The tulip tree (Liriodendron tulipifera) grows to a height of 80 to 100 ft. and produces beautiful yellow-green flowers with a touch of orange. However, the Joyce Kilmer Forest in North Carolina has old trees that are higher than 150 ft.; their trunks are seven feet in diameter. The tulip tree grows in USDA zones 5 through 9a and is a North American native tree. It needs full sun to grow well and tolerates clay, loam, sand and acidic soils. The tree is also called tulip poplar, white poplar, yellow poplar and whitewood. Like other plants and trees, Liriodendron tulipifera is susceptible to several diseases.
Cylindrocladium scoparium is a nursery disease that causes root rotting. Lesions appear on the roots and stems of the tulip tree. If your tulip tree exhibits poor growth or lesions, it will probably not survive. The fungus Armillaria mellea attacks and kills tulip trees that are weak because of competition, climate factors or pests. The fungus appears in almost every state. According to the United States Forest Service, it is difficult to detect this fungus because it commonly inhabits the roots. The Collybia velutipes fungus causes limbs to break and die. The only remedy for these diseases is to remove the tree.
Different cankers affect the tulip tree. One of these is the Fusarium solani. This pathogen attacks weakened trees. One of the Myxosporium fungi causes the formation of cankers. Symptoms of these diseases include branches dying back and cankers on the trunk and branches. Another symptom of this fungus is chlorosis, which is the whitening or yellowing of leaves. You can help prevent cankers on tulip trees by pruning infected branches. Verticillium wilt makes leaves wilt and die; a serious infection will cause the whole tree to die. Regular fertilizing will help prevent verticillium wilt; however, you should not use a fertilizer with a high nitrogen content.
Do not water your tulip trees with sprinklers. Water them with an in-ground drip irrigation system or put a hose with a slow drip of water near the base of the tree Watering the trees in these ways helps prevent powdery mildew.
Controlling aphids helps keep black sooty mold from forming. Applying horticultural oils and soaps reduces aphid populations. Using a soil systemic insecticide for aphids is better than spraying the trees, as these insecticides allow beneficial insects to survive. Cut off branches with leaves that have leaf spots. Chemicals will not control this disease.
Planting Tulip Trees
You should plant only healthy, disease-resistant tulip trees. According to the Natural Resources Conservation Service, you should soak the roots in water for one hour to increase the chances of your tree surviving.