Acer saccharum is called a sugar maple and is native to many parts of northern United States and Canada. Sugar maple is known for being the primary source of maple syrup. It may also be known as "rock maple", "sweet maple", particularly when referring to the wood. The sap contains a large amount of sugar. It can be drunk as a refreshing drink and can also be concentrated in syrup. Tea made from inner skin is used as a blood tonic and diuretic, and it has been used to treat coughs and diarrhea. Sap helps treat eye pain, and inner skin is used as a cough remedy. A study has shown that sap of sugar maple trees have anti-oxidant and anti-inflammatory effects.