Botanical Finds at Colliford Lake, Cornwall - July 2022

This day in early July I went on a field trip to Colliford Lake with the Cornwall Botany Group. We went to find Frog Orchids which appeared in large numbers in the 1980s then disappeared again a few years later, never to be seen again. Of course, unless you look for such plants, you can't say they aren't there. So look we did! Unfortunately, we failed to find any, but we still had a good time.

Here are the highlights from that trip.

Round-leaved Sundews are quite common in Cornwall, but it's not so easy to see them when they are in flower. The flowers are only open for a very short time and often tower over the su dew leaves making photos very difficult, but today we timed it right here. Given the distance between leaves and flowers, 2 photos are usually needed.

Drosera rotundifolia

Marsh Willowherb eluded me in Kent and is on the Kent RPR, unsurprising given that the county is usually so dry, it lacks suitable habitat for the most part. Here in Cornwall, it is still uncommon, but is deemed to be an axiophyte, that is, a desirable plant for that type of habitat, but it is a first sighting for me so I was pleased to see some. It was quite an elegant plant and surprisingly graceful for a mid sized Epilobium.

Epilobium palustre

Trailing St. John's Wort was abundant in places, their tiny flowers dotting the ground.

Hypericum humifusum

Corn Mint was plentiful but easy to miss. Due to heavy grazing, these plants were about an inch or two tall at most. In fact the first I realised there were Mint plants about was the lovely smell that emanated from the ground as we walked over a few. You can see below that the flowers look over large due to the leaves being tiny having been grazed back repeatedly from the ever present sheep around the lake.

Mentha arvensis

Shoreweed was a new plant for me too. The flowers lack petals and this one had a few simple stamens arising from green lanceolate leaves topped with anthers to disperse pollen. Of course, it is an aquatic plant that grows in shallow water and only flowers as levels recede in the Summer, hence its name. With the dry conditions, the water level had dropped considerably, allowing this plant to flower well.

Littorella uniflora

Along the shoreline was another new plant species for me which was Allseed. Once it was pointed out, I saw many clumps of it all over the area. It clearly thrives where there is no competition from other plants.

 

 Linum radiola

When I am on a field trip, I try to learn a new grass, sedge, rush or similar type of plant. It is invaluable having experts to point things out to you, so don't waste the opportunity to question an expert to identify a plant for you. This plant below was Common Yellow Sedge and was quite distinctive as you can see. It was quite common around the lake margins.

Carex demissa

Below is Colliford Lake on Bodmin Moor, with the Summer drought beginning to bite as shown by the water levels. Imagine going in for a swim when the levels were high. You would likely badly cut your legs on those drowned, knarled tree branches, hence why swimming is banned here.

No Frog Orchids found - note how short the over-grazed turf is here.

The last plant I photographed here was a common Selfheal, however, this one was a white flowered variant which isn't so common. But around the lake edges, this white form was quite frequent.

Prunella vulgaris (var. alba)

So ended a great day out. Of course, there were many other plants seen too, but we have to end the blog at  some point. If you want to join a botanical field trip in your county then go to BSBI website and click on "Get Involved" and a map of the UK and Ireland appears. Click on your area and full details will be displayed.

Take Care

Dave