Old Damson recovery

[Essexboy]

I have on my allotment an old Damson tree, it produced only 2 Damsons this year.
is it possible to recover the tree and get a decent harvest. The tree is approx 8 feet high and 10 feet wide and has a trunk some 10 inches round and quite a lot of Lichen growth indicating some age but looks healthy.
Located Truro Cornwall.
Any advice would be appreciated.

[greenishfing]

Up here in Yorkshire we have had an awful year for stone fruit. My cherry trees only gave a fraction of their normal crop and I thought my plum tree had no plums although actually there are a dozen almost ripe. Ask your neighbours if it usually gives a crop. It might just be down to the cold weather at flowering time.

[nickdub]

Cut out any dead bits. Put down manure on as a mulch in the Spring and see how it does

[Plot70]

This year there was a lot of blossom loss due to late frost.
After setting plums will drop there fruit if they get dry while it is forming.
We have local wild plums and they are good indicators of what is going on.