[Tweeters] So, what are the connections between Birds, a Himalayan giant, spineless cactus, Potato-tomato hybrid, freestone peach, elephant garlic, the Shasta daisy, fries at McDonald's, a mutated potato called the Russet Burbank and the spread of Himalayan blackberries (a hugely successful , invasive species in Western Washington), Mercer Island, a farm for “troubled boys”, Thomas Edison, Henry Ford, and fresh fruit for the masses?—-”The Strange, Twisted Story Behind Seattle's Blackberries : The Salt : NPR”

[Dan Reiff via Tweeters]

 Luther Burbank. 
See the informative article: link below.

And to partially answer JIM‘s question, Birds and other animals, eat the berries and spread the seeds far and wide, every year in Western Washington. Every few years I remove all of the Himalayan blackberry vines and roots from my yard. Birds reseed the blackbirds in my yard every year and new roots and vines have to be removed a few years later.
So yes, birds eat blackberries.

When I was in undergraduate school, studying environmental sciences, one of my proposed research projects was to study the lead content of blackberries from bushes near roads, where people commonly pick them. At that time gasoline was leaded and I was concerned about the possible lead content in those blackberries,  among other pollutants from motor vehicles that may have been absorbed by the plant Or adhered to the surface of the  Himalayan blackberry plants and their berries.
The proposal was accepted, but I chose a different topic.
Best regards,
Dan Reiff

The article:

https://www.npr.org/sections/thesalt/2016/08/29/491797791/the-strange-twisted-story-behind-seattles-blackberries



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