Yes, I showed you the difference between a male flower and female flower on the birch @Barski
Thanks for the well-worded and helpful comment @Barski
I must add that in birch, there is only one kind of tree that has both male and female catkins on the same tree. What I was trying to show was that both male and female flowers are on the same tree.
This is unlike the case of Goat willow (Salix caprea) where some trees only have female flowers and other trees that just have male flowers.
See link: https://steemit.com/spring/@siggjo/male-and-female-catkins-bloom-on-goat-willow
On the birch, all trees have both male and female flowers.
Hope this clarifies the difference between the Goat willow tree and birch.