there is a rhyme we used to sing as kids

Here we go gathering nuts in May, nuts in May, nuts in May.
Here we go gathering nuts in May, on a cold and frosty morning.

Looking further, I found out that it should have been 'knots of May' which makes more sense as there are knots of flowers on Hawthorn trees which are also referred to as May trees, and the flowers as May flowers.

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HERE WE GO GATHERING NUTS IN MAY    https://www.youtube.com/watch?v=UeMDX7JUGCE