If you know, you know… Bend the inflorescence of Orange Foxtail (Alopecurus aequalis) over and check that there really are no awns. A really nice thing to find in the drawdown zone of a pond.

Pleased to announce my new paper: Herbarium specimens spanning nearly two centuries revealed striking ecological & geographical differences between two ploidy-defined subspecies of Eleocharis palustris in Britain. Ploidy & genome size could help explain them. doi.org/10.33928/bib...

At Wimbledon Common today doing surveys. I remembered seeing a remarkable number of old Starfruit Damasonium alisma herbarium sheets from Wimbledon Common in the Natural History Museum collections. I loved how the plants that were virtually all seed and few leaves. Date was 17/8/1869.

I thought these ponds were meant to be boring today! A massive patch of enormous Glaucous Crystalwort Riccia glauca rosettes on the drawdown at Dagnam Park, NE London.

After a succession of fairly uninspiring ponds, this was rather nice. Huge amounts of Blunt-leaved Pondweed Potamogeton obtusifolius, co-dominant with Elodea nuttallii and carpeting the bottom of one of the large ponds at Swanholme Lakes.

Possibly new Iberian altitude record for Limosella aquatica. Today at Embalse de Casares de Arbás, León, I found Limosella aquatica at 1,288 m, slightly above the highest Iberian record I've so far been able to trace in the literature (1,278 m at Camporredondo). It was growing extraordinarily well!

Up on the Picos de Europa and "wasting" the day at Lago de Isoba before the total eclipse this evening. Picnic packed, beer & wine chilling, & heading uphill for a good view. Shoreline of Carex rostrata, then Potamogeton, then Chara vulgaris. Galician Common Frog sheltering in the shade.

A huge submerged fringe of Juncus bulbosus in a quarry pond. Meter-long shoots formed a dense underwater canopy with no other submerged aquatics. We often think of it as a small rush of wet heaths & pond margins, but in soft, oligotrophic waters it can develop into extensive submerged stands.

Anyone out surveying today? Surrey. 35°C heat, a Sparrowhawk landed beside me at a pond, looking exhausted. It drank, stood in the water to recover, & then started watching newts in the shallows which were swimming through the Stoneworts (N. flexilis agg.). Phone gave up in the heat after that.

Algal succession in a New Forest stream. First came the Planktothrix isothrix bloom (not good). Then Cladophora glomerata. Now Characium sp. colonising the Cladophora. Even in drought, these streams remain remarkably dynamic, with one community paving the way for the next. #phycology

#StillFlowering Streams in the New Forest are drying down after a prolonged lack of rain. Unexpectedly, this Lesser Water-plantain (Baldellia ranunculoides) is still flowering in a dry stream bed. Some species may prove to be winners, but what will we lose if these droughts become the norm?

Coral-necklace (Illecebrum verticillatum). Not #StillFlowering. These are seeds, not flowers. This lovely little annual seems to be increasing in the New Forest, perhaps benefiting from the bare ground created by recent drought years. #WildflowerHour

One of my fave finds: Water net (Hydrodictyon reticulatum). A freshwater green alga that grows remarkable net-like colonies that are visible to the naked eye. Each delicate mesh is made up of hundreds of interconnected cells. It's an uncommon species in Britain, but it can be locally abundant.

Bright yellow Marsh Ragwort (Jacobaea aquatica) flowering among Branched Bur-reed (Sparganium erectum) in a New Forest pond. Winter flooding would kill many plants, but not Marsh Ragwort. It has evolved a way of storing energy in its roots, allowing it to cope with long periods of waterlogging.

For #InvasiveSpeciesWeek & #WildflowerHour, a more familiar invader: American Skunk-cabbage (Lysichiton americanus). New Forest. The story: fallen spadix is still packed with seeds, & nearby, a dense patch of seedlings from last year's. Once established, this striking ornamental can spread rapidly.

For #InvasiveSpeciesWeek and #WildflowerHour, here's an emerging threat rather than one of the familiar invaders. Red-stemmed Parrot's-feather (Myriophyllum rubricaule), not better-known Parrot's-feather. Introduced through the aquatic plant trade, it has already established in a New Forest bog.

A nice surprise in the New Forest yesterday: Brown Beak-sedge (Rhynchospora fusca). It was growing in a pond where the reed had been cut the previous autumn, and the cut stems had drowned over winter. Among the old reed stubble, this uncommon species was emerging into the newly opened conditions.

On a muddy stream margin today: Hampshire-purslane (Ludwigia palustris). Fruits float when mature, allowing them to disperse locally along streams & flooded ground. Light needed for germination, so freshly exposed mud ideal, but unlike some wetland species, drying does seem to stimulate germination.

36°C in the New Forest today. Callitriche brutia ssp. hamulata from a river. The "spanner" leaf tips broad and distinctive. I usually find ssp. hamulata in rivers, while ssp. brutia more in ponds that dry back during summer. I wish I were an aquatic plant today. 🌿

A hot day for wearing waders today, but pleased to find a member of the Ranunculus penicillatus complex in a river. An intriguing New Forest record. The taxonomy is complex, but it is certainly not R. penicillatus subsp. pseudofluitans. 🌿 Heat rash on my ankles, and a long drink afterwards.🧉

For #WildflowerHour: Waders on and out into the water. Spiked Water-milfoil (Myriophyllum spicatum), a submerged aquatic plant sending its flowering spikes above the surface like the Lady of the Lake raising a sword from the water. #AquaticPlants #Ponds #Botany 🌿💧

Spearwort, Coral-necklace, Pennyroyal, Hampshire-purslane & other New Forest pond/wet species. But the pony is the real story. Without grazing, trampling & poaching by commoners' stock, much of this remarkable diversity would be lost. I'm grateful to everyone who helps keep those traditions alive.♥️🐎

Branched Bur-reed (Sparganium erectum) in full flower today in the New Forest. It was striking that the early-season flowers had failed to set in the cool spell we had, but the current ones are producing fruit.

Very pleased to bump into Narrow-leaved Lungwort (Pulmonaria longifolia) while surveying a stream today in the New Forest. It doesn't seem to spread from seed, so the clump will likely be there when I comeback to resurvey that section. A good marker.

Attractive sedges in the New Forest yesterday. Waders on and out in the water. Cyperus Sedge (Carex pseudocyperus) Bladder-sedge (Carex vesicaria)

Beautiful, serene Lesser Water-plantain (Baldellia ranunculoides) in the New Forest. Moments after taking this photo, I looked down and realised my movements had attracted Medicinal Leeches. At least three were climbing over each boot.

An early morning taxonomy black hole. After discussing Valeriana officinalis agg, I tried to trace how the traditional British taxa fits current POWO treatment. V. officinalis ssp. sambucifolia is now placed within V. excelsa, apparently reflecting the relationship with the higher-ploidy aggregate.

Reconnaissance visit to Old River Lea, Hackney Marshes in search of Water-crowfoots -not found- but revealed Nitella mucronata! I checked it repeatedly over lunch, partly because finding a stonewort in an urban London river seemed sufficiently improbable that I suspected wishful thinking on my part.

Three years to the day after my first visit to Braughing Meads, I revisited the Scarce Tufted-sedge (Carex cespitosa) population. The plants were very much affected by the dry spring.

@ilichenmoss2.bsky.social George Greiff in the BBC News headlines on Sunday morning. A fantastic discovery, and hopefully a way to moderate invasive (INNS) Campylopus introflexus (Heath Star Moss). Well deserved recognition for some very interesting bryological work. 🎉🙌 www.bbc.co.uk/news/article...

Killer fungus discovered that destroys UK invasive plant

A newly discovered species raises hope that some native British habitats could be restored.

bbc.co.uk