What is Juniper (Juniperus communis)?

Juniper is one of three conifer species native to the UK. There are two subspecies: the dwarf or prostrate juniper (subsp. nana) is a low growing, matted shrub with elongated berries, mostly confined to coastal and mountain areas. In the Durham area we are concerned with the 'tree' juniper (subsp. communis), which can be upright, but (just to confuse things), also grows on the Durham coast in prostrate form.

Juniper is an important food plant for many invertebrates. Thirty-five insects and three mites are specifically associated with juniper and the berries are eaten by a number of birds including thrushes, fieldfares and waxwings.

Why is it dying out?

The once extensive stands of juniper in Durham's uplands are dying out. New plants are not establishing in the surrounding grass. Not enough is known about the right conditions for Juniper propagation but it seems that under grazing prevents seeds from ever reaching the soil whilst overgrazing prevents young plants from establishing.. Ideally, Juniper probably needs some ground disturbance followed by periods of low intensity grazing in order for it to regenerate naturally.

Analysis of charcoal from Weardale shows that juniper (although present in Weardale woods) was not used by the iron-smelters as a component of charcoal. One possibility is that the present stands of juniper are remnants of former, more diverse woodlands, which were cleared for charcoal leaving the unwanted juniper behind. Perhaps it initially managed to colonise the disturbed ground and spread out, but conditions have changed and the juniper is only able to regenerate periodically when conditions are right.

What are we doing?

The Durham Biodiversity Partnership is doing two things to try and reverse the decline in local juniper populations. Firstly we are establishing a stock of locally sourced plants. Seeds are being collected from known local stands and being grown on by Trees Please. Once grown the plants will be available to partner organisations for planting out in the Durham area.

The second activity is the planting of new or expanded juniper woodlands and the inclusion of juniper in new planting schemes for upland oak woodland.

New Juniper sites

Sites chosen to establish new juniper woodlands are in the west of County Durham in the Pennine dales of Weardale and in Derwentside.

As part of the partnership's involvement in the Mineral Valleys Project and with additional financial assistance from CDENT (County Durham Environment Trust) we have planted over 2000 juniper plants of Cumbrian or Durham provenance on sites near Waskerley Reservoir and at Durham Wildlife Trust's reserve at Hedlehope Fell. More plants of local provenance will be available for planting schemes from 2008 onwards.

Other partners have also been busy with Juniper planting during the last few years, particularly Natural England in Teesdale and Durham County Council on a number of their reserves. Smaller landowners such as Harehope quarry and volunteers from local primary schools, Northumbrian Water, the Wildlife Trust and the BTCV have all helped with the planting effort.

More information from info@durhambiodiversity.org.uk

Juniper Action Plan