In the "composting zone" at the Trust's Wimpole Hall property in Cambridgeshire, which demonstrates composting techniques to the public, male staff relieve themselves on a "pee bale" which is then incorporated into compost heaps.
According to head gardener Philip Whaites: "The bale is excellent matter to stimulate the composting process. But male pee is preferable to women's, as it is less acidic."
With a conventional flush using 4.5 to nine litres of water, heeding nature's call outdoors also cut water use at the property by up to 30 per cent, the Trust reckons.
The estate also showcases a "dagging tank" into which the rear end fleece trimmings from estate's sheep are stirred up to produce a liquid feed that is then used to nourish vegetables and roses.
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