Liquidambar (styraciflua)

John M. Englert USDA NRCS - Norman A. Berg National Plant Materials Center Bldg. 509, BARC - East, E. Beaver Dam Road Beltsville, Maryland 20705 (301) 504-8175 (301) 504-8741 (fax) john.englert@wdc.usda.gov http://plant-materials.nrcs.usda.gov/mdpmc/

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Family Scientific Name:	Hamamelidaceae
Family Common Name:	witch-hazel family
Scientific Name:	Liquidambar styraciflua L.
Common Name:	sweetgum
Species Code:	LIQSTY
Ecotype:	Cumberland Gap National Historical Park, Great Smoky Mountains National Park.
General Distribution:	General Distribution: Moist or wet woods; Connecticut to southern Ohio, southern Illinois and Oklahoma, south to Florida and Guatemala. (Gleason and Cronquist, 1991)
Propagation Goal:	plants
Propagation Method:	seed
ProductType:	Bareroot (field grown)
Stock Type:	bareroot seedlings and specimen plants in 2 or 3-gallon containers
Time To Grow:	0
Target Specifications:	Time to Grow: Seedlings are harvested after growing for two years in outdoor nursery beds. Most go out bareroot to the park in early spring following harvest. Some bareroot seedlings are retained as specimens. These are potted up into 1-gallon containers in late spring and moved to a shade house where they are grown to 2 or 3-gallon size as specified by the park for an additional 2-4 years.<br><br> Root Systems: Bareroot: well-developed, fleshy root system. Long roots are pruned as needed at harvest.<br>Container: Firm root ball that fills a container treated with Spin Out, a copper hydroxide product that inhibits root girdling.<br> Height: 2-0 bareroot seedlings are 12-40 inches. 2-2 plants in 3-gallon containers are up to 48".
Propagule Collection:	Mature fruit heads were collected early October in the Great Smoky Mountains and between Oct. 11 and Nov. 5 in Cumberland Gap. Yellowing color indicates maturity.
Propagule Processing:	Cleaning: Cloth bags containing mature fruit heads are spread out on greenhouse benches to dry for 5 to 10 days. The bags are then shaken to dislodge seeds. Debris is then removed by screening. Storage: if seeds are not sown the season of collection, they are stored in seed collection bags in a seed cooler at 40F, 35% relative humidity. Germination/purity: Purity is estimated at 97% after cleaning; between 7% to 22% of seeds sown reached harvest size, depending on park, year and seed lot. Seeds per kg: between 167,000-196,000. (179,000 average)
Pre-Planting Treatments:	Seeds exhibit shallow dormancy but germination is improved by cold, moist stratification. (Bonner, 1974) Seeds are sown outdoors in NPMC woody nursery beds from mid-November to mid-December to allow natural stratification to occur.
Growing Area Preparation/ Annual Practices for Perennial Crops:	Propagation environment: bareroot seedlings are grown in outdoor woody nursery beds; container specimens aregrown to finished size in a container nursery. Sowing date: mid-November to mid-December. Sowing/planting technique: Seeds are dusted with fungicide and hand-sown into rows. (Rows are 5-6 inches apart and seeds are sown close together within each row). Endomycorrhizae are sprinkled over the seed and the row is covered with about _ inch of soil. The beds are then mulched with aged sawdust, which is scraped back in the spring before seedling emergence.
Establishment Phase:	Seedlings generally emerge during the spring following fall sowing. Newly emerged seedlings are monitored closely for irrigation needs.
Active Growth Phase:	Outdoor woody beds: Because NPMC soil is a nutrient poor, sandy loam, seedlings in the outdoor nursery beds are fertilized once weekly from mid-April through early June with a granular 10-10-10. From mid-June through late July, the 10-10-10 is alternated with a granular urea. Fertilization from late July through late August is bi-weekly with 10-10-10. Overhead irrigation is used after each fertilization. The rate of water applied is determined by soil moisture prior to irrigation. Container nursery: Containerized specimens are grown in a container nursery during the growing season until reaching outplanting size at 2 or 3 gallons. Plants are bumped up to the next container size in successive springs using a customized woody mix (3.8 cu. ft. bale Sunshine #1, 4 cu. ft. pine bark mulch, 4 cups 180 day controlled release Nutricote 18-6-8 with micros and about 4 cups of endomycorrhizae per batch). Plant roots usually need a season or more after each bump-up for roots to fill the containers. Daily irrigation is adjusted depending on natural precipitation and pot size. 2 and 3-gallon containers are moved to drip irrigation in full sun. If additional nutrients are needed, containers may be top-dressed with controlled release Nutricote at manufacturer-recommended rates. If a central leader dies back, suckering will occur from the base. Prune as needed while dormant to a central leader and to shape the plant.
Hardening Phase:	Outdoor woody nursery beds: During mid- to late summer, fertilization is cut back to twice monthly. Beginning in September, irrigation is only used in a severe droughty situation. <br>Container nursery: frequency and duration of irrigation is reduced as plants go dormant, depending on natural rainfall.
Harvesting, Storage and Shipping:	Bareroot: Dormant bareroot plants are harvested in early to mid-December. A bareroot seedling harvester is used to lift plants in the woody bed. Seedlings are then hand-sorted by size and tied in manageable bundles. Roots are pruned as needed and kept moist until packing. Bundles are packed in plastic bins with drainage holes and roots are covered with moist sawdust. Bins are held in cold storage at 40F and watered as needed. Containers: dormant containerized stock is overwintered outdoors under a microfoam-insulating blanket. After leaves have fallen, the clean, well-watered containers are overlapped on their sides on weed barrier fabric and covered with microfoam. Rodenticide baits are placed at intervals under the blanket to discourage gnawing rodents. The microfoam is then secured.
Length of Storage:	3-5 months
References:	Bonner, F. T. 1974. Hamamelis In: Seeds of Woody Plants in the United States. Forest Service, USDA. Agricultural Handbook 450. Washington, DC. 505-507. Brown, Russell G. and Melvin L. Brown. 1992. Woody Plants of Maryland. Port City Press, Baltimore, MD> Dirr, Michael A. and Charles W. Heuser, Jr. 1987. The Reference Manual of Woody Plant Propagation. Varsity Press, Inc., Athens GA. Gleason, Henry A. and Arthur Cronquist. 1991. Manual of Vascular Plants of Northeastern United States and Adjacent Canada. 2nd. Edition. New York Botanical Garden, Bronx, NY. USDA-NRCS National Plant Materials Center. Woody bed and container nursery plant records. Unpublished.

Citation:

Davis, Kathy; King, Brandy; Kujawski, Jennifer. 2002. Propagation protocol for production of Bareroot (field grown) Liquidambar styraciflua L. plants bareroot seedlings and specimen plants in 2 or 3-gallon containers; USDA NRCS - Norman A. Berg National Plant Materials Center Beltsville, Maryland. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2024/07/02). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.