An oak tree planted in Nazi-occupied Poland during World War Two to mark Adolf Hitler's birthday may soon face the axe if the local mayor has her way.

Authorities in Jaslo in rural southeastern Poland discovered the origins of the tree when plans were lodged to fell it to make way for a traffic roundabout.

"We obtained information that this is no ordinary tree but was put here to mark Adolf Hitler's birthday," said Jaslo's mayor, Maria Kurowska. "So should I try to improve our town's communications or should I allow a memorial to that criminal to remain standing? The choice is simple for me."

Nazi Germany invaded Poland on September 1, 1939, triggering World War Two and beginning more than five years of occupation. Six million Poles died, including almost all of the country's three million Jewish citizens.

Not everybody in this town of 38,000 shared Kurowska's view that the tree must go.

"It was 1942 when the Germans brought a seedling of an oak here and planted it in the centre of the town with all honours, an army orchestra and salutes," said Kazimierz Polak, who was present at the planting ceremony as a child 67 years ago.

"My father told me then that it was Hitler's birthday and we found out later the seedling had come from Braunau am Inn (in Austria) where Hitler was born," Polak said.

"It's a historic curiosity. What is the oak really guilty of? It's not the tree's fault that it was planted here to honour the biggest criminal and enemy of Poland."