OPAL Soil Surveys in Porthkerry Park, January 2016

OPAL Earthworm and Soil Survey with Porthkerry Park Wildlife Groups, 16 and 24 January 2016

The Soil and Earthworm Survey is suitable for winter as long as the ground is not frozen.

I organised a survey for the Childrens's Wildlife Group on the 16 January and on that day, of course, there was quite a heavy frost. Undeterred, we found a good patch for a pit on the slope that leads to the main meadow. The slope roughly faces south, any frost had melted by the time we dug the pit. The children were great at going through the soil sample and found altogether 25 earthworms: 20 immature ones, 4 Lobworms and 1 Rosy-tipped Worm. It was lovely to see them being so careful with the worms and really looking after them. We were also treated to the mustard-mixing dance. The children practiced a bit of their observation skills – even male pores were spotted-, reading, recording and taking care of living beings. It was worth getting wet and muddy for.

A week later on the 24 January, the Porthkerry Wildlife Group completed a transect survey of three pits across the meadow. Although it had rained a lot in the last few weeks, the ground was not flooded on the day and the temperatures had been considerably milder.

We dug three pits covering the

1) the slope with trees

2) the wildflower meadow (which has been going for about two summers)

3) the amenity grass (heavily walked on by members of the public)

I was hoping to get

- a first impression which sort of earthworms were present

- any differences in the worm numbers in the three different areas

- any differences in soil in the three areas

Getting started on the first soil sample

The main meadow had historically been used to graze cattle, and is now used as amenity grassland. The area on the amenity grass were our pit was, is well used by members of the public.

The wildflower area was established about two years ago. Yellow Rattle had been included and it had flowered well in the last summer.

The slope leading from the road to the meadow has old, well established trees, e.g. oak and ash, but with enough space for wildflowers to grow between them. The Lesser Celendines had started to flower in considerable numbers in the last few weeks.

Here is a summary of the results:

Soil Survey

	Location	Roots	Rubbish	Pencil test	pH	Texture	Smell	Colour	Fizz test
Slope/ Trees	lots	no	easy	moist	5	Clay	fresh	dark brown	yes
Wild flower	lots	no	easy	moist	6	Silty Clay	fresh	light brown	yes
Amenity	lots	no	easy	moist	5.5	Silty Clay Loam	fresh	medium brown	yes

Earthworms Identification

Earth worms	Immature	Green	Black-headed	Lob	Chestnut	Little Tree	Rosy-tipped	Grey	Blue-Grey	Totals for mature worms
Slope/ Trees	6	1						6		8
Wild flower	29	2						1	1	4
Amenity	9		3	5	3	1	2			13
Totals	44	3	3	5	3	1	2	7	1

Grand Total: 69, Total Mature: 25

Award for tidiest square hole goes
goes to Huw and Steven

The soil in the wildflower and the amenity area was gritter than on the slope.

No deep-burrowing earthworms emerged in any of the pits, after the application of mustard water. The ground was quite waterlogged as we had had a lot of rain and some flooding in the last few weeks. The deep-burying worms, the Black-headed and the Lobworms were found in the top layer and might have moved there as response to the water-logging.

The most immature worms were found in the wildflower area and the most mature worms were found in the amenity area. In the amenity area, the greatest variety of mature earthworms were found.

It would be nice to do some more earthworm surveys in the summer to see if the number of earthworms changes in any way. It would also be interesting to monitor if and how the earthworm numbers and varieties might change in the wildflower and the amenity area over the next years.