In this task, you're given a passage, further information available on a particular linked term from the statement, and a question. Your job is to generate the answer to the question by using the information provided. If there is no clear answer obtainable, output 'none'.

Passage: In the United States it is the State Tree of Maine (as of 1945) and Michigan (as of 1955). Its "pine cone and tassel" is also the State Flower of Maine. Sprigs of eastern white pine were worn as badges as a symbol of Vermont identity during the Vermont Republic and are depicted in a stained glass window in the Vermont State House, on the Flag of Vermont, and on the naval ensign of the Commonwealth of Massachusetts and the state of Maine. The 1901 Maine Flag prominently featured the tree during its brief tenure as Maine's state flag. The Maine State Guard also use the tree in their uniform badges.
Link Information: Flag of Maine (190109)
Question: How many years was the Pinus strobus seen on the state flag of Maine?
Answer: 8