What is this?

Hello

Noticed the bark on this chestnut crab today....branches and blossoms seem unaffected but definitely something going on with the trunk.

Lost a crab last year - branches shrivel and died and then it succumbed totally...the trunk looked similar?


Any ideas? Hopefully not fireblight....


Thanks
JOanne

G2V Farm
Zone 5B/6
Gaspereau Valley, Nova Scotia
Chestnut crab by boulderwood, on Flickr
Crab by boulderwood, on Flickr

Fungal options include perennial canker, black rot, and anthracnose. All involve a pathogen occupying a niche. Shift such dynamics with biodynamic tree paste. This looks somewhat like black rot despite an unusual coloration, but it's the dying branch symptom that supports that diagnosis. This is far along but it's possible for such trees to keep cambium connection going for years to the branches that remain . . . provided you be diligent about the clay/manure (or compost) slather every spring. The trunk will prove structurally compromised in time.

Lost Nation Orchard
Zone 4b in New Hampshire