Douglas Justice's February https://botanicalgarden.ubc.ca/february-in-the-garden-2026 blog is about ex-situ conservation and UBCBG's efforts on behalf of Acer pentaphyllum and A. amamiense, complete with photos from the original locations of the seeds.
We were fortunate enough to see some flowers on Acer amamiense ex-situ during a 2024 TMSBI get-together. I believe this was at Wakehurst. The tree had been somewhat frost damaged. Male, unfortunately, but I believe there are three females in the UK. I don't recall whether there is a female at Westonbirt, but there has been some talk of grafting females onto Acer diabolicum rootstock, of which there is a tiny bit available. -E
