Pear Tree

May also be canker, are there any unusually large brown knobbly areas around the stem of this branch? Canker needs to be cut out and burnt.

Fireblight/pearblight tends to be most prevelent in spring and early summer, especially wet, damp, warm ones. It is a bacterial disease which affects members of the rose family, of which pears are members. You get sprays, but they are best used
when the tree is still dormant in late winter and continued on into spring,
stopping when flower buds form. Prune out the affected areas if possible, cutting back to
clean wood below the infected area. Sterilize your secauteurs
between cuts to prevent spreading the disease.

Thanks to all for their advice. I have taken the tree out.