I have three established Dogwoods, three different species, planted twenty years ago, morning sun, shade in the afternoon. Great growth, no disease.

Trees are crowded, no recent pruning.

I need advice, Should I start selective pruning with the goal of creating more canopy space.

thanks

If the dogwoods bloom well, I would not prune.
If you prune, you provide entry points for fungal diseases to enter. That is a fine line to walk.

Regular pruning is only nessecary if you're looking to keep it (confined) in a particular way (like heding/topiary) or to keep the wrong tree in the wrong place 'in check' (aka, continuously mutilating it haha).

On the other hand, if you're allowing a natural growth habit to its full potential, pruning needs to be done only on these occasions:

* dead, dying or diseased tissues
* crossing branches
* any branching that might in the future pose a threat to either the plant itself or third parties (a person getting a heavy limb on their head) which might include:

- uneven distribution of first order branches on the trunk (they should NOT all grow from the same reference height on the trunk like a rosette, but ideally far enough apart in an upward spiral)
- two or more branches growing against each other (the bark in between them will never fuse and can lead to rot)
- more than one dominant leader
etc