This piece was written by FHV volunteer Pat Kane, pictured above. Pat's a former geography teacher who's been volunteering with us since the early days. There's not much he doesn't know about the terroir of our beautiful vineyard!
Forty Hall is unique in many ways. As a community vineyard we are all aware of the human community that we are a part of. Also, we all know about the mud that sticks to our boots and tools, but we seldom discuss what lies below our feet. The soil composition is central to the terroir, the combination of geography, geology and climate that allows our grapes to flourish and for us to eventually produce wine. It provides nourishment, drainage and a life support system for our vines.
The British Geological Survey records all the publicly available information about the geology of the UK. You can put your postcode in their borehole section and it will display, on their interactive map, the latest survey close to where you are.
The last one done in Forty Hall was in 1972, and the hole drilled down to a five metre depth in the Warren Field. The first meter comprises of Topsoil and Head layers made up of brown earthy clay and flints which we have all seen! The soil in the next meter is called Boyn Hill Terrace which contains brown sand, gravel and flint and heavier clay in the last meter. Below that is stiff, brown, and impermeable London Clay.
This soil structure was laid down 59 million years ago. Then, if we were standing in the field, we would have been on the seabed of a warm tropical ocean. That’s 55 million years before humans were on the planet. The area avoided scarring 10,000 years ago at the end of the last ice age.
You may have noticed the bottom of each field is sometimes flooded and often very wet or damp. The rainwater percolates through the Topsoil and Head and starts to run down the slope. It has difficulty percolating through the Boyn Hill Terrace and it is impossible to penetrate the impermeable London Clay. The water drains down the slope and puddles at the bottom as it flattens out.
This is where the community part comes in. If you look around the fields you will see that it has never been developed; my guess is that it has always been used by our ancestors for agriculture. That means that the soil has never been disturbed below the depth of a plough. So, if you happen to dig down to the lower layers that will be the first time in 59 million years that it has seen daylight. You will be the first human to have ever touched it. How cool is that!!!
Pat Kane
photo: Andy Dunn
Join us for a picnic, live music and a glass of wine in the vines. All for a good cause :)
