E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Cuckoo Oats and Woodcock Hay.
Cuckoo oats and woodcock hay make a farmer run away. If the spring is so backward that oats cannot be sown till the cuckoo is heard (i.e. April), or if the autumn is so wet that the aftermath of hay cannot be got in till woodcock shooting (middle of November), the farmer must be a great sufferer.