Q.plum tree diseases
Our old plum tree (after a bumper crop last year) this year looks to be diseased- with hardly any plums. The leaves are turning brown, curling up and dying early with many small holes apprearing first. I am struggling to find out much about diseases of plum trees at our local garden centre and wonder if you can help. The leaves are also overed top and bottom with small white flecks. Thank you – Cambridgeshire UK

Here is a link with common Plum Tree diseases.
https://www.gardeningknowhow.com/edible/fruits/plum/plum-tree-diseases.htm