In a paper of this kind it would be very easy to be over ambitious and therefore be tempted to go too far in an effort to establish relationships between the physical and the other factors which have influenced the livestock policy of this region. Apart from the complexities of these relationships which make it difficult to determine their influence, there is generally a large gap in our knowledge of the physical data relating to livestock farming. For example it is only fairly recently that we have come to realise the subtle influence that certain “trace elements” have on the health of ruminant livestock, and also the marked differences that exist in the feeding value of grass of varied species according to the type of farming practised.

The intricate pattern of distribution of the Devon breeds of sheep can be broadly related to variations in natural conditions. Some ebb and flow in the popularity of breeds is to be expected as a result of changing economic circumstances. Pre-war, there was wide scale crossing with the Dorset Down and South Down rams to obtain earlier maturity. Since the war, the ploughing-out and the new marketing arrangements for fat-stock have brought a revival of interest in the pure-breeds, but as in other parts of Britain, the change over to dairying, especially in West and Mid-Devon, has been accompanied by a permanent reduction in sheep flocks.

In the decade up to the outbreak of World War II. in 1939, the counties of Devon and Cornwall accounted for nearly 10% of the pig population of England and Wales. It is an exporting area for all classes of livestock, but the preponderance of exports over home consumption is indicated in pigs more than any other class of livestock as the figures in Table I., based on information obtained in a survey into the movements and slaughtering of livestock in 1930, show.*