The most cold hardy citrus tree is the kumquat, closely followed in second place by mandarin orange, the orange that is famously used in Chinese cooking known as Mandarin Chinese food. The Mandarin orange is self pollinated and Mandarin Orange trees grafted onto trifoliate rootstock that tends to make it more cold hardy by dwarfing the tree and slowing down the rate of growth that is so easily damaged by freezes. The characteristics of cold hardiness and loose skin peeling also increase the popularity of Mandarin orange and the bright colored skin and pulp are important in helping to increase customer instinct buying and customer appeal. When peeled and chilled Mandarin orange is pleasantly fragrant with a distinct Mandarin citrus aroma and the flavor has been revered in the Orient for centuries in food preparation and for fresh eating and delicious orange juice.