These two willows are side by side in I think the Asiatic section of the Alpine Garden. I saw this Salix integra 'Hakura-nishiki' on May 26. It still has its new leaf colouring today. I mentioned last year that it will lose the pink, but I never remembered to check back to see what its normal colouring is. Maybe this year. I was having a hard time finding the label for this very striking tree nearby, but I could have easily made it up - Salix purpurea 'Pendula', which describes it perfectly, with the purple being on the stems, not the leaves. The catkins have black tips, which I read is a characteristic of this species. I only found a single group of four catkins (did not include the two fuzzy ones, which I think were out of focus, not really fuzzy).
I remembered to check back on the Salix integra 'Hakura-nishiki' to see if the leaves had turned. Too early, I guess.