Angle isn't the best for ID, but it may be a mulberry

probably mulberry.. deposited by a bird sitting on your gutter.. suffering wildly from eating too many Ms... lol

ken

Thank you both! Although I wouldn't be opposed to having a Mulberry somewhere in my yard, a foot from the house (almost blocking the gate) is not ideal. Would it transplant well?

Yes, it can be transplanted... late autumn or early spring.