The term “Soft Maple” does not refer to any specific species of maple its used to differentiate these species from Hard Maple.

Hard Maple, refers to one specific type of maple species the  Rock Maple or Sugar Maple, (this is the same tree which is tapped to get maple syrup). The only other species that is sometimes considered in the grouping of Hard Maple in the United States is Black Maple. Black Maple is so closely related to Hard Maple that some even consider it to be a sub-species of the same tree.

Some of the most common species of maple that fall under the grouping of Soft Maple are:
•Bigleaf Maple •Box Elder •Red Maple •Silver Maple
•Striped Maple)