees growing up all around me.
0:08:32 > 0:08:36I don't see any threat to the natural woodland. What's going on?
0:08:36 > 0:08:41There's a lot of mature beeches here, and unfortunately with their dense canopy,
0:08:41 > 0:08:46they're prohibiting the trees like the ash regenerating in here naturally.
0:08:46 > 0:08:49An example would be this small beech sapling here.
0:08:49 > 0:08:52- So that will grow into that? - It will. Very fast growing.
0:08:52 > 0:08:57The problem will be that once it gets up to that state there, with the dense canopy of the beech,
0:08:57 > 0:08:59it prohibits natural oak and ash.
0:08:59 > 0:09:03- Would you just pluck that out then? - You would pluck it rather than chop down a mature beech.
0:09:03 > 0:09:08They do have a wildlife value, but not like the oak and the ash in the woodland.
0:09:08 > 0:09:12Historically the beech are a pretty competitive tree. They'll grow quicker than the oak.
0:09:12 > 0:09:17It's funny, on either side of us there are shafts of sunlight coming down.
0:09:17 > 0:09:20- And there are bluebells growing there.- There are.
0:09:20 > 0:09:21Where we are now is quite barren.
0:09:21 > 0:09:25It's barren because the tree canopy above is quite dense with a lot of shade.
0:09:25 > 0:09:29It's going to take a very resilient plant to grow in here.
0:09:29 > 0:09:32Do you think that you're winning the battle
0:09:32 > 0:09:35and preserving the long-term future of these natural woodlands?
0:09:35 > 0:09:36Hopefully we are.
0:09:36 > 0:09:39It's a long-term programme, it's not overnight,
0:09:39 > 0:09:43but I do think we are winning the battle slowly but surely.
0:09:46 > 0:09:49Subtitles by Red Bee Media Ltd
0:09:49 > 0:09:52E-mail subtitling@bbc.co.uk