Misty mornings in the Araucaria forest

This blog follows on directly from my previous blog, ‘The Araucaria forests of Chile, part 2‘, which ended up with me descending from the Sierra Nevada ridge in Conguillio National Park at night, with low-lying clouds covering Lago Conguillio and the surrounding forest. I knew then that the next morning the Araucaria forest would be shrouded in fog, which is one of my favourite times to be out in it. So although I was very late getting back to my campsite, where I then had to cook my dinner before going to sleep, I planned to get up early the next morning to take advantage of the special weather conditions.

After what was a short night, I was back out in the forest again just after 7 am, in time for the first light of the new day. In fact, it dawned rather dark and grey, because the fog was very thick, as I had suspected, and it transformed the atmosphere within the forest. For me it enhanced the primeval quality of the Araucaria trees (Araucaria araucana), whose lineage on the planet harkens back to the era when dinosaurs were the predominant animals on the land.

The trees were dark silhouettes amongst the all-enveloping fog, with their colours only becoming apparent when I was very close to them. This was particularly true for the ñire trees (Nothofagus antarctica), a short deciduous species whose leaves were already rich shades of red and orange, although being in mid-April it was supposedly only the beginning of the autumn season. The moisture from the water vapour that formed the fog also nourished the old man’s beard lichens (Protousnea spp.) that festoon the trees of both species, helping them to swell up to their fully-hydrated size and increasing their prominence in the forest.

After a little while, as the sun (which I couldn’t see of course) began to warm up the air, the fog began to drift around a bit. Sometimes it was quite dense, while at other times it was much thinner, and the colours of the vegetation became quite apparent in the much brighter conditions of light. I could almost feel the forest breathing, with the trees and lichens absorbing moisture from the fog, and the lichens especially seemed to be at their most exuberant fullness of life, radiating vitality through their vibrant colours.

There are several species of old man’s beard lichens (Protousnea spp.) that occur in the Araucaria forest, and they often form dense curtains of pale yellowish-green threads hanging from the branches and trunks of the trees. As is typical for arboreal lichens, they gain their moisture from rain or fog and all their nutrients from particles of dust and organic matter that drifts in the air. Their abundance here in the Araucaria forest is an indication of how clean the air is. Arboreal lichens disappear in the presence of atmospheric pollution, because they absorb the pollutants as though they were food particles and, in effect, die from poisoning.

While the old man’s beard lichens are generally uniform in their appearance, some of their pale strands have brown disc-like shapes on them. These are the apothecia – the reproductive structures of the fungal partner in the lichen symbiosis. They release the spores of the fungus, which are microscopic in size and can travel long distances on the wind. Once the spores settle somewhere they have to encounter some of the algal partner in the symbiosis for a new lichen to get established.  The main method of reproduction for these lichens is much simpler though. Hanging strands of the ‘beards’ will get broken off in storms etc and some of them are carried by the wind to the branches of other trees, and if they get caught there, will grow on to become new lichen populations.

 

 

 

 

 

 

 

The ñire trees seem to have a natural variation in the colour that their leaves change to before being shed in the autumn. While many of them go an orange-brown colour, others turn deep shades of red. I don’t know whether this is due to a natural variation in the trees’ internal chemistry, or a result of slightly different soil conditions that give rise to the range of different colours when the trees withdraw their chlorophyll, prior to dropping their leaves for the winter.

The light levels in the forest continued to fluctuate considerably as the fog drifted by, with denser patches alternating with brighter periods when the mist thinned out. Then, through the fog came the distinctive squawks of one of the characteristic birds of the forest – the austral parakeet or cachaña (Enicognathus ferrugineus). It’s the most southerly-occurring parrot in the world, with a range that stretches from the southern tip of South America to the northern end of the Araucaria forests in Chile. In the autumn, the parakeets gather together in noisy flocks, flying over the forest in search of female Araucaria trees with ripe cones on them. They act as the main dispersal agents for the seeds, or piñones, of the trees, breaking open the large cones, which can be up to 20 cm. in diameter, 4.5 kg. in weight and contain as many as 200 seeds. Some video footage of the parakeets feeding on Araucaria seeds is in one of my previous blogs here.

A small group of parakeets landed in the upper branches of an Araucaria tree near where I was standing, with their silhouetted outlines standing out against the murkiness of the fog. Their colours match those of the Araucaria foliage very well, but it was hard to tell that in these dull conditions. The Araucaria trees are a mast fruiting species, meaning that in some years they produce a large quantity of seeds then for several of the following years they don’t produce much at all. This was one of those latter years, with not many cones available, whereas when I’d been in the same forest two years previously it had been a spectacularly abundant year for piñones.

The parakeets didn’t stay for long, as there didn’t seem to be any cones on the trees where I was, so they flew off, presumably to  search in other parts of the forest. I continued to explore the area, which is not far from the base of Llaima Volcano. That’s one of the most active volcanoes in Chile, and it erupts regularly – the most recent occasion was in April 2009. In many places in the park the forest floor is bare, as vegetation hasn’t yet fully colonised the ash and cinder surface left from previous eruptions. These conditions are ideally suited for the ñire tree, as it prefers sites with dry soils, such as volcanic ashes, which is why it is so prolific in this part of the forest where I was.

Elsewhere in Conguillio National Park, especially on the mountain slopes and areas with more fertile soils, other species of Nothofagus predominate, particularly lenga (Nothofagus pumilio) and coigüe (Nothofagus dombeyi). The Araucaria tree is well-adapted to the volcanic conditions of its habitat, and there were plenty of young seedlings visible, growing amongst the ash and cinders on the forest floor.

I stopped to have a closer look at one particular seedling, as it seemed vibrantly green with life in contrast to the dark cinders all around. My eye was drawn to some delicate strings of water droplets stretched out on lines of silk connecting the tips of some of the seedling’s leaves. These were part of a spider’s web, and they would normally be invisible to the casual human observer. However, on this day the fine tracery of silken strands was highlighted by the dew drops that had condensed from the fog.

The beauty of this miniature scene touched me deeply, and I spent a little while enjoying and appreciating it from different angles, taking photographs as I did so. It was another one of those ephemeral phenomena in Nature that you have to be in the right place at the right time in order to see and experience. As the day warmed up, the moisture would evaporate in another hour or two, and the silken strands would become invisible again. That would make the spider happy I’m sure, as I guess that, unlike me, it doesn’t appreciate these misty mornings, because they reveal the location of its web, thereby enabling insect prey to avoid it!

As I walked around, my attention continued to be drawn to various details within the forest. There were a number of large old Araucaria trees in the area, so I had a closer look at them, knowing that there are some special lichens that grow on their trunks. On one tree in particular I found some good patches of one of those – the blood spot lichen (Ophioparma araucariae). As its specific name indicates, this species only occurs on the trunks of Araucaria trees, although a similar-looking close relative (Ophioparma ventosa) occurs on rocks in the Caledonian Forest in Scotland. The common name is the same for both species, and is derived from the blood red colour of the apothecia – the red disc-like shapes visible in this photograph. On this tree it was growing beside another of the old man’s beard lichen species – in this case Protousnea teretiuscula. I’m very grateful to Reinaldo Vargas, a lichenologist based in Santiago in Chile, for his generous help in identifying this and many other lichens that I photographed during my trips to the Araucaria forests.

On the trunk of another old large Araucaria tree I made an even better discovery. Once again, my eye was drawn to the bright red apothecia of the blood spot lichen (Ophioparma araucariae), and this time it was surrounded by a diverse group of other different lichens, shown in this photograph here. Thanks to the expert help of Reinaldo, I was able to get all of them identified, and they are as follows: upper left (bright pale green) – Pseudocyphellaria citrina; upper left (dark green and just below the previous one) – Nephroma antarcticum; old man’s beard lichen (in the lower centre) – Protousnea poeppigii; lower half of the photo (dull green, surrounding the old man’s beard lichen) – Pseudocyphellaria granulata;  and in the centre of the image on the right hand edge (dark green and thread-like) – Bryoria araucana.

This latter one was particularly exciting to find as it is another lichen that is specific to Araucaria trees (as its scientific name implies), and it was only recently discovered and described scientifically by lichenologists in 2015, from the trunks of Araucaria trees in Conguillio National Park. For anyone who is taxonomically minded, the paper describing it as a new species can be read here. I’m guessing that it has seldom been photographed, and these images here are almost certainly unique in depicting two of the lichen species that only occur on Araucaria trunks, growing together like this.

Not far away, my attention was drawn to the trunk of another large, old Araucaria tree for a different reason. It was free of lichens, so the polygonal plates of its bark were clearly visible and some of them bore distinct evidence of a fire. This took the form of blackened char marks on some of the raised ridges on the bark plates, and it looked like they had been burnt a few years previously. Because fires are a regular occurrence due to the volcanic activity in the area, the Araucaria trees are adapted to fire, and they have bark that is up to 15 cm. thick, which protects the cambium tissues underneath it.

This particular tree looked to be in good health, and judging from its size it must have been several hundred years old – Araucaria trees can live for over a thousand years. The fire appeared to have charred only the outermost parts of its bark, perhaps because it had been a low intensity burn, due to the relatively open structure of the forest here.

 

 

 

 

 

 

One of the notable features of the ñire trees in this area is the relatively high number of them that are hosts to a type of mistletoe known locally as injerto (Misodendrum punctulatum). This grows as a small, multi-branched yellowish-green bush on the stems and branches of the ñires and other Nothofagus trees in the forest. It is a hemiparasitic species, meaning that it derives some of its nutrients from the host tree on which it is growing, but also gains some nourishment from the sun through the presence of the chlorophyll which gives it its distinctive colour.

Because of the low height of the ñire trees here, it is possible to see some of these hemiparasitic plants in detail at eye level; on the other, taller Nothofagus trees, they are usually on the upper branches, perhaps 10 or 20 metres above the ground. I spent some time studying one of the injerto plants on a young ñire tree – as it was just about a metre off the ground it was easy to look closely at it and take some photographs.

One of the features of this species is that its leaves have been reduced to scales on its branches, presumably as an adaptation because of the plant’s reduced need for photosynthesis. There are in fact several different species of hemiparasitic mistletoes in the genus Misodendrum that grow on the Nothofagus trees in Chile, but this one is the most common. A large tree, such as lenga (Nothofagus pumilio), can host dozens of them when it is mature.

The mistletoe produces small flowers in the spring, and by the late summer and early autumn these have developed into seeds that have bristly threads attached to them. At the time of my visit, most of the seeds had already gone from the plants, but as I walked around, I came across some mistletoes that still had clusters of seeds attached to their branches. Dispersal is by the wind, and if the seeds become attached by their bristles to another tree, they will begin growing there.

This wind-aided method of spread is the same as that utilised by the old man’s beard lichens (Protousnea spp.). However, in that case it is fragments of an existing lichen that are blown from one tree to another, whereas with the mistletoe it is the specially-evolved seeds with their sticky bristles that perform the same function. Having found some seeds of the injertos, I then began to search a few young ñire trees nearby, and after a few minutes I found one that had some seeds freshly attached to one of its branches.

These will germinate next spring and there is then a period of up to four years when the new mistletoe develops within its host, using the tree’s resources, before it produces any aerial growth of its own. Individual mistletoes can live for up to 25 years and reach a size of up to 30 cm. across.

 

 

 

 

 

 

Although it sometimes thinned out, the fog was persisting for quite a long time this day, and certainly more than the hour or so that I had expected. Just when I thought it was going to be burnt off by the sun it would suddenly become denser again. This provided me with an extended time for photography in these special conditions, and I revelled in what seemed to me to be a real gift of the elements. Then, as I continued to walk around, I noticed some motion amongst the trees, at the periphery of my vision.

Turning to see what had caught my eye, I spotted a Magellanic woodpecker (Campephilus magellanicus) on the trunk of a ñire tree. Its bright red head indicated that it was a male, and it must have been the motion of it landing on the trunk that had drawn my attention. This is the largest woodpecker in South America, and one of the largest in the world, with a body length of up to 45 cm. It’s one of the most conspicuous birds in the Araucaria forest, and feeds mainly on grubs and beetle larvae that live within the trunks of the Nothofagus trees.

Using some small ñire trees as cover, I crept a little closer to get a better view of the woodpecker, unobscured by any intervening foliage. It seemed unconcerned by my presence as it worked its way up the tree, tapping at the trunk.

 

 

 

 

 

 

Then, as I watched, it was joined by a female bird, which I assumed was the male’s mate. Going around the trunk in what seemed like a coordinated fashion, they ascended together as they searched for larvae and grubs. My enjoyment of the action was interrupted though when some more movement off to my left caught my eye. I turned my head just in time to see a smaller bird, which I didn’t immediately recognise, land on the branch of an Araucaria tree. Looking at it through my telephoto lens, I thought it might be another woodpecker, and this was confirmed when I consulted a Chilean ornithologist, who identified it as the Chilean flicker or pitío (Colaptes pitius). It didn’t stay on the tree for very long though before it flew off again, so I only managed to get a couple of photographs while it was there.

Turning my attention back to the Magellanic woodpeckers, I was surprised (and delighted) to see that a third bird – another female – had joined the other two. It was obviously a family group, with one of the females being a juvenile from the breeding that had taken place in the spring, a few months earlier. I couldn’t tell which of the two females was the adult bird, but it is typical behaviour with this species for a young bird to stay with its parents for two or three years before becoming fully independent.

I watched the woodpeckers for a few more minutes, appreciating the wonderful gift of their presence on this foggy morning. Then suddenly, one by one, they flew off, first one of the females, then the other and finally the male. By the time the male went, I was ready with my camera and just managed to get one photograph as he flew away through the trees.

 

 

 

 

 

 

I had the feeling almost that they had spent so long in this area just for me, so that I could experience them as part of the forest and observe their behaviour as a family. It was a highlight of another very special day for me in the Araucaria forest.

The sun never did come out that day, as the fog just rose up and turned into clouds that filled the sky completely. That was a slight disappointment, as I’d been hoping to get some dramatic images of Llaima Volcano being revealed as the fog cleared. The next morning, which was to be my last in Conguillio (and indeed in any of the Araucaria forest areas) for this particular trip to Chile, was also foggy, but this time it seemed thinner and more like mist.

I was out early in the forest again, and noticed that although it was foggy, the atmospheric conditions seemed palpably different from those of the previous day. Sure enough, after an hour or so, the fog began to thin out rapidly. Blue sky appeared overhead and the mist dissipated to reveal Llaima Volcano, just as I’d hoped for.

 

 

 

 

 

Once it started to dissipate, it took a remarkably short period of time – 10 or 15 minutes at most – for the mist and fog to vanish completely. The sky became completely cloudless, providing excellent views of the snow-covered cone of Llaima Volcano, which is the centrepiece of the park. I had a couple of hours still before I had to leave and drive to the airport a couple of hours away, to begin my journey back home to Scotland, so I savoured that time fully, enjoying the Araucaria forest in the sunshine. When I left though, I couldn’t help but feel a deep twinge of sadness that I would miss the misty mornings that would follow, as they seem quite typical for this remarkable forest in the autumn.

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