I have many pinus densiflora in the garden for more than 15 years. Each year, a few branches will die off in spring. Usually adjacent branches will fill in after these dead branches are pruned off. It appears to gradually get worst as the pines age. Is this a disease or a characteristic of pinus densiflora? It does not appear to affect other types of pines in my garden.
I just cleaned up all the dead branches a couple of weeks ago. It appears that the dead branches can be anywhere in the tree and not concentrated in any particular location. I can try to take a pic of any dead branches that I missed when I come back from my cottage in a few days' time.