Hi everyone - and Happy new Year! There's a discussion going on on a bonsai forum about field maples that sometimes show a kind of cork brak on young branches, a bit like the wings on Euonymus alata. Some say "it happens when the shoots are allowed to extend vigorously (on the extending branches, not the trunk)", but I'd rather say that "it's not that uncommon in dry, sunny spots. They also tend to have more deeply cut leaves than others, and I even wondered if it was not a subspecies or at least some genetic variant. I've seen quite a few in the south of France, and I've got one that self-sowed itself at the bottom of my stairs." "this one gets the sun from morning till at least 5 o'clock in the afternoon, is facing south and is growing against a concrete pillar." EDIT: a new post just makes me doubt: Wee Trees Bonsai Help Forum Advice for all • Login What do you think? Here is photo from August 2013, and two others taken today:
I've seen it a few times, but not quite as conspicuously as in your pics. I have seen the suggestion that corky wings on twigs like this is an adaptation to make the shoots less palatable to large browsing mammals - the bark is very bitter and unpleasantly dry-powdery when chewed. Corky bark wings occurs in a variety of unrelated, but often not-very-tall species, which would tie in with discouraging browsing. Worth bearing in mind that when these species evolved, there were still abundant large browsers everywhere, even though they are mostly extinct now.
Hi Alain, and happy New Year. Like you I've seen this in maples mostly in the south growing in sunny places. I've always assumed it was an adaptation to sun, heat and perhaps insects. I dug up a seedling with the corky bark (from the Ouveze valley in the Drome) to plant here but unfortunately it didn't survive the trip. (Can't see the post you've referenced, it wants me to log in.) I haven't noticed a difference in the leaves, but these are pretty variable throughout the species. I have both shaped and unpruned field maples, and I haven't noticed that this makes any difference in the corkiness of the bark. @Michael F there are still many large browsers around here, and maple-fed, more's the pity! :)
