Diseased bark in fruit trees

Many of my fruit trees are showing signs of sickness. They were planted four years ago and have been showing these signs for several years. I see it especially in apples but also in plums, pears, even the invincible sea buckthorn.

Any ideas what is causing this?

1. Pesticide residue in the wood chips or leaves that I used for mulch?
2. A trace mineral deficiency? I do test the soil and haven't noticed any serious deficiencies in the minerals I tested for.
3. A disease of some sort?
4. An insect pest?
5. Something I haven't even thought of?

The second picture looks like Canker which is a fungal disease.

Recommended treatment include cutting away infected branches and use of a fungicide.

There are all kinds of recipes for homemade fungicide.  Some are fancy and some a simple.

The one I have used was for powdery mildew and it works.

Thanks, Anne. I think there might be something like canker on the stone fruits. I suppose that might be because the tree is already weakened from the other problem, whatever that is.

I do sometimes apply whey on the trees when we have it. Stefan Sobkoviak of the Permaculture Orchard recommends it as an anti-fungal.