GREENWOOD
Nature and the neighbourhood
Beside the Path 3
The new unblemished horse chestnut leaves reach down low towards the waist-high white cow parsley flowers beside the path. Later in the year, the leaves will develop the brown blemishes caused by the larvae of the chestnut leaf miner moth, which is a species that has been accidentally introduced to Britain from Spain.
GREENWOOD 
I wondered why there were brown marks on the leaves later in the year. Yvonne
Yes, fascinating really. I did a couple of posts some time ago on my other Jessica’s Nature Blog about this. The caterpillars are so tiny that they can live and feed in the spongey layer between the upper and lowers outer layers of the leaf. https://natureinfocus.blog/?s=chestnut+leaf+miners