Liriodendron tulipifera L.
Other common names include: Tulip poplar, White-Poplar
Native Range - As stated by Donald E. Beck in the Silvics of North America, "The yellow-poplar grows throughout the Eastern United States from southern New England, west through southern Ontario and Michigan, south to Louisiana, then east to north-central Florida."
Climate - The Yellow-poplar grows in a wide variety of climatic conditions. Winter temperatures range from 19 to 61 degrees F. Summer temperatures range from 69 to 81 degrees F. Rainfall averaged 30 to 80 inches, and the average number of frost free days range from 150 to 310 (Beck, 1990).
Soils - The Yellow-poplar is most common in the Inceptisol and Ultisol soils, but grows on a wide variety of soil types. It appears that the only limiting factor is very wet or very dry soils. Although it will grow on those sites, it does poorly. "The best growth usually occurs on north and east aspects, on lower slopes, in sheltered coves, and on gentle, concave slopes." (Beck, 1990).
Reproduction and Growth:
Flowering and Fruiting - "The flower is a singly occurring, perfect flower 4 to 5 cm wide with sex petals varying in color form a light yellowish green at the margin to a deep orange band at the center (Beck, 1990 )." Under normal conditions, the Yellow-poplar begins to flower at age 15 and continues to produce flowers for 200 years (Beck, 1990 and Wilcox, 1990). Grafts can produce flowers in the first two or three years (Wilcox, 1969). The flowers open in early spring, depending on the location and weather conditions this can be from April to June (Beck, 1990), after leaf production. The flowers are receptive for 12 to 24 daylight hours (Beck, 1990 and Wilcox, 1990). Flowers of the Yellow-poplar are pollinated by insects, the most common pollinators are flies, beetles and honeybees (Wilcox, 1969).
Seed Production and Dissemination - "The conelike aggregate of many winged carpels ripens and matures from early August in the North to late October in the South (Beck, 1990)." Seed fall occurs during climatic conditions of high temperatures and low rainfalls (Wilcox, 1969). Underneath a good seed tree it is not uncommon to find 300,000 to 500,000 seeds per acre (Wilcox, 1969). Although the seeds average 5% viability they remain viable in the litter layer for several years. Seeds can successfully be stored in a cooler just above freezing (Wilcox, 1969).
Rotation Length - The Yellow-poplar tree can reach pole size in 20-30 years. Yellow-poplar stands do not require intermediate stand management such as thinnings, but intermediate and overtopped trees respond to release with increased diameter and height growth. Thinnings are usually done to prevent mortality, this increases the growth of residual trees, shortens rotations and increases the yield of high value timber products (Beck, 1990).
Provenances - Results vary in studies that have been performed on provenances. One study shows that the southern sources of seeds produced significantly taller trees than northern sources, and the southern sources leafed out earlier. Another study showed that there were no significant differences in height from one provenance to the other (Wilcox, 1969). In a study from Beck's paper in the Silvics of North America, day length treatments affected Northern and Southern seedlings differently, the Northern source was inhibited by 18 hour day length while the Southern source was not. Not enough information has been gathered about Yellow-poplar provenances to come to a conclusion at this time.
Commercial hybrids - No information was found on commercial hybrids of Yellow-poplar.
Tree Improvement - Cross-pollinated seedlings are found to be more vigorous than open-pollinated seedlings (Beck, 1990).
Propagation Methods - From a clonal seed orchard, grow one year in the orchard and release as a 1-0 planting stock. Eliminate smaller seedlings and maintain uniformity in the nursery beds (Wilcox, 1969).
Pests - A root rot that causes stem and root lesions is Cylindrocladuim scoparium. This often lethal rot causes low survival and poor growth of outplanted seedlings (Beck, 1990).
Seedling Costs - According to Superior Nurseries in Lee, FL, bare root seedlings cost $200/thousand. International Forest Seed Company sells containerized seedlings for $500/thousand in orders of 10,000 or less and $350/thousand for orders of more than 10,000.
Site Preparation - A disturbance of the site that exposes mineral soil is needed for a good seed bed. Regular harvest techniques done in the fall, winter or spring and prescribed fires provide a good area for seed germination. If there is a deep accumulation of litter disking and burning may be effective to prepare the site (Beck, 1990).
Planting techniques - Yellow-poplar is primarily regenerated by the coppice method. Direct seeding is also a good method for regeneration of Yellow-poplar.
Insects and Disease - There are only four insects that attack the Yellow-poplar. The tuliptree scale attacks leaders and saplings which slows growth, the yellow-poplar weevil attacks the buds and foliage, the root-collar borer attacks the base of the tree, feeding on the phloem tissue, providing entry of rots and pathogens, and the Columbian timber beetle stains the wood black which degrades it. Seedlings and saplings are susceptible to damage by fire if their bark is too thin (Beck, 1990)
Weed Control - There is no herbicide available for Yellow-poplar. Mechanical weed control in the form of disking is preferred.
Establishment Costs - Costs of establishing a Yellow-poplar stand varies from location to location. There would be no cost associated with regenerating a clearcut site of Yellow-poplar. Regenerating an old field would require the costs of subsoiling, seeding or seedlings, planting costs and mechanical herbaceous weed control.
Wood Properties and Uses:
Specific gravity - Green Yellow-poplar has a specific gravity of .40, while dry Yellow-poplar has a .42 specific gravity.
MOE, MOR - The Modulus of Elasticity is 6000 and 10,100 pounds per square inch for green and dry wood respectively. The Modulus of Rupture is 1.22 and 1.58 Million Psi respectively (Haygreen, 1989).
Common uses - Yellow-poplar wood is commonly used for furniture and framing construction. The tree itself is used as shade trees and honey trees, and the fruits are good for wildlife food.
Beck, D.E. 1990. "Liriodendron tulipifera." in Silvics of North America Vol 2 Hardwoods. Edited by Burns, R.M. and Honkala, B.H. USDA Forest Service Agriculture Handbook 654. pp 405-415.
Haygreen,J.G. and Bowyer J.L. 1989. Forest Products and Wood Science: An Introduction 2nd Ed. pg. 478. Table A5.
Wilcox, J.R., and Taft, K.A.Jr. 1969. Genetics of Yellow-poplar (Liriodendron). USDA Forest Serv. Res. Pap. WO-6, 12p.
Yellow poplar in Virginia
Yellow poplar in in Oregon
Yellow poplar info from US Forest Service