Do you unwrap presents beneath a fir tree every Christmas? If so, you should enjoy it while you can, as they might not be around much longer in Minnesota.

If the warming of the earth's climate continues as it has been, Christmas tree species such as the fir and spruce will be pushed out of Minnesota's northern forests in future decades, according to a study by the University of Minnesota.

In their place will be maples and oaks, which the study found would thrive in a warmer climate as researchers tested northern forest species by using ceramic heaters to warm the air near to seedlings.

This past Christmas, an 88-foot white spruce was chosen as the U.S. Capitol Christmas tree, but in future years they would have to send pines, as these are the only festive species that could withstand a temperature increase of just a few degrees.

The study says spruce and fir found it more difficult to survive when the temperature was warmed, declining in growth by up to 40 percent, the Pioneer Press reports.

"The change in the forest will influence everything from the supply of timber to habitat for wildlife to its allure for recreational use and tourism," Peter Reich, of the university's forest resources department, told Science Daily.

The Minnesota Department of Agriculture says Christmas tree farmers market around 500,000 trees in the state every year, with the balsam fir and fraser fir the most common varieties, ahead of Scotch pine.

Spruces are also common, with the blue spruce, Colorado spruce and white spruce among the varieties grown in the state.