2-gal refers to the size of the container (2 gallon)in which the plant is sold in. 6'-7' is the height of the plant when purchased.

Many states no longer allow the plant containers to be labelled as "gallons" because of the fact that they regulate things sold by the gallon through a bureau of weights and measures and the containers are seldom exactly a those sizes. It is increasingly common to find these now listed as "#2" rather than 2-gal.. Your government at work.

The sizes of the plants being described should meet the American Nurseryman's Association standards, not just any plant that they pop into a big can.

Any nursery is going to know exactly what you are talking about when you ask for these plants.

Thank you.