Douglas Justice's August 2017 in the Garden posting was entirely about maples at the botanical garden. There is a link to the blog article, and my photos of most of what was mentioned, at August 2017 in the Garden. There are also two photos of Acer pentaphyllum and a link to Douglas's July Blog, also about maples, at July 2017 in the garden. These are in the Talk about UBC Botanical Garden forum, and I'm posting the link here because I think most of you probably wouldn't think to look there for an article about maples.
