In 'Poetry of the First World War, edited by Maurice Hussey, we find: "When we read one of Thomas's nature pieces we are inclined to ask ourselves this: Why is country poetry so frequently naïve? Isn't there room for adult writing on the countryside? Since Thomas was capable of complex thought in such surroundings, why must so much pastoral poetry resemble what the music critic, Constant Lambert, once remarked of the composer Vaughan William,, 'a cow looking over a gate'?"
Personally - having a bit of a 'pastoral mind' myself - I simply claim such 'naïvety' a 'basic human right' which is at the very basis of 'adult writing' with 'complex thought'.
If one needs convincing there's always Thomas's 'A Private':

A Private

BY EDWARD THOMAS

This ploughman dead in battle slept out of doors
Many a frosty night, and merrily
Answered staid drinkers, good bedmen, and all bores:
'At Mrs Greenland's Hawthorn Bush,' said he,
'I slept.' None knew which bush. Above the town,
Beyond 'The Drover', a hundred spot the down
In Wiltshire. And where now at last he sleeps
More sound in France—that, too, he secret keeps.