It seems Rav Kook is known for his healthy eating habits, insisting on fresh foods without preservatives and other chemicals. 

Rav Kook has spoken out before against the eating of dried and sweetened fruits on Tu B'Shvat calling them poisonous and saying one is not allowed to buy them. This is due to the chemicals in them. Rav Kook has added that one should throw such dried fruits into the trash and it is not considered "bal tashchis" - being wasteful.

To that end, Rav Kook has now paskened that if one is going toe at such dried fruits on Tu B'Shvat (or any other time) the appropriate bracha for these fruits would be Shehakol and NOT Haetz as they are not considered fruit. One who buys such dried fruits is assisting in committing a sin and these destroy the world and our health.