Research on orchids

I have been occupied for the past 6 months with research on people in Britain making wine and beer at home using wild plants. While I had less time outdoors looking at native orchids this year I learnt a lot about the way people identify and select wild plants for use. I am now starting to work on a PhD 'Salep: Turkey's wild orchid harvest'.

With Central Middle Eastern as well as European flora both found in Turkey there are three times as many orchid species growing in Turkey as there are in Britain. Some of the species I will be looking at are quite different to those found in Britain but many of the species found in Britain also grow in Turkey.

One of the advantages of the limited flora in the relatively small geographical area that constitutes Britain is that there are often detailed records on particular species. Data on British orchid populations will be useful in analysing the data I will be collecting over in Turkey.  So while I am getting to grips with Turkish orchids I will also be learning a lot more about the orchids growing in Britain.

Coastal Orchids

The seaside might not be the first place you think about as a place to see orchids but it is a great location for a variety of orchids including several of the less common species. I’m inspired to think about coast orchids at the moment as Roddy Jenkins is walking the South West coast path to raise money for the National Eczema Society http://www.justgiving.com/Roddy-Jenkins On his journey from Minehead in Somerset to Poole in Dorset over the next few weeks the path will take him past Early-purple and Green-winged orchids in bloom. He might spot the rogue colony of Serapias that are reputed to be found on the Devon/Cornwall border.

Thinking about orchids in Britain they tend to be associated with thoughts of cool lush meadows and woodlands. However many tuberous orchids are well suited to coastal conditions where fresh water can be limited and winds are strong. The tubers of some orchids including Early-purple, Green-winged and Lizard orchids contain glucomannan – a molecule that retains water and lowers freezing point. These two properties provide drought tolerance and frost resistance to plants .With the bulk of leaves in basal rosettes the drying effects of wind are also reduced.

Coastal locations offer a range of different habitats. Dune slacks, the hollows between dunes, can provide damp or marshy conditions where groundwater level is above the soil level. Dune slacks are a great location for Marsh helleborines. Steep slopes where the soil is a thin layer over chalk and the land is grazed are where I have found Autumn Lady’s-tresses. Dune helleborines, as indicated in the name are found in sandy soils. One rainy day in Lancashire I spotted their distinctive sickly green leaves under pine trees on the Lancashire coast. It was too rainy to get a photo of the opening flowers but living in the south I was delighted to see a plant that has a northerly distribution. On the north coast of Scotland I found Twayblades running through the sand dunes flowering in August; when the first Twayblade I had seen that year was open in May in the south.

So while there is plenty to keep me busy on or in the water getting down to the shore it is always worth looking out for the plants that grow on the coastal cliffs and sand dunes.

Timing

Thinking ahead about seeing different orchids in flower this year I am considering what I would like to see and good places to see them. Finding about where to go to see them is a matter of linking up with your local wildlife trust, natural history group or referring to books or forums.  You can of course go for walks in likely places, enjoy the surroundings and if you see an orchid that is a bonus. The critical factor is arriving at the right time which as well as being species specific is influenced by the weather.

Two weeks late has been suggested as the delay in flowering this year by some conservation organisations. There was a cold snap earlier this winter but down in Dorset it has been mild since then and melon seeds are sprouting on my compost heap.  The delay of two weeks may be accurate for the country as a whole or skewed by the heavy snow that the north of the country had for significant periods of time.

Temperature has a role to play in onset of flowering. Having spent the winter between Dorset and Kent my current feeling is that in east Dorset flowering times will be pretty much in line with the books (unless there is a prolonged cold snap between now and April). West Dorset may have been a little colder but not enough to delay flowering by more than a week. Kent seemed to have colder weather so I think that this year the glorious east Kent orchids will be about a week to ten days late.

Just as aspect influences the growth of plants in a garden it also influences the growth of wild plants. Exposed locations, north facing slopes and frost pockets will delay flowering in comparison to nearby sites or different parts of the same site that have more favourable conditions.

Phenology is not just about temperature. For orchids winter rainfall also determines onset of flowering. During winter months low levels of rainfall inhibit development of roots and tubers. As these fuel growth of flowering spikes limited winter rain can delay flowering while the plants build up reserves using water later in the year.

Regional variations also play a role. The Early Spider-orchids in Dorset are always out several weeks before those in Kent. Further north flowering times are delayed. Burnt Orchids (Neotinea ustulata) have two different subspecies  (N. ustulata subsp ustulata and N. ustulata subsp aestivalis.  So depending on which variety Burnt Orchid colonies  are composed of different timing will be required to see them.

Last year I found a few White Helleborines (Cephalanthera damasonium) in bud. According to the books they should have been in their prime of flowering, but spring and early summer were running two weeks late. I returned two weeks later to find the same plants in full flower. Additionally because plants were flowering a site which had seemed to have just a few plants was clearly full of them as they are so much easier to spot in flower.