Apple Tree pests

Hi
ive had my apple tree since last year, ive noticed some little flys underneath the leaves. the leaves are a little discoloured and a curling over, ive only just started gardening
and wonder if anyone has any tips for me something i can do as i dont want to put any chemicals onto my tree.
thanx
emma x

ive had my apple tree since last year, ive noticed some little flys underneath the leaves. the leaves are a little discoloured and a curling over, ive only just started gardening

thanx
emma x
