I found that pink leaves on hopseed trees have 2 different variations:
One showing as "Sakura Leaves" in Waila, other one as "block.leaves..name".
They look the same, same icon, and drop same blockitem: Sakura Leaves (Flowering Cherry)

Same issue with "Redwood Leaves" and "block..NLeaves.name"
"Eucalyptus Leaves", "Hopseed Leaves" also show as "block..NLeaves.name" occasionally.

Natura 2.2.0b1, MC 1.7.10

Ok @squeek502 @progwml6 according to ProfMobius, Waila bug was fixed. https://bitbucket.org/ProfMobius/waila/issue/82/incorrect-leaves-names-in-vanilla-game-and But Natura seems to have different problem.