I have very old blueberries, 50+ years old. 2 springs ago I noticed the buds were turning brown and dying off on one section of the plant. (This section did get very heavy and was touching the ground while being netted three summers ago.) I pruned out this section last spring and now this spring it appears to be spreading, i pruned out all areas that begin to show signs of browning flower buds. Because of time, developing in spring, im wondering if this is blueberry blight?

Ellyn, thank you for contacting Ask Extension. I'm sorry for the delay in responding.  I'm attaching an article from OSU which may provide more information. I wondered about Bacterial canker. I know you don't have young plants but the description matches your description. And most of the other problems occur later.

When you cut a branch, is the center of the stem green or brown? There is a problem called Botryosphaeria Stem Blight:  Growers can find dark brown-to-black branches that will eventually girdle the stem and cause dieback. When cutting into the infected stem, growers can see brown discoloration inside the stem.

If you could bring a branch or two into the Extension office at 2050 NE Lafayette Ave. we might be able to give you a more definitive answer. Remember:  it is important to clean your pruners as often as possible with a 10% bleach solution or by using rubbing alcohol.

I'm sorry I can't be for specific even with your photos. Below is the OSU article.

Blueberry bacterial and fungal diseases | OSU Extension Service

Susan, Yamhill County Master Gardener