There were already a few Christmas trees at the curb in Olean on Monday. But were the trees put out because residents see the Christmas season as over or because the trees were beginning to copiously shed needles on the floor? Well, Christmas trees that hold their needles for weeks longer may be among the results of a globe-trotting, multi-university research project. Searching for trees that can fend off diseases threatening the most popular Christmas tree varieties â noble and Fraser firs â the 10-year Collaborative Fir Germplasm Evaluation Project eventually focused on fir trees from ... Turkey. Outdoors and nature writer Marcus Schneck of pennlive.com reports that seeds from fir trees in the Eurasian countries have been planted and grown out at tree farms by universities across the country, including Penn State.