Ouch! Sorry to hear that. Beautiful garden. Possibly a heliopsis or a helenium. Helenium Double Trouble might work for you. If you like variegated foliage heliopsis "Lorraine Sunshine" possibly, Tuscan Sun is nice but is probably a little short for what you want.

Oh, I feel your pain. That is just awful. Your pictures are so beautiful, it's a shame to have to disturb and remove anything there.

I was doing a bit of research on sizes of Coreopsis for another thread here, and found Coreopsis Mayfield Giant listed at 2 and a half to 3 feet tall. It is also listed as attractive to butterflies. It sounds like something you are looking for in that it's a yellow flower, the height you are looking for, and it attracts butterflies.

Good luck with your new replacements and sorry to hear about the disease problem.

Linda

Thanks hostaholic and linlily. It really makes me sad to have to remove it.

Buphthalmum salicifolium can bloom from May to September.