I had heard about the champion wingnut tree in Bute Park, Cardiff, months before I first located it. I have been visiting the park – and the Paulownia tree I am following – since January, but I didn’t spot the wingnut tree until March. Despite the fact that it is considered to be a bit of a landmark, next to the red footbridge over the River Taff.
Here are my pictures from March to May, a “mini follow”, as I doubt if I will look at it again until autumn, as most trees become a bit unappetising in full summer (controversial!)
I thought it was a Caucasian wingnut (Pterocarya fraxinifolia), but a quick check on the council website tells me it is a Pterocarya × rehderiana, a hybrid wingnut first grown at the Arnold Arboretum in Boston in 1879 by Alfred Rehder, hence the name. It is a cross between the Caucasian wingnut and Chinese wingnut (Pterocarya stenoptera).
The wingnut genus Pterocarya (which literally means “wing-nut” in Greek) is part of the walnut family, Juglandaceae. The word Juglans means walnut in Latin and that’s a contraction of Jovis glans, meaning “nut of (the god) Jupiter”.
A look at details
The wingnut tree is monoecious, with male and female flowers on the same tree. The male catkins are shorter and fatter than the female ones, which are long and dangly and sparser in appearance. Are those pictured above male? Or just not grown yet?
This tree has a bit of a feel of the hornbeam (Carpinus betulus) I followed last year. I think it’s the splayed shape and the particular shades of green of the developing leaves, and of course both trees have catkins. The two species are VERY distantly related, as the family Juglandaceae, the walnuts, and the family Betulaceae, the birch family, which includes hornbeam, are both in the higher order Fagales, named after another member of the order, the beech (Fagus). I can see they are all vaguely similar. Do they ALL have catkins? And do any trees have catkins that aren’t in the order Fagales?
Growing under the tree
I’ll probably look away now, until the leaves change colour or the fruits start to form. I’m expecting the nuts to have wings…