Maple and Scarlet maple

Maple noun - Any of numerous trees or shrubs of the genus Acer bearing winged seeds in pairs; north temperate zone.

Scarlet maple and maple are semantically related. In some cases you can replace phrase "Scarlet maple" with "Maple", this terms are similar.

Scarlet maple noun - Maple of eastern and central America; five-lobed leaves turn scarlet and yellow in autumn.

Maple and scarlet maple are semantically related. You can use "Maple" instead a noun phrase "Scarlet maple".