a mulberry sapling growing from the concrete soils of torontos landfill park. which mulberry of the many species this is i have not researched. it could be the native north american, that asian, or the increasingly common hybrid of the two, they are hardier than a lot of mulberries and so a good bet it's one of them.
self sown or planted by the cities parks and recreation department i ve no idea. there was no stake or stem shield and while they might plant the native species it's not likely they would plant the asian type in this park which they go to some trouble eradicating exotic plants. so my guess its a self sown plant of one of the three mentioned above, though there are no other mature and fruiting mulberry trees that i've seen in this park. perhaps a bird planted it after a meal of fruit from a tree further inland.