Robinia (pseudoacacia)

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:	Fabaceae
Family Common Name:	Bean Family
Scientific Name:	Robinia pseudoacacia L.
Common Name:	black locust
Species Code:	ROBPSE
Ecotype:	Cumberland Gap National Historical Park, Shenandoah National Park
General Distribution:	R. pseudoacacia is native from Pennsylvania and south Indiana to Oklahoma, south to Georgia and Alabama.Escaped from cultivation north to Nova Scotia and Quebec. (Gleason and Cronquist, 1991). Note: Black locust is on the native species list for the above national Parks. NRCS recognizes that it can be weedy outside its native range. Please consult the NRCS PLANTS database for more information.
Propagation Goal:	plants
Propagation Method:	seed
ProductType:	Bareroot (field grown)
Stock Type:	Seedling
Time To Grow:	1 Years
Target Specifications:	Root systems: Bareroot seedlings should have well-developed root systems. Long roots are pruned as needed at harvest.<br> Height: 1+0 bareroot seedlings vary from 8-48 inches.
Propagule Collection:	Seed was collected from the Parks in September and October after it had ripened but before the legumes had split.
Propagule Processing:	Cleaning: Seeds are spread out to dry. Dried pods are run through a hammermill to separate out the seed from the chaff. Storage:Cleaned seed is stored in sealed containers in a cooler at 40F and 30% relative humidity. Purity:After cleaning, purity was estimated at over 98%. Germination: untested. Recently, harvest has been between 1% and 2% of all seeds planted. Germination depends on quality of seed and seed lot and if there has been insect damage. It varies by park. Seeds per Kg: between 55,600 and 89,300 (66,700 average).
Pre-Planting Treatments:	Black locust seeds have an impermeable seedcoat (Olson, 1974). Prior to planting, seeds were run through a Fosburg scarifier to scratch the seedcoat and then were inoculated with rhizobia specified for Robinia.
Growing Area Preparation/ Annual Practices for Perennial Crops:	Propagation environment: Bareroot seedlings are grown in outdoor woody nursery beds. Sowing date: Seeds has been sown in outdoor nursery beds in November, December, January, and April with no appreciable difference in production. Sowing/planting technique: Woody nursery: Pre-scarified and inoculated seeds are dusted with fungicide and hand-sown into rows. Rows are 5-6 inches apart and seeds are sown about 1" apart within each row. Endomycorrhizae are sprinkled over the seed before covering with about _" of soil. The beds are then mulched with aged sawdust, which is scraped back in the spring before seedling emergence.
Establishment Phase:	Seedlings emerge during the spring following fall sowing, or shortly after spring sowing. Newly emerged seedlings are monitored closely for irrigation needs. Seedlings are not shaded.
Active Growth Phase:	Outdoor woody beds: The NPMC soil is a nutrient-poor sandy loam which is amended with organic matter, such as composted leaves and manure. Seedlings in the nursery beds are fertilized every other week from early May 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 fertilizer application. The rate of water applied is determined by soil moisture prior to irrigation.
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.
Harvesting, Storage and Shipping:	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. Prior to shipment, roots of the bundles are dipped in a mycorrhizal slurry and sealed in air-tight plastic. This has prevented desiccation of roots in transport and outplanting.
Length of Storage:	4 months
Other Comments:	This species has also been propagated by root cuttings from seedlings in the outdoor nursery beds. Clones produced from root cuttings have not been as high quality as plants from seed. Cuttings also produced large multi-stemmed plants in one season that are difficult to harvest mechanically.
References:	References: Olson, David F. 1974. Robinia In: Seeds of Woody Plants in the United States. Forest Service, USDA. Agricultural Handbook 450. Washington, DC. 728-731. 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. 2003. Propagation protocol for production of Bareroot (field grown) Robinia pseudoacacia L. plants Seedling; USDA NRCS - Norman A. Berg National Plant Materials Center Beltsville, Maryland. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2024/07/22). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.