We all know that when we plant seeds, it can take two years before they germinate. I found these in pots where I planted seedlings last year, or even 2 years ago. They were probably from a batch of mixed seeds, and when the wings of the samaras are gone, somme seeds are very small and can look like grains of sand. And it's hard to keep a record of everything you plant. The first one a sort of red dissectum, the second one (and the third one) at the foot of what I think is Acer oliverianum. :