[kybishop]

To expand on this, many states have a large white pine lumber industry. The white pine is highly susceptible to a type of fungus harbored by currants.

The fungus does not spread from white pine to white pine, only from currants to currant, or currant to white pine, so eliminating the nearby currants protects the white pine industry.

[lo_zamoyski]

Apparently this is no longer much of an issue. Quoting [0]:

"The federal ban was lifted in 1966, though many states maintained their own bans. Research showed that blackcurrants could be safely grown some distance from white pines and this, together with the development of rust-immune varieties and new fungicides, led to most states lifting their bans by 2003. Blackcurrants are now grown commercially in the Northeastern United States and the Pacific Northwest. Because of the long period of restrictions, blackcurrants are not popular in the United States, and one researcher has estimated that only 0.1% of Americans have eaten one. [...] By 2003 restrictions on Ribes cultivation had been lifted across most of the states, though some bans remain, particularly on the blackcurrant. State laws are enforced with varying degrees of efficiency and enthusiasm; in some states, officials effectively ignore the ban."

[0] https://en.wikipedia.org/wiki/Blackcurrant_production_in_the...

[genewitch]

they're also available at a local walmart as rootstock. I bought one. If i find a nursery that has it i will buy more, but i like growing "weird" plants that no one has heard of, like soapberries, kumquats, that sort of thing.

[QuercusMax]

In Europe they decided to get rid of the white pines (which are not native) in favor of the blackcurrants.

[tycho-newman]

The Ribena lobby is strong

[genewitch]

I'd probably vote this way if given the choice, too.

[euroderf]

Interesting! Citation?

[pfdietz]

Does it go from white pine back to currants?

[SeanLuke]

Yes.