Water tupelo (Nyssa aquatica), also called cottongum, sourgum, swamp tupelo, tupelo-gum, and water-gum, is a large, long-lived tree that grows in southern swamps and flood plains where its root system is periodically under water. It has a swollen base that tapers to a long, clear bole and often occurs in pure stands. A good mature tree will produce commercial timber used for furniture and crates. Many kinds of wildlife eat the fruits and it is a favored honey tree.
Water tupelo grows in low, wet flats or sloughs and in deep swamps. Some of the better sites are in the sloughs and swamps along Coastal Plain rivers of the Southeast, such as the Roanoke and Santee, and in the large swamps of southwestern Louisiana and southeastern Texas. On some sites water may reach a depth of 20 ft during rainy seasons and may remain as high as 13 ft for long periods. Surface water may disappear from water tupelo areas in midsummer or fall, but on better sites soil moisture remains at or near saturation level throughout most of the growing season.
Hardy Zone 5-9
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Sowing instructions
Germination is epigeal. Seeds do not germinate until water recedes, which may be midway to late in the growing season. Partially shaded, wet, poorly-drained soils provide the best seedbed. Seeds buried 0.5 to 1 in deep in the soil have a better chance to germinate and establish seedlings than seeds on the soil surface. Seedling survival and development are best in full sunlight and in soil with a pH below 7.0. Seedling development is better in saturated than in well-drained soil, in moving and aerated rather than stagnant water, and in shallow rather than deep water. Provided their tops are above water, seedlings can generally survive continuous flooding even if it persists throughout the growing season. Water tupelo is able to survive where it is too wet for most other species because of anatomical and physiological adaptations such as roots that allow for oxidation of the rhizosphere and controlled anaerobic respiration