US social scientist Kenneth Boulding : ‘If you believe exponential growth can go on in a finite world, you are either a madman or an economist’.

Saturday, 26 June 2010

26/6/10: Horsenden Hill - White-letter Hairstreak

A 'holding' catch-up posting so that some more recent ones will make sense ....

LNHS meeting, Horsenden Hill, Perivale, for White-letter Hairstreak butterflies (Satyrium w-album), which were duly observed in their favoured Elm tree habitat. This is was the first time I'd seen the species, and was the main reason for attending this event.

Wednesday, 9 June 2010

9/6/10: Forgotten Roses brighten old industrial site

These roses were a pleasing sight on the derelict industrial site opposite, and festooningh the bridge over the Cray by, Maxim Road in Crayford. Would it be too much to ask that these are not destroyed in any redevelopment? One can live in hope. Fortunately two are on a narrow strip of ground between a pathway and the river, up close to river defence pilings, which might just help them avoid the chop ......

9/6/10: Lovely Legumes congregate on Crayford Rough

On my first visit to this site (22/5/10) I had garnered my first ever record of the Yellow Vetchling (Lathyrus aphaca) - though didn't mention it in that post. I knew straight away what this highly distinctive and uncommon plant was from illustrations in books, having been keen to see it for some time.

Today the Yellow Vetchling was in flower, along with an array of other Legumes - fabulous stands of Tufted Vetch of superb colour, Meadow Vetching, Bird's-foot Trefoil, Lesser Trefoil, White Clover, Red Clover and Hairy Tare - and a worthy subject to top this Crayford Rough picture parade.

Yellow Vetchling in flower

Meadow Vetchling in flower

A patch of Tufted Vetch in flower

A closer view of the Tufted Vetch flower spikes, showing the beautiful bi-colouring of many of the plants here

A clump of Asparagus was a further record for the site.

Insects today included:
- a Latticed Heath moth
- the attractive little Burnet Companion moth, my first ever recording/identification of this species
- a male Banded Demoiselle away from the water
- a male Common Blue butterfly
- a Green-veined White butterfly

Birds noted were:
- a Grey Wagtail
- a male Whitethroat
- a Song Thrush

9/6/10: Hall Place plant finds

In the Barnehurst/Bexleyheath area Meadow Buttercup (Ranunculus acris) seem sto be least frequent of the three common Buttercup species, so I was pleased to see this veritable bed of it (pictured below) down the side of St. Martin's Church on Erith Rd.

At the foot of the slope of Hall Place North, near Bourne Rd, were 2 Fiddle Dock, rather battered by the mowing regime.

Over the road in the Hall Place grounds, on disturbed ground by the 'old' car park, were 3 Papaver rhoeas, Pineapple Mayweed, Lesser Swine Cress, Buck's-horn Plantain and Prickly Sow Thistle.

In the dried up 'ditch' by the dismal new car park running down to the Cray at Hall Place were these two species that I hadn't noted here before:

Orange Hawkweed (also known as Fox-and-Cubs) (Hieracium (or Pilosella) aurantiacum)

An unidentified Veronica species with attractive pyramidal heads of flowers, presumed to be a garden escape

Saturday, 5 June 2010

5/6/10: Stag Beetle over the garden

A male Stag Beetle was seen flying over the garden in Barnehurst at dusk today.

5/6/10: Notable bugs in West Tilbury, and some personal plant firsts

Today a London Natural History Society visit to an old sand quarry in West Tilbury, known for the rich assemblage of uncommon bugs that like the hot, dry conditions here with several south-facing slopes.

In particular, we were searching for species that are associated with Black Horehound and with Common Stork's-bill. This involved a lot of kneeling down and ferreting about under bits of plants pressed closely to the ground.

I wasn't familiar with these insects than, and can't claim to be after the event. Instead I recommend that readers check out the impressive macro photos on bug expert Tristan Bantock's flickr site. Those labelled Essex (Broom Hill) on these pages were found today:

but there are many other pictures in the overall collection that show the beauty and/or fascination of this small world around us that we barely notice, so I would urge readers to have a 'wander' round it.

London Natural History Society members scour the promontory at Broom Hill, Essex, for rare bugs, against a backdrop of the Thames Estuary

As it turned out, I did prove quite adept at finding target species, even though I didn't know what any of them were called. My notes record that, amongst other things, I caught an Arenocoris falleni under Stork's-bill (the first one of the day I think), a species for which Tristan notes this site is probably a first County record.

Other species I noted were:

- the relatively colourful Raglius alboacuminatus
- mating Megalonotus praetextatus
- Asiraca clavicornis, with weird antennae and wide front legs, which is now restricted mainly to the London area and Thames estuary. Pictures and more info here:

Plants included a large number of Scotch Thistles and Slender Thistles, 2 Hare's-foot Clover, Common Bugloss, Fiddle Dock (uncommon in Essex) and Sheep's Sorrel. Plants new for me were the rare Subterranean Clover (Trifolium subterraneum), Bur Chervil (Anthriscus caucalis) a species found mainly in East Anglia and 4 specimens of Silver or Hoary Cinquefoil (Potentilla argentea).

Silver or Hoary Cinquefoil, Broom Hill, Essex

Our route back to the station turned out to be rather circuitous, as we trusted our directional instinct rather than a map, and wound up taking a rather longer route than necessary.

This Milk Thistle (Silybum marianum) was one of several in flower along the south side of the bottom of a hedge at the junction of Church Rd and Cooper Shaw Rd, West Tilbury.

Thursday, 3 June 2010

3/6/10: Renewing acquaintance with Field Eryngo

Field Eryngo (Eryngium campestre) is an extremely rare plant, restricted to a handful of sites in the UK, but fairly common on the continent.

There is a plant at what is now Darenth Country Park which I knew and photographed in flower back in the early '80s. In those days it was under a Hawthorn (I think) bush, in moderate-length grass at the foot of a modest chalk slope.

Today I went out with Mervyn Brown, a champion of the plant here (who is another old wildlife friend I hadn't seen for many years, but who recently made a welcome but thoroughly unexpected appearance at my front door on the strength of seeing something I'd posted on the net ....) to help measure the number of growths and leaf area, and cut back some of the surrounding scrub.

Thirty years on, and the Eryngo clings to its precarious existence, but the whole site has been seriously degraded by excessive rabbit grazing, and only small leaves of the plant (growing up from the rootstock) were present, in an area of pretty bare soil. Mervyn later showed me some seed-raised specimens off this plant in his garden.

More on Eryngium campestre, including photographs , and notes from Mervyn on the state of the Darenth site and cultivation of the plant can be found here:

Tuesday, 1 June 2010

1/6/10: Botany of old Crossness Enginehouse site

Jonathan Rooks, an old wildlife mate from teenage days (who I have recently re-established contact with) is involved with the group restoring the old Victorian pumping house engines and the fabulous, cathedral-like ornate ironwork surrounding them at the 'old' Crossness Sewage Works. He is also keen to preserve and enhance the wildlife value of the site, so had asked me to run my eye over the botany, since some folk are wedded to a strict 'cut the grass' regime and need persuading of the merits of a more relaxed approach ..... As it turned out, there was a bit of a drizzle on, and although he'd brought down his mower to go over the already more formal parts, it wouldn't start :-)

The records presented here include some made from outside the fence, when I was there along the sea wall yesterday.

There wasn't anything outstanding, but there was a good array of species typical of the area, and a few that are less common. But in any case some of these plants are quite showy, and several are good nectar sources for insects. It will be quite possible to mow some areas whilst leaving the margins to grow longer.

Species present in the accessible western end of the site - the part under restoration - included :-

Knotted Hedge Parsley
Germander Speedwell
Several Field Madder in the roadway gutter
Common Poppy (Papaver rhoeas)
3 x Opium Poppy
White Campion
Several Beaked Hawksbeard
Geranium rotundifolium
1 x Geranium pyrenaicum
6 x Shining Crane's-bill (Geranium lucidum) together in cracks in concrete at east end of site (complementing that found further along the sea wall path yesterday), and more round the back around the formal garden
1 x Henbit Deadnettle
White Stonecrop (Sedum album)
1 x Dwarf Mallow
Goat’s Rue (French Lilac)
Hart's-tongue Fern
Several Maidenhair Spleenwort in wall by a downpipe - though this looks to have been repaired, shutting off the source of dampness for the fern

In the large, open, water 'tank' were Flag Iris in flower, 2 kinds of Sedge, Reedmace sp. and
Cyperus alternifoliusUmbrella Papyrus, an exotic houseplant – alive despite the harsh winter!

Species in the eastern section of the 'old' Crossness site, fenced off from rest, and not currently under restoration, included :-

Dogwood by fence NE corner x 1
Giant Hogweed (non-native, needs eradicating before it spreads) x 1
Narrow-leaved Ragwort (non-native)
Ox Eye Daisy
Oxford Ragwort
Black Knapweed
x 1
Ribwort Plantain
Bird’s-foot Trefoil
Bulbous Buttercup
Common Vetch
Common Mallow