japanese maple leaves bad

ok i have a problem with my young japanese maple tree...the leaves are just with tiny holes ..not all of them but some.i don't know if its due the recent rainy days,or sun (its exposed around 5-6 hours afternoon) on the sun.Or its just some disease or insects.i will post image for someone to identify  .
There is no visible problems all over the tree.

url=https://servimg.com/view/19218085/5][/url]

https://i.servimg.com/u/f18/19/21/80/85/20150714.jpg

Looks like some sort of insect is chewing holes in them to me.

Beetles. If you were in my area, it would be Japanese beetles. They won't kill your tree.