Black Firs & Cranberry Bog

Black Firs & Cranberry Bog

One of a series of nationally important peatland sites which makes up the meres & mosses of Cheshire, Staffordshire and Shropshire.

Highlights

• There is relatively easy walking around the woodland at any time of the year. This part of the site was drained in 1800's. See if you can spot the unusual concentric ring pattern of drainage ditches.

• Visit in summer and see if you can see one of our most uncommon and largest ferns, Royal Fern – frequently planted in gardens - seen here in its natural environment.

Created by glaciers,,,,,

Designated as a Site of Special Scientific Interest and a Ramsar site, Black Firs & Cranberry Bog is one of a series of nationally important peatland sites that have developed in natural depressions, caused by ice-sheets which covered parts of Cheshire, Shropshire and Staffordshire some 15,000 years ago.

Cranberry Bog is an outstanding example of a Schiwngmoor basin mire.  A ‘lawn’ of Sphagnum moss formed over a kettle-hole lake which was created by the glaciers. About 7,000 years ago Black Firs was probably a shallower lake, some 2m deep. Over time the open water would have gradually become vegetated with tall herbs.

Drained by man.

Maps from the 1800’s show the complex pattern of ditches which were dug around Black Firs so that the site could be drained and planted with trees. Although there are some mature trees from the original planting the woodland has become more ‘natural’ in recent years with species such as alder, oak, birch and sycamore. Some indication of the former fen vegetation can be seen along some of the wetter ditches which retain water for much of the year. These wetter areas support plants like yellow irises, Royal fern and the rare fine-leaved water dropwort. Water violets have been recorded in the past.

Cranberry Bog – A well kept secret!

Cranberry Bog has been less affected by historic management. The sphagnum lawn still exists and a small area of open water, Black Mere, is the remnant of the former kettle-hole lake. The lawn itself supports the characteristic plant which gives this part of the site it’s name – Cranberry. Other very rare plants include the insectivorous sundew, bog asphodel and white beak sedge.
Unfortunately due to the hazardous and sensitive nature of this part of the reserve it is not open to the public.

Quality versus quantity?

Black Firs and Cranberry Bog is one of the Trust’s most complicated and least well understood wetlands. Over many generations man has developed great skills and expertise in draining wetland sites so that ‘waste’ land can be put to productive use. Successful historical drainage at Black Firs and Cranberry Bog threatens the diversity of plants and animals, and the ability to return the site to it’s former glory is less well understood. Black Firs continues to dry out and the remaining wetland plants are in decline. A deep ditch around the edge of the reserve drains water from adjoining land and takes run-off from roads and septic tanks and the water quality may potentially adversely affect the reserve. The hydrological link between Black Firs and Cranberry Bog is unclear. If we raise water levels at Black Firs will we end up flooding Cranberry Bog with poor quality water? The Trust is working closely with Natural England to monitor the site and develop plans for it’s long-term protection.

One mans plant is another mans weed!

Visit Black Firs in summer and you can’t fail to notice the Himalayn Balsam that growns along the ditches. Himalayan Balsam is an annual plant which was introduced to the UK in 1839 and is now naturalised, especially on riverbanks. Each plant can produce up to 2,500 seeds and it is spreading prolifically across the countryside. Because it can tolerate low light levels it can outcompete other plants and tends to shade out other vegetation. Himalayn Balsam was planted on land around the reserve in the 1970’s to provide a nectar source for honey bees. It is now an annual management task for volunteer to hand pull the plant to try and prevent it spreading onto the more sensitive parts of the reserve.

Do your bit to help!

More than 94% of the UK's lowland bogs have been destroyed or damaged through peat extraction for use in gardens. Help conserve this unique and fragile habitat by asking for peat-free compost at your local garden centre.