Michael Peverett: Lucky finds

Thursday, July 25, 2024

Lucky finds

Rayed form of Black Knapweed (Centaurea nigra var. radiata), with unusual coloration. Roadside near Beckington, 7 July 2024.

A few interesting plants I've found around Frome recently.

These were on a rough roadside that I decided to explore after seeing a flash of yellow plants as I sped by. It was one of those roadsides that's easy to see from a car but more difficult to walk to, and it turned out that sandals was definitely the wrong footwear: the place was a minefield of dewberry and bramble. The yellow plants (St John's worts) didn't prove particularly interesting, or at any rate I didn't spend much time looking at them, having soon found other things to look at.

This is an unusual coloration of the rayed form of Black Knapweed (Centaurea nigra var. radiata). I didn't even know there was a rayed form. More correctly, the "rays" are the enlarged outer florets, which in the British Isles usually characterize Greater Knapweed (C. scabiosa) and are also rather common on Slender Knapweed (C. debeauxii), but much less so on Black Knapweed. Anyway, the rayed form is a thing, though local and scattered according to the BSBI map. I'd better put this on iRecord.

The normal coloration is below.

Rayed form of Black Knapweed (Centaurea nigra var. radiata), with normal coloration. Roadside near Beckington, 7 July 2024.

The Swedish name for Black Knapweed is Svartklint.

It isn't native to Sweden and is extremely rare, with only casual records except in a few sites in Västra Götaland and Skåne. (Apparently it's relatively common in Norway.)

Information taken from this article in Borås Tidning:

https://www.bt.se/bollebygd/svartklint-en-unik-blomma-i-hultafors/

The usual knapweed in southern and central Sweden is Centaurea jacea (Brown Knapweed, Rödklint), which contrariwise is a rare neophyte in the British Isles.

Anyway, here's some more of the fancy blooms:

Rayed form of Black Knapweed (Centaurea nigra var. radiata), with unusual coloration. Roadside near Beckington, 7 July 2024.

Wild Basil (Clinopodium vulgare). Roadside near Beckington, 7 July 2024.

On the same roadside, some Wild Basil (Clinopodium vulgare).

Included here as a blatant excuse for a link to my post about Keats' marvellous poem Isabella, Or The Pot of Basil.

https://michaelpeverett.blogspot.com/2022/06/the-pot-of-basil.html

... which of course concerns an entirely different species!

Below, the same plant in context.

Wild Basil (Clinopodium vulgare). Roadside near Beckington, 7 July 2024.

Hungarian Brome (Bromopsis inermis). Roadside near Beckington, 7 July 2024.

Still on the same rough roadside, I started to notice groups of a tall grass, showing up as reddish in comparison to the intermingled False Oat-grass.

I didn't know what to make of it, but the consensus of the Facebook group (British and Irish Grasses ...etc) was that it was Hungarian Brome (Bromopsis inermis, aka Bromus inermis).

I was a bit worried about the awns (after all, inermis means "awnless" in the context of grasses) but it turns out that Hungarian Brome sometimes has awns up to 3mm in length, like these ones did. And in the course of later poking about I did indeed find some awnless specimens.

Hungarian Brome (Bromopsis inermis). Roadside near Beckington, 7 July 2024.

Short awns on spikelets of Hungarian Brome (Bromopsis inermis). Roadside near Beckington, 7 July 2024.

Flowering spikelets on Hungarian Brome (Bromopsis inermis). Roadside near Beckington, 7 July 2024.

Leaves of Hungarian Brome (Bromopsis inermis). Roadside near Beckington, 7 July 2024.

Leaves: rather light green, broad, basically flat but shallowly keeled below, midrib raised.

Ligule of Hungarian Brome (Bromopsis inermis). Roadside near Beckington, 7 July 2024.

Sheath of Hungarian Brome (Bromopsis inermis). Roadside near Beckington, 7 July 2024.

The leaf-sheaths were closed (not split), except just below collar.

Stem-node of Hungarian Brome (Bromopsis inermis). Roadside near Beckington, 7 July 2024.

The stems were hairless except at the nodes.

A mainly vegetative patch of Hungarian Brome (Bromopsis inermis). Roadside near Beckington, 7 July 2024.

The grass produces a lot of purely vegetative shoots, with the leaves quite closely packed in a sort of herringbone pattern. In some spots (above and below) I found it subsisting almost entirely as vegetative shoots.

I am not sure if I shouldn't be using the name Bromus inermis instead. According to one scheme, all Bromes (except False-brome) are treated as Bromus.

In the other scheme there are four genera, listed here with some (but not all) of their differences.

Bromus: annuals/biennials with short awns e.g. Soft Brome.

Anisantha: annuals/biennials with long awns e.g. Barren Brome.

Bromopsis: perennials with vegetative shoots,

e.g. the familiar native grasses Upright Brome (Bromopsis erecta) of chalk grassland and the gracefully drooping Hairy Brome (Bromopsis ramosa) of woodland.

Ceratochloa: perennials without vegetative shoots. All species in the British Isles are introductions: e.g. Rescue Brome, California Brome.

Bromopsis inermis is native from Hungary all the way eastwards to China: a basic component of the grassland of the Great Steppe. It has been widely introduced for hay, pasture, habitat regeneration etc. In N America numerous cultivars have been developed, e.g. suited to different growing conditions in the north and south. It is invasive and has become one of the commonest grass weeds in the USA. Much more scattered in the British Isles, where it's no longer used as a fodder grass. Another one for iRecord....

It's a similar story in Sweden where Foderlosta ("fodder brome") was first tried in the 1930s but never really caught on.

Vegetative shoots of Hungarian Brome (Bromopsis inermis), growing through a bramble thicket. Roadside near Beckington, 9 July 2024.

Pale Toadflax (Linaria repens). Frome, 2 July 2024.

Let's go into town.

Here's a dozen plants of Pale Toadflax (Linaria repens) growing out of a concrete tree-base in the car-park of ASDA.

Not recorded before in Frome, yet very familiar-looking to me, I suppose from seeing lots of it in Spain where it's a native species.

I had the same feeling of familiarity when I saw it last summer in Sweden where, as here, it's an introduction. (The Swedish name is Strimsporre.)

https://michaelpeverett.blogspot.com/2023/08/august-around-stockholm.html

Pale Toadflax (Linaria repens). Frome, 2 July 2024.

Cave Hawkweed (Hieracium speluncarum). Frome, 11 July 2024.

On Manor Road trading estate, Frome. The luck in this case is not about finding this glorious patch of furry-leaved Hawkweeds (I've watched it for maybe twenty years) but about finding someone who could actually identify the species. I posted pictures on the Facebook group Wild Flowers of Britain and Ireland, Tim Rich noticed the unusual feature of clasping leaves, and along with the numerous glandular hairs he had it nailed as Hieracium speluncarum, sometimes called Cave Hawkweed.

Records are very scattered, but as it happens I saw a reference to it being seen in the disused quarry at Vallis, just a couple of miles from here. And in the village of Mells (an old record from 1905), which is only a couple of miles further.

Hieracium speluncarum is reckoned an introduction to the British Isles. It's known to occur in urban locations. For example it's apparently quite common on the walls of Maastricht in the Netherlands.

Over the years this patch has been gradually spreading, colonizing stony substrate and low dividing walls. I'd guess there are about 300 plants now, some in smaller patches nearby. There's probably more in areas of the estate that are not accessible to the public.