Posted by Graeme Lyons , Saturday, 24 May 2014 14:26
For the last five years I have looked for the mythical Burnt Orchids that Steve found around ten years ago at Southerham but no one has seen since. Until now that is! Yesterday I started mapping and/or counting the rarer plants of our chalk grassland site Southerham. I was concentrating on mapping Chalk Milkwort and White Horehound. I was going to attempt my annual search for the Burnt Orchids when I met up with Steve at Bible Bottom, I really didn't think we would find them.
Independently, Steve and I both came to the conclusion that Chalk Milkwort seems to grow only on the very best parts of the chalk and could maybe be an indicator for other interesting plants. The Chalk Milkwort is by no means ubiquitous at Southerham like Common Milkwort is, in fact it grows in discrete but diffuse patches that lend themselves well to mapping. In fact the area where the Bastard Toadflax is, is in a Chalk Milkwort area too (but that is too hard to find until it's in flower). I did see some yesterday but only by getting on my hands and knees, I'll go back to do this in a month. Anyway, we were surprised at how little Chalk Milkwort there was compared to what are memories were telling us, I believe this is the fault of our memories though and not a decline in the plant and demonstrates the importance of detailed monitoring. Memories change the more you access them, Excel files don't.
Right at the top of the slope, way further up than I would have thought to search, we found the first patch of Chalk Milkwort we had seen in all the huge area of Bible Bottom and ten metres beyond this I walked right up to a single Burnt Orchid. Suddenly there were four more and then Steve found another seven. Despite a thorough search, we didn't find any more. Twelve specimens tallies with what Steve recorded all that time ago. Another point this illustrates is the importance of taking accurate grid references, we only ever had a six figure grid reference for the old record. Now we can monitor these plants and keep an eye on them. A brilliant and unexpected end to the week! Not the best photo in the world but I don't care as this is evidence that we have our own Burnt Orchids!
Now, I was originally going to blog about the differences between Chalk and Common Milkwort so here goes. In the image below, the top plant is Common and the bottom one, Chalk Milkwort.
With Common Milkwort, the stems are usually a little longer, the leaves larger and more pointed but more importantly they are smaller towards the stems base and are alternate all the way down. With Chalk, the leaves are a little smaller and blunter and get larger towards the base where there is a 'false rosette'.
However, they can be separated on jizz and colour with experience. On the Lewes Downs, Chalk Milkwort is usually (95%+) white with a hint of blue and only occasionally electric blue as is the typical form (both are shown in the photo below). Common is white, pink or violet but is rarely the electric blue-white of Chalk. My camera doesn't quite do this shade of blue justice.
In addition, the flowers are arranged differently, much more congested but more neatly arranged all the way around the stem (first image below) while Common looks messy in comparison (second image below shows Chalk Milkwort in white and Common in pink). Chalk also appears more upright and forms denser patches of flower spikes about the size of a dinner plate whilst Common appears more scattered. With experience, it's quite easy. What really struck me yesterday though is that Chalk Milkwort is restricted to the most floristically rich CG2. Go and have a look now, as Chalk Milkwort is an early flowerer and will be over by mid summer.