Visit to Collyweston Deeps Thurssday 8th June 2023

It was a bright but breezy and cool afternoon when 17 people met in the layby on the A43 ready to visit the Beds Cambs and N’hamptonshire Wildlife Trust’s nature reserve at the old Collyweston deeps quarry. Immediately inside the gate we met with one of the feature species of the site – Dyer’s greenweed, Genista tinctoria, a bright yellow parasitic plant growing strongly in tussocks and a member of the pea family, and widespread through the reserve. Very close by was a newly emerged specimen of Knapweed broomrape, Orobanche elatior, again a parasite, standing proudly in the sunshine. The second species for which this site is noted was Dodder, Cuscuta epithymum, another parasitic plant, but this has no specific host, living on gorse, and many other types of plant, such as thyme, and in this instance bird’s foot trefoil. It looks like thin, reddish hairy strands, spreading over the surface of it’s host plant, and really hardly resembles a plant at all, since it has no leaves, and no chlorophyll. ( a bit like the hyphae of a fungus). We were too early to see the flowers which sit on the strands singly. An amazingly rich variety of flowering plants, 49 in total, which are listed on the website were discovered. A couple of the highlights were hound’s tongue and meadow saxifrage.

Butterflies were observed too – a small group of tiny delicate brown argus butterflies Arisia agestis, balanced on the wildly waving grass stems , and flitted between them, much to the enjoyment of all concerned, and common blues, Polyommatus icarus, flew across the meadow.

Also recorded were several bird species, including, buzzard, Buteo buteo, red kite Milvus milvus, and sparrowhawk Accipiter nisus, and at the end of the visit we were treated to the sight of a family of long-tailed tits, as they flitted among the bushes. A red tailed bumblebee, Bombus lapidaries, several ant hills, and orthopteran nymphs represented the invertebrates, and the only mammal sighting was a couple of rabbits  sitting in the evening sunshine at the end of our visit. A fascinating reserve – one we should return to soon I hope.

Report by Linda Biddle

Visit to Collyweston Deeps June 8th 2023

Species List


Dyers Greenweed

Knapweed broomrape

Bladder campion

Birdsfoot trefoil

Lady’s bedstraw

Common Knapweed


Germnder speedwell

Common nettle

Salad burnett

Wild strawberry



White campion

Hedge bedstraw


Rock rose

Wild thyme

Hop trefoil

Hound’s tongue

Meadow saxifrage

White bryony


Wild marjoram



Wild parsnip




Sow thistle

St John’swort

Mouse ear hawkweed

Greater Knapweed

Quaking grass

Hoary Plantain

Bulbous buttercup

Common Vetch

Horseshoe vetch

Pyramidal orchid

Clustered Bellflower

Small flowered cranesbill


Cowslip ((seed heads)

Rock rose


Lesser stitchwort

Black medic

Prickly sowthistle






Wood pigeon

Black cap

Carrion crow

Red Kite



Blue tit

Great tit

Longtailed tit


Common blue

Brown argus



Red tailed bumble bee