windberry, I read it somewhere years ago, who knows where :-) In all honesty, I believe it was a commercial specialty grower who may very well have a higher standard of production than a home gardener. I do recall growing up that our raspberries did decline in vigor and productivity after a few years and remember my dad periodically replacing some of the plants with more vigorous, new rhizomatous shoots.

Sorry......I missed seeing this earlier.

I find newly planted raspberries take a couple of years to get going. Could the 2 - 3 years have been referring to strawberries?

The agriculturalist told me here in North Florida zone 8B that people do strawberries annually for best productivity but I think raspberries and blackberries do take several years to produce better. I haven't had raspberries long enough to know if they declined or not

@gardengal I am asking because after 15 or more years of very successful growing Raspberries in my garden, suddenly, without any good reason my summer producing Raspberry variety succumbed to a strange disease. The new canes develop seemingly strong and healthy, but instead of fruiting in the second year most of them die during their first winter. Only a few canes live long enough to produce fruit, but they develop strange lumps and break. Unfortunately this yearI had to get rid of my summer fruiting variety. I hoped that may be in your answer I will find a clue to what happened to my Raspberries.
Pictures show my Raspberries before and after.

This may be caused by some kind of boring or girdling insect larva. The newest pest here in Oregon is the tiny Rose Stem Girdler, a buprestid beetle. This would explain the sudden onset after 15 years. The pest finally found your locale. In the case of the Girdler, the canes above the bore point have wilting leaves. If the canes somehow make it through the summer, the damage may become apparent next spring.

Thank you The Logician. Though I didn't see any larvae, I believe, too, that it is caused by some kind of borer, but which, and how it did get here?

The new canes develop perfectly during spring and summer, only they have those swellings with strange markings:

Some canes break in the fall:

but most just die in winter. Those that survived get gradually weaker and eventually die before ripening the fruit. Only a few survive long enough to ripen the fruit. The leaves on dying canes never wilt, they only get yellow.

I have caught several of the adult beetles, but have never found a larva after dissecting perhaps a dozen swollen canes. And I have not seen an emergence hole (the adult beetle chews its way out). As to how they got there, these are all flying insects. Some specialize in certain rubus species, and some even prefer certain cultivars within a single species.

I didn't see any beetles, or beetle larvae, but i probably didn't investigate enough. I dug up my raspberry plants in the fall, but for sure new shoots will sprout here and there in spring anyhow, the roots are everywhere (one of the reasons the plants were doing so well for such a long time!). I will watch them much more closely, dissect the canes and look at them with a magnifying glass. May be eventually I will find out what is going on.