Norfolk status First discovered in London, 2002 and has since spread substantially.
First Norfolk record of several million mines on Holm Oak at Thetford. (Lee Gregory, 03/04/11) "The trees were totally infested and it was a job to find a leaf without mines and most leaves having 5+ mines! "
Leaf-mine: Nov - April - A contorted gallery mine with usually several mines in one leaf.
Recorded in 8 (12%) of 69 10k Squares. First Recorded in 2011. Last Recorded in 2015.