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Showing posts with label Dittander. Show all posts
Showing posts with label Dittander. Show all posts

Saturday, 9 October 2010

9/10/10: Erith miscellany includes Southern Green Shieldbug and Jasmine

Continuing my roundabout route home from Crossness, I took in a number of streets in Erith, London Borough of Bexley, that I had not botanised before.

The Sandcliff Road flora included Pellitory-of-the-wall, Green Alkanet, Annual Mercury, Herb Robert, Yarrow, Nipplewort and a single Wild Carrot, the last of these on a bank behind old factories.

Common Cat's-ear and White Clover were in a grass verge on Wheatstone Rd.

My first ever Southern Green Shieldbug (Nezara viridula) - possibly a 4th instar nymph according to LNHS expert Tristan Bantock - was found on Urtica dioica by the fence of a rough grassy area next to disused factories off Sandcliff Rd, by Footpath 18. TQ 50631 78353. A recent arrival in the UK, this species is native to Africa, but has been frequently brought in with food imports. Reportedly widespread in southern Europe, it has been recorded annually in southern Britain since 2003.


Southern Green Shieldbug (Nezara viridula) - possibly a 4th instar nymph - was found on Urtica dioica. This is a one-handed, significantly-enlarged mobile phone camera picture taken in poor light, hence the slight lack of sharpness

In an alleyway between Friday Rd and Alford Rd. were several small Sun Spurge and also escaped Strawberry.

This demolition site on Fraser Rd has been vacant for a couple of years, but used to have a lot more vegetation. It looks like it has been part 'sanitised' by bulldozer simply for the sake of applying a warped notion of tidiness to everything and anything. Can't it be left to the wildlife until proper work begins?

Seed heads of Wild Carrot seen through chain link fence and green plastic mesh present an ethereal, slightly artistic picture of the site margin


Another bit of 'greenspace' destined for the chop - once the economy 'improves', one suspects - is the former Erith Tramways Depot site by Walnut Tree Rd. It ought to be possible to leave a goodly belt of trees round the perimeter, and I hope that's what will happen .......

White Melilot, recorded here last year, was still present on the Tramways Depot site, and Narrow-leaved Ragwort has also found its way to this patch of ground.

I was rather taken aback to see a Red Admiral flutter overhead on the adjoining Cricketers' Close at 17.18, in what were not sunny conditions.

On the railway cutting sides just south of Erith Station and the Bexley Road overbridge a Greater Celandine was noted, also an Asparagus plant. There were a number of Ash trees, and a circa ten feet tall Turkey Oak (Quercus cerris) carrying acorns.

Not having run my botanical eye over Queens Rd. before, this Jasmine (probably officinale ) growing out from under several trees (left foreground) and over the railway fence just past the Avenue Rd. footbridge, was most surprising. Given the location it seemed unlikely that it had been planted, but I have never seen it as a garden escape before.

Further down the line there was quite a lot of Elm.

There was Spotted Medick on Thanet Rd, lots of Buck's-horn Plantain at Boundary Street and a Greater Celandine behind the derelict 'Style and Winch' public house on Northend Rd. Black Horehound was by a housing estate here.

It was by now rather gloomy, but I was cheered by coming across a fourth site in the Borough for the uncommmon plant Dittander - on a mound at the south-east corner of a grassy area by flats on Northend Rd, next to a garage/petrol station. This neatly fills in a gap between my other three locations which are Thames Road Wetland, part way up Thames Rd towards the junction with Northend Rd and then the south east corner of the Erith Quarry site.

A Senecio cinerea above a retaining wall at the top of the hill on Colyers Lane appeared to be outside the garden boundary, and had the look of an 'escape', though it might conceivably have been planted. There was also a lone Narrow-leaved Ragwort here.

Tuesday, 13 July 2010

13/7/10: Brookweed and Little Grebe amongst new records on Thames Road Wetland

More recording either side of some Cray Riverkeepers work.

On the way down to the Cray an adult Asparagus Beetle was seen on Asparagus in Eversley Avenue, and larvae on Parkside Rd.

A clump of Tansy was noted on the 'rough' off Perry St. roundabout, in the Thames Rd/Gascoyne Drive section, a new record for me here.

22 Starlings were seen on roofs on Barnes Cray Rd.

Dace and Chubb were seen in the River Cray by Footpath 106. Amongst the marginal plants recorded were Branched Bur-reed (Sparganium erectum), Reed Sweet Grass and Reed Canary Grass in flower.

Insects about along FP106 and By-way 105 included a couple of Red Admiral, Gatekeepers, Banded Demoiselles, lots of Blue-tailed Damselflies and also a Large Red Damselfly ovipositing.

Next stop was the Thames Road Wetland (TRW). On the western section of the Sewer Embankment was a Black Knapweed, which I don't recall seeing here before (but I may be wrong - I'm way behind on spreadsheeting my records to make them quickly accessible ..... ). There were Cinnabar Moth caterpillars on Common Ragwort. A Large White Butterfly was seen further along, and 2 adult and 2 juvenile Goldfinches flew onto a shrub.

Black Knapweed and Common Ragwort on the Sewer Embankment by the TRW

The TRW is glimpsed over a clump of the uncommon plant Dittander (Lepidium latifolium), a mass of which were pouring forth their frothy white flowers along the Sewer Embankment

Looking out over the Thames Road Wetland, birds on the 'lake' (the deeper, open water at the eastern end of the flooded area west of the Wansunt) were 2 adult and a couple of juvenile Coot and a new record for me on the site of Little Grebe (Dabchick), of which there were 2 adults and 3 small young.

A couple of the mildew-feeding 22-spot Ladybird species down in the TRW 'bowl' were also a new record here.

At one point I was trying to get close to a flying Dragonfly, in order to get an ID, when it was grabbed from among the Reedmace by a House Sparrow which disappeared into the Thames Rd shrub beds with it.

From this side of the site I was able to pick out 4 Gadwall somewhat hidden on a small grassy 'island'.

Wild Mignonette (Reseda lutea) was in flower on the flat, dry, ground up next to the Thames Rd fence.

Next I checked out that part of the site to the east of the River Wansunt. There were a few Purple Loosestrife in flower here, some Gypsywort and 8 Celery-leaved Crowfoot (Ranunculus sceleratus) in flower in the damp margins of the drying pool.

Dittander is now down in the bowl proper, on a corner of the easternmost pool, next to Branched Bur-reed which only seems to be at this end of the site so far, and is a new record for the 'bowl'.

Branched Bur-reed in flower on the TRW

A further new record for the site was a single Greek Dock which, oddly, was growing in the water.

A Goat's-Rue was also found down in the bowl.


The pool on the eastern fringe of the flooded area, east of the Wansunt, is shallow, its winter extent shown by the thin Rushes in the picture above

In the drying, but still quite damp mud here (with water pooling in old horse hoof-prints), yet another new site record was obtained in the shape of 15 flowering plants of Brookweed (Samolus valerandi). This is a member of the Primula family and has small, white flowers, with notched petals. This is the first time I've come across this species anywhere. It is reported to now have a rather restricted distribution in the UK, so this is a good find.

Brookweed (Samolus valerandi) on the TRW - a species completely new to me

Thursday, 10 September 2009

9+10/9/09: In and around the River Cray

Two consecutive days out by and in the River Cray with the Thames21 volunteer group and the indefatigable Riverkeeper, Ashe Hurst, a man who appears to have an inexhaustible supply of 'Tales of the Riverbank'.

See

http://www.thames21.org.uk/events.html

for events listing. More recruits always welcome.

On the Tuesday we spent a bit of time watching an Environment Agency team electro-fishing a sample length of the river to see what species were present, and to measure all the fish caught. Amongst other things, a fair-sized Pike was observed. Later we did some wading and measuring just north of the upriver bridge in Crayford town centre for the installation of flow deflectors (there were some fine patches of Liverwort just above the waterline on old stonework here). The purpose of these is to help clear the build up of silt under one side of the bridge, and to provide areas of differing water speed to create a greater variety of conditions for wildlife.

On Wednesday we heaved a large number of lorry tyres dumped on the bank by Crayford industrial estate across the river, then down a footpath to a skip. After that it was a case of wading up and down the river picking litter, including quite a lot of cans etc. embedded in the riverbed. A selection of clothing prompted speculation about the likelihood of a dead body or two ....... There were also several plastic bags-worth of takeaway establishment menus that had been dumped in riverside vegetation, presumably by deliverers who didn't bother to do what they were paid for.

A Chinese Mitten Crab was found under the bridge arches at the upstream end of Crayford Riverside Gardens in a bag containing a rotting display stand of some sort. Thought to have arrived in ship ballast, this species burrows into riverbanks, eventually causing their collapse along with any reeds or other vegetation above, which can diminish suitable habitat for endangered Water Voles.

Whilst cleaning up the river, water plants such as Watercress, Brooklime, Water Mint, Water Forget-me-not, Fool's Watercress and Water Figwort were seen.

My favourite plant in this sort of habitat - for the name at least - is Trifid Bur-marigold, of which there was a lot at the Waterside gardens. It looks rather like a Dahlia on a diet, but with rather less conspicuous flowers.

Non-native Giant Hogweed and Himalayan Balsam are troublesome invaders along the Cray, and concerted attempts are being made to eliminate the former and limit the latter.

After all the work, I did a fair amount of additional wildlife recording in the vicinity of the river.

Along Footpath 106 by the river, 'behind' Crayford Way, a pristine Comma, Red Admiral, Painted Lady and Small White were all feeding on the same smallish Buddleia, a sight that wouldn't have merited a mention in my childhood when it was commonplace. A couple of Geranium pyrenaicum were also noted.

I then headed downriver from Maiden Lane towards Thames Road.



A fabulous stand of Purple Loosestrife by the Cray between Maiden Lane and Thames Rd



A rather late-flowering specimen of Dittander (Lepidium latifolium) - with the narrow leaves, foreground - a fairly uncommon Crucifer, seen not far from the Thames Rd bridge

Dittander was once cultivated. Young leaves can be eaten raw or cooked and are said to have a very hot cress-like flavour and may be used in small quantities in salads. The roots can be grated and made into a horseradish substitute.


Various larger Dragonflies were seen but I couldn't get a close enough view for a positive ID. I did, however, get to see my first Brown Hawker (though it's quite a common species) at close range when a female stopped, apparently to lay eggs, on a bit of rotting log emerging from the water up near the Thames Rd bridge.



A rather naff bit of 'landscaping' by the river where the Thames Rd bridge was recently widened

Various native shrubs have been planted in plastic tubes here, but some of the species do not naturally occur in the local area. Rather than doing this and covering the mound with bark chip, which is inevitably slipping away, it would probably have been better - and certainly cheaper - to have left it to get overgrown naturally!

I then surveyed and took quite a lot of photographs of the 'field' bordered by the Cray, Thames Rd, the Slade Green to Dartford railway line and the Sewer Pipe embankment. Thames 21 will be tasked with monitoring and managing this, after it was excavated to below water table level, landscaped for Water Voles and planted up with lots of Great Reedmace, sedges and rushes as a mitigation measure for loss of land to housing nearby. But I'll do a separate 'feature' on this site another time.

I also had a distant view of what was almost certainly my first Little Egret, just west of the railway line in a water body in the field south of the Sewer Pipe embankment.