Monday 13 June 2011

Heath

This heathy area was under coniferous plantation until about 8 years ago, and the original flora and fauna are now slowly returning as the land reverts. Willows, heathers, rushes and mosses are the early colonisers, and these largely dictate which other species can be found.

Despite the awful month of May - during which it rained every day - most species are still a bit early this year, so I thought it was time to catch some Spotted Orchids before they reached full flower, when they are not nearly as attractive as they are in the early flowering stages.

This area has Spotted Orchids that cover the spectrum between Common Spotted Orchid and Heath Spotted Orchid, although the closely-related Northern Marsh Orchid that I showed last week is only about 1 kilometre away. These orchids all hybridise freely, and back-cross, so there cannot be any 'pure' specimens left. I can safely predict where I will find specimens that look most like Heath Spotted Orchid, and those are generally on the very edge of ditches, or even in lying water. I strongly suspect that the form of these hybrids is tightly governed by the micro-climate that they live in, and happily refer to all of these specimens as ecomorphs of hybrid Spotted Orchids. To that end I have started to give them a 'parentage percentage', which specifies how much of each of the parents I think are present in each specimen.

Here are a couple that I would place firmly in the Common Spotted Orchid camp, because the front lobe of the flower has a strong tooth:

Common Spotted Orchid

Common Spotted Orchid
The next pair have the outer sides of the flower more rounded and frilled, which sees some aspects of Heath Spotted Orchid creeping in. The spike is also often flatter:
Spotted Orchid

Spotted Orchid

I have included the next shot because it shows the rotation of the flower, which forms upside down, and then rotates into its upright position as it opens:
Spotted Orchid
I think that's my new favourite orchid photograph. Absolutely lovely.

The next shot shows an oddity that appeared in this location about 5 or 6 years ago:

White Bush Vetch
It's Bush Vetch, but rather than the normal blue/purple, it's purest white. When I first saw it, I suspected that some chemical dumping had taken place, but it has spread over the years and has jumped to an area that used to have the normal blue type. It's not unknown for blue or purple flowers to have white variants, and I'm told that this is more common in the west. Maybe the dampness has something to do with it.

Another few heath species have made returns. The first is Heath Milkwort, with the flower just opening:

Heath Milkwort


And my favourite Speedwell, Heath Speedwell, which forms tall, elegant spikes:

Heath Speedwell

The next two shots show two very closely-related micromoths, each about 5mm. long, and which are both leaf-miners on grasses. The first is Elachista luticomella:
Elachista luticomella
And the gorgeous Elachista argentella:
Elachista argentella

I spotted these ants attending their aphids on Willow:
Ants farming aphid for honeydew

Ants often 'farm' aphids, taking the exuded honeydew back to their nest, and protecting their aphids from attack by other species.

6 comments:

The Weaver of Grass said...

Interesting as usual, Stuart.

I suppose orchids to hybridise to some extent do they? I know that my aquelegia get visited by so many bees and the next year I get the most amazing variations. Does this happen with orchids too>? (Hope this is not too dimwitted a question)

Emma Springfield said...

I always learn so much from your posts. All the photos are lovely.

Stuart said...

Weaver: Yes, orchids hybridise. It's quite complex, with a few recognised hybrids to be found e.g. Frog x Spotted, Spotted x Marsh, Bee x Fly, etc. But with the spotted orchids, it's very complex. Heath Spotted and Common Spotted form what I think are two ends of a continuous spectrum. Maybe we're seeing a new species evolve or maybe it's one species with features which vary according to soil type and/or humidity. Genetics hasn't thrown as much light on this area as we had hoped, the biggest surprise being that Frog Orchid is much more closely related to the Spotted orchids than had previously been thought, and it might actually be an ancestor of them all. Beware that there are other opinions out there.....;)

Gill said...

I agree entirely with Stuart about the common-heath spotted orchid continuum, and I suspect the marsh orchids are also part of the same "hybrid swarm" - I see so many intermediates.

Gill said...

Forgot to say that shot of the milkwort is a cracker. I have trouble telling heath from common milkwort sometimes - maybe they hybridise too?

And that little white moth is indeed gorgeous.

Stuart said...

Gill, I only need to worry about Heath Milkwort and Common Milkwort on my patch. I only find Common on Limestone, and it's noticeably larger than Heath.

Hybrids......ecomorphs.....