Sid Valley Wildflower Survey November 2021

This is the eleventh and penultimate update to the year-long survey of the valley’s herbaceous plants being carried out by volunteers with the Sid Valley Biodiversity Group.  The group is compiling a modern list to compare with the list of species drawn up by local doctor and amateur botanist W.H. Cullen who conducted a survey in Victorian times that was published in his book Flora Sidostiensis in 1849.

Meteorologists count November as the last month of autumn and there should be very few herbaceous plants still in flower.  Sidmouth has continued to stave off oncoming winter with most days in the first three weeks hitting temperatures above 14^oC.  This has allowed the volunteers to find 54 species (see below) still in flower, although actual flower numbers were very sparse.  As explained in the October report, plants produce flowers to produce seeds and those species that rely on flying insects as pollinators rarely flower this late in the year because there are very few insects still flying.  The Sid Valley’s sheltered climate allows some insects, for instance this Drone Fly photographed on Salcombe Hill on 14^th November, to carry on flying and feeding well past the summer peak. 

If you compare Sidmouth with my former home in Derby in the middle of England, you can see that our summer temperatures are similar, but Sidmouth’s autumn and winter are warmer (Fig.1).  Two degrees may not seem a lot but, to accumulate that over a month’s data is a significant difference.  Picking February 1^st as an example for a longer term comparison (Fig.2), you can see that Sidmouth does not get as cold as Derby.  As a side issue, both appear to be on an upward trend, but a single day’s readings, even over 13 years is not sufficiently robust evidence to confirm climate warming.

There were no new species recorded in November but, once again, some species seem to think the combination of day length and temperature indicates the arrival of spring and they have come back into flower. 

The Scentless Mayweed is growing in a patch sown with wildflower seed mix in the Knapp and has been flowering for some time, but the Scented Mayweed is a genuine wildflower growing, as it should, in a farmer’s field among the wheat stubble.  The Buck’s-horn Plantain, a seaside specialist, has persisted on and around the Millennium Walkway all summer but not in flower.  The warm start to November triggered a second burst of flowers.  In the same way, Wavy Bittercress has been present in the cracks and crevices around the town centre walls all summer but not in flower.  It is now putting out its tiny four-petalled white flowers in the hope of a passing solitary wasp pollinating them.  December may see more species starting over again in their annual cycle.

December will see the end of this phase of the project.  A summative report will be published early in 2022 with more details about Cullen’s list, and a list drawn up by local naturalist Bob Hodgson who used to provide displays for the museum in the 1970s and 80s.  Next year, we hope to extend the survey to cover the many grasses and sedges that populate the valley, and the non-flowering ferns and fungi.

Ed Dolphin

Herbaceous species recorded flowering in the Sid Valley area October 2021

* First record for several months