Tuesday 12 July 2011

Little blue lines on maps

June started with a bit of a shock. Ex-work colleague Bob had asked me for any lichen records I might have from the ancient aspens on his farm at Easter Tulloch to help with a grant application. Knowing how important these ancient aspen stands are for lichens and other flora and fauna, I offered to write a wee note about this to accompany his application particularly as the grant might pay for fencing to exclude stock grazing and allow trees to regenerate, or for planting new areas. Added to the note I provided a list of lichens “likely” to be present on Bob’s aspens drawing on information on common species that had been recorded by experts in the adjacent aspen woods and from other woods close by. Having recorded the lichen Lobaria pulmonaria on one of Bob’s trees (left), the only location for this species within the Tulloch aspen woods, I also suggested that a full survey by expert lichenologists might reveal other unusual species. Job done, Bob sent in his application, and I thought that would be that. I received an email the following day from the grant aiding body saying that I had been nominated as “lichen expert” for Bob’s farm, something I had to decline by return email explaining that apart from looking for and recording a few rarer lichens, I knew little about all the common species hanging thickly from Bob’s trees! Phew, me a lichen expert, they must have got me mixed up with someone else! I did offer though to help with butterfly recording, if needed.

We had another shock at the start of the month, the temperature, for two whole days, rose to the dizzy heights of 29 degrees C. Just what was needed now that all the Osmia bee nest boxes were installed and waiting for occupants. A walk along one of the Abernethy tracks where there were boxes and where the bee had been recorded in the past, found them visiting bird’s-foot trefoil flowers (right) at three different locations. A great start. A visit to a small lay-by at School Wood in the village (threatened with houses as endorsed by the Cairngorms National Park and housing association) with an abundance of trefoil flowers also found the bee on the wing, the first time it had been seen here since 2001. But that was it, and the following day temperatures dropped by 20 degrees, heralding what was to follow for most of the rest of the month. We even had several night-time frosts down to -2 degrees C! Janet’s flowers in the garden suffered quite badly and a check of a local site for one-flowered wintergreen showed several of the earlier emerging flowers had been browned off. The visit to the wintergreens was also to carryout a bit of habitat management, cutting back some of the ever expanding bushes of rhododendron particularly where the best flowering patch for the plant was being threatened. Getting rid of this ultra-invasive plant really is soul destroying, almost every branch that has grown outwards and is touching the ground, roots, converting a single bush into something quite monstrous, and if you don’t pull every bit up, off it goes again. In the west of Scotland trying to remove this plant is costing millions of pounds, and as you drive around the east of Scotland you can see a time-bomb gathering pace to explode. One of the plants on my most hated list. Searching around the site it was nice to find a single plant, sheltered from grazing sheep by a fallen pine branch, in a location where Janet and myself found it growing about 25 years ago. In another location a group of wintergreens were growing in a flowering patch of twinflower (left), something I’ve not seen anywhere else.

One of the plants on the list of the Cairngorms Rare Plants Project is small cow-wheat (Melampyrum sylvaticum). Andy Scobie is the Project Officer and had mentioned this plant to me whilst helping out with lesser butterfly orchid counts in the area. There are a few extant sites for the plant in the Cairngorms National Park but many more “old” records where it hasn’t been seen for a long time. Many of the old records also have little accurate data regarding exact location so it’s quite difficult to know where to start looking. One of the best ways of knowing where to look is to try and see the plant at one of the known sites and hence we come to the first of “the little blue lines on a map”. The small cow-wheat at some sites seems to like to grow in or close to damp woodland. It is a parasite and has to have its host plant blaeberry/bilberry close at hand. In 2004 it had been recorded from a site close to Inverness “on a grassy area under hazel and birch above and 3 metres from a wee burn with blaeberry and the grass Holcus mollis and bracken”. Little did I know just how valuable that tiny bit of information would be. There was a grid reference but only to an accuracy of 100 metres. The easy bit was finding the little blue line on the map, a small burn running south from the River Nairn. Thankfully I had put my wellies on and was able to walk in or along the burn checking for suitable sites. The first interesting find was sanicle growing at the base of an incised outcrop of conglomerate (a concrete like rock consisting of pebbles and gravel embedded in what looks like cement). The moist site had lots of ferns including the tiny brittle bladder fern. Initially the banks were too steep to match the description and, there was no blaeberry! The first hour of searching failed to find anything and considering I was trying to find a patch of plants one to two metres square, I was beginning to think of failure. A little further up the burn the bank became less steep and the mix of hazel and birch was still present and I decided to concentrate on looking for blaeberry and Holcus mollis rather than the wetter areas I had been searching. A larch tree gave a bit of hope and the first plants of blaeberry but a check of my GPS showed I was now in the wrong 100m OS grid square to the one from the last record. Sparse bracken and some blaeberry under hazels indicated I might be in the right area so I kept looking and it was with great relief that as I climbed up the bank from the burn a cow-wheat plant with tiny flowers came into view (above right). Small egg-yolk yellow flowers a few with a touch of orange and the flowers no longer than the green calyx from which they grew told me that this was the plant I was looking for (compare with common cow-wheat left). Time for a sandwich (just as the heavens opened) and a count of the number of plants, a quick photo before heading for home now knowing what I was looking for elsewhere. This one was easy, now to try and find the plant at Kinrara near Aviemore where the last grid reference from 1890 gives the location to the nearest one-kilometre grid square!

It’s been a bit of a month for trying to re-locate old plant sites. The location of herb paris in the Pass of Ryvoan woodlands has been a bit of a challenge for a few people over the last few years and despite the late Mary McCallum-Webster recording the flower from two locations neither have been found in recent years. I made the pilgrimage mid-month and joined the list of failures but then every cloud has a silver lining and the visit resulted in finding yet another group of ancient willows with the three Lobarian lichens (L. pulmonaria, scrobiculata and amplissima), masses of woodruff and a rare sedge locally wood sedge (Carex sylvatica right). Climbing high into the scree zone gave a great view of the Green Loch – Lochan Uaine. A visit to the same loch a day later was a slightly sadder affair but at the same time a celebration of the life of a neighbour in Nethybridge who had walked and cycled the tracks of Abernethy and Glenmore and who wanted her ashes to be scattered by the loch. She chose a good spot and those present enjoyed the view from the loch to Ryvoan Bothy as they said farewell. The couple of visits to Kinrara have also failed to re-find the small cow-wheat but an erupting willow warbler from my feet revealed a nest full of chicks, the biggest population locally for a rare grass mountain melic (Melica nutans) and false-broom (Brachypodium sylvaticum), oak and beech ferns growing together and masses and masses of common cow-wheat – some with small flowers. The search goes on.

The next “little blue line on the map” to be visited was near Ballindalloch Castle, and was a follow up visit to one made by ex-work colleague Andy where additional woodland needed to be checked for coral-root orchid. During his visit he had found huge numbers of the orchid in a mixture of wet willow/birch woodland where an earlier record had stated that a few plants had been found. I had been visiting this area of the last couple of years looking for this plant but had been looking in the wrong bit of woodland! Dooh! So, the start of the little blue line was located - the small burn that would eventually lead to the area to be checked. I had hardly left the road when the first orchids were found and this was nowhere near where I was supposed to be searching. A good omen. As I worked my way up the burn more small groups of orchids were found and as I approached the area where Andy had concluded his search, larger numbers were found. This orchid is quite beautiful in its own way. It lacks the bright colours, showy flowers and leaves of other orchids and even when the pale yellow flowers are “fresh” they look like they have just gone over (right). The flower doesn’t photosynthesise like most other orchids/flowers having almost no chlorophyll in its make up but relies on the fungi that live in the coral-like lump at the base of its stem for most of its nutrients. Bird’s nest and ghost orchids grow in a similar symbiotic way. The coral-root orchid is also self-pollinating and has no nectar or scent to attract insects. Amazing. I digress. The little blue line eventually gave way to a series of areas of boggy willow woodland and it was within these areas that the majority of orchids were found and our combined total of 400 flowering spikes is probably the largest population known locally, and a bit of additional woodland that I thought have been counted, wasn’t even visited. Beech fern and pale sedge were also new to the site and a group of bird cherrys in the drier woodland were totally covered in spooky webs (left) of the munching army of ermine moth caterpillars (visit http://ukmoths.org.uk/show.php?bf=424 to see it).

An email mid-month lead to me renewing my links to the pinewood hoverfly (Blera fallax) project. PhD research student Ellie had been rearing and releasing adult hoverflies at a location in Abernethy Forest where the fly had been last seen in the 1980s and where larvae had been released in artificial rot-holes the previous autumn (see November 2010 diary). Ellie was having to head south to get on with writing up her thesis and a few adults had yet to emerge before being released and would I like to be foster-dad to any that might emerge? What an opportunity to be involved with this bonny wee fly at the most important part of its life just before it heads off into the wilds of the forest to search for a mate and ensure the next (and first new wild) generation of pine hoverflies continue as part of the forest ecosystem. It took a few days for the first hoverfly to emerge and I found it hanging upside down on white gauze covering the top of the “pot” – actually a white plastic catering cup. Most of the flies emerge first thing in the morning and spend the next few hours “pumping up their body and more importantly, their wings, in preparation for their first flight, best described as the fly swaying gently back and forth whilst trying to pump itself up a bit like a very constipated human on the loo! Then came the tricky bit. Ellie likes to have a record of the biometrics (size of head, body, wings etc) of each fly that emerges and this is achieved by placing the fly on a squared piece of encapsulated paper to have its photo taken (left). The squares on the paper are 5mm in size and from that the fly’s measurements can be deduced. With luck the fly might stay still when on the grid but more often than not they run around or climb up into the wee plastic pot kept close to hand in case the wee beastie tries to take off, so great patience is needed whist waiting for the right moment to release the shutter. Photo taken they are left quiet for an hour or so before being taken to the release site in the forest (right), the first three having to wait for gaps in some fairly wet weather. In all, five hoverflies were released and from the body markings it was noted that 4 were female and 1 was male. We wish them all well and I hope I have played a little part in helping the pine hoverfly to re-establish itself in the forest close to Loch Garten. See
http://www.mallochsociety.org.uk/blera-2006-status/ for more information.

The month ended with a bit of paid work – recording patches of bird’s-foot trefoil along several tracks in Abernethy, a repeat of a survey carried out ten years ago. Locations of patches were recorded along with size and quality/quantity of flowers. Bird’s foot trefoil flowers support a wide range of insects including the wee bee Osmia uncinata which was mentioned in the last diary. As the major management projects have declined (mainly timber felling and extraction) the track verges have received little disturbance and without disturbance, the populations of the plant will decline. The survey found that whilst the plant was found in many of its 2001 haunts, very few of the patches were producing many flowers, and if the track verges are not disturbed a little, the plant is likely to disappear under masses of heather and young pine trees. Watch this space.

It was also the time of year for counting lesser butterfly orchids at two local sites. The field in Tulloch produced just 6 flowering spikes this year and at the other site by the B970 it was obvious that there would be less flowers than the massive count of 2800 in 2010. Once again late frosts had caused many flowers at the main site to keel over (left), along with some of the fragrant orchids, though these would be included in the count. One of the mysteries to be solved in the lesser butterfly orchid world is what insect or insects are responsible for pollinating the flower and to try and answer this question a couple of local moth experts had offered to help the Park’s rare plants officer by running a few moth traps at the site to see if any of the moths trapped had the right “pollinia” attached to their head, eyes or proboscises. To ensure pollination the orchids have developed some pretty novel methods when compared to other flowers which have “free flying” pollen, where the pollen can cross-fertilise nearby flower by wind-borne pollen grains or by the grains being transferred from flower to flower by insects. In orchids all pollination is by insects and to ensure this is carried out successfully the orchids provide the pollinators with a landing pad, the bottom lip of the flower, and “landing lights” ultraviolet guides (invisible to humans) which guide the pollinator towards the orchid’s pollen masses or pollinia. The pollinia (above right photo © Mike Taylor shows 3 types of pollinia) are stored in the flower behind the anther cap (male sexual part of the flower) and as the insects explore the flower the clubbed shaped pollinia (pollen mass) with a sticky pad at its base, glue themselves to the part of the pollinator that comes into contact with them. The insect’s role is then to carry the pollinia to the stigma (female part) of other orchids to ensure fertilisation. The tricky bit would be trying to identify whether the right pollinia was attached to any of the moths trapped, not easy when the trap site had three species of orchids present. Would they even be any pollinia? The moth traps did their job and indeed there were moths with pollinia (The Spectacle moth left) but so far all have been identified as coming from the fragrant orchids. After the traps had been emptied I stayed on at the orchid site to see if I could physically see anything visiting the lesser butterfly orchids. The first “insect” to appear that was interested in any of the orchids was a six-spot burnet moth, but all it (and others later) was interested in was the fragrant orchids and at one flower spike I watched the build-up of pollinia on the moth proboscis (right) as it probed into each flower on the spike. One of the moths from the trap had 20 pollinia attached to its curled up proboscis! The next day was count day but sadly an on-going injury to one of my thigh muscles meant I had to pull out of the count. The count though was completed and this year’s total was 800 lesser butterfly orchids. The summer is flying by far too quickly.

That’s it, enjoy the read.

Stewart & Janet






Brother Peter at the end of his Coast to Coast charity ride
Budding Tarzan - grandson Archie
New bird for Firwood garden - scarlet rosefinch




All photos © Stewart Taylor