Sunday, 23 August 2009

Cut-leaved Germander and Ground Pine

Back in January Steve Gale kindly welcomed my new blog with a comment about a number of plants we are lucky to have growing in this area, including Ground Pine (Ajuga chamaepitys, left) and Cut-leaved Germander (Teucrium botrys, below) both of which are nationally rare. Well, yes and no!

He was I am sure, referring to a small piece of chalk grassland just to the south of Banstead Woods called Fame's Rough, a cracking place for both wild flowers and butterflies. It has an interesting history which essentially boils down to the fact that in WWII the field was ploughed to grow crops (unsuccesfully) and for a few years after Cut-leaved Germander (among others) was common having only been previously recorded as an infrequent arable weed in the area. After a few years it disappeared only to reappear en masse when the land owner was persuaded to ploughed a strip of the field.

For the next 30-40 years a new strip was ploughed every five or six years and the cycle repeated, often with both the above and many other ruderals (colonisers of disturbed ground) growing in huge numbers. Obviously the seed of these species is quite long-lived but they have little capacity to compete with other plants.

For the past 10-15 years the ploughing has stopped and the field started to scrub over, a couple of years ago the scrub was cut back and a test was started to see how much soil disturbance was required for the germination of these species to occur. A number of areas were dug/scarified to varying degrees but not ploughed! The results were fairly disappointing with a few plants of both species appearing but no great numbers.

Last year a larger area was lightly rotovated and a on recent visit I failed to find any plants of either species, so it appears it is ploughing or nothing. Hopefully this will be tried soon.

The two plants are interesting as well as rare, Cut-leaved Germander occurs at probably fewer than ten sites in the country and Ground Pine at only 32 sites since 1970. They are fairly closely related members of the Labiatae or Lamiaceae (or whatever), the mint family. but are instantly recognisable as they are members of the only two genera of that family in this country that have very little or no upper lip as the picture of Teucrium botrys below shows. You can read more about Ground Pine in an excellent dossier produced by Plantlife.

The interest on Fame's Rough does not end with these two species, it is a joy to behold from spring through summer with many chalk specialist plants including orchids and is always well worth a visit.

Finally, to get back to Steve's comment, yes, I am sure the plants are still there, if only as seed but; no, you'll be lucky to find them this year. I should point out the photos were taken a couple of years ago.

Tuesday, 18 August 2009

A knotty find.

Strolling around Park Downs the other evening I noticed a small white flower (above), on the path, just another Purging Flax I thought, but no it was larger than that (probably why I noticed it) although still less than 1cm across. On closer inspection it turned out to be the flower of Sagina nodosa, Knotted Pearlwort. This is a very delicate plant with terminal flowers on stems that bear very small linear leaves clasping the stem that give the "knotted" feel when you run it through your fingers, you might just be able to see it in the picture above. Try getting an in-focus picture of the stem.

If you look in any British flora it will tell you something along the lines (to quote Clapham, Tutin and Warburg, I live in the past) "Frequent in damp sandy and peaty places throughout the British Isles". So what is it doing on dry chalk downland?

In fact in Surrey it seems it does things differently. In Lousley's Flora of Surrey (1976) it is described as very rare, only recorded at three sites in the recent past, two of which were on chalk including Banstead Downs up until about ten years ago. As far as I know it was first recorded on Park Downs in the early 1980s about 100 m from where I found it and had not been seen for about fifteen years. It was thought possibly to have been imported with gravel used to repair the path it grew on.

However I remembered that last year I had photographed a small white flower on another path on Park Downs and promptly forgot all about it. I dug it out and sure enough there it was (below) Knotted Pearlwort, so back to Park Downs and last night I found it again in the same place on a path some 100m from the other two sites. The fact that it is still present across quite a large area perhaps that even if it got here by man's hand it can survive quite happily. Certainly not an obligate calcifuge. Of course strictly a non-native in this context!!!!!!!

Later this week I shall inspect Banstead Downs to see if I can find it there. Watch this space.

Thursday, 6 August 2009

Late re-entry - Small Balsam

For a number of non-botanical reasons, I haven't posted for a long time so I have plenty in reserve now I am resuming!!

One surprise this summer came at the weekend when walking in Banstead Woods. In many places there is a good cover of Impatiens parviflora, Small Balsam along path edges. Interestingly it also seems to be one of the earliest plants to be able re-colonise ground after Rhododendrons have been cleared, even so it still takes a couple of years before it can germinate.

It is not a very showy plant only having a small flower, however, close-up (above) it is rather attractive. The base of the petals (and sepals) appear white with red markings with the rest being yellow. The surprise came when I stumbled upon a couple of plants with flowers that completely lacked any yellow (below) being white , the red markings more pronounced! White variants of many species are quite common but I have never seen it in this species, indeed I have rarely seen white variants of any normally yellow-flowered species. Off the top of my head I can only think of Primrose and even that was as a garden variant.

Has anyone else seen a white Balsam?