Use of few or no chemicals makes orchards good wildlife habitat
The National Trust says 60% have disappeared since the 1950s, putting local varieties of apples, cherries, pears, plums and damsons under threat.
It is launching a £536,000 drive to reverse the decline of the orchards.
Their trees provide important habitats for species such as the noble chafer beetle and lesser spotted woodpecker.
The orchards - some with as few as five trees - also offer sources of pollen and nectar to bees, which are thought to be declining partly because of a lack of suitable food.
Pressure from commercial fruit growers has led many small-scale producers to develop their orchards or convert them to other uses.
