Notholithocarpus (densiflorus)

Lee Riley Horticulturist USDA FS - Dorena Genetic Resource Center 34963 Shoreview Road Cottage Grove, Oregon 97424 541-915-7324 541-767-5709 (fax) lee.riley@usda.gov

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Family Scientific Name:	Fagaceae
Family Common Name:	Beech
Scientific Name:	Notholithocarpus densiflorus
Common Name:	tanoak
Species Code:	NODE3
Ecotype:	Various sites in southern Oregon
General Distribution:	Tanoak occurs on fertile mountain slopes and ridges below 1200 meters in the Coast Ranges from the Santa Inez Mountains in Southern California, to the Cascade Ranges in Southwestern Oregon
Propagation Goal:	Plants
Propagation Method:	Seed
ProductType:	Container (plug)
Stock Type:	656 ml (40 in3) container
Time To Grow:	22 weeks
Target Specifications:	Stock Type: Container seedling Root System: Firm plug in container.
Propagule Processing:	Tanoak nuts do not store. Fresh seeds can be surface dried, placed in plastic bags, and stored at 3 °C for up to 3 to 4 weeks. The nuts should not be allowed to dry completely. Nuts should be placed in stratification within 1 month following collection. Empty and damaged nuts will float and are easily removed during soaking prior to stratification.
Pre-Planting Treatments:	If tanoak nuts have been collected from areas infested with Phytophthora ramorum, or within quarantine areas, the best precaution is to soak nuts in a 1% bleach solution for 10 minutes to surface sterilize the nuts. There is no evidence to date that P. ramorum has been found inside the seed coat. Following the bleach soak, nuts are placed into a 1% hydrogen peroxide (3:1 water/3% hydrogen peroxide) soak for 24 hours, rinsed, and placed in aerated water for an additional 48 hours. The nuts are then placed in mesh bags, layered in peat and sealed in containers that are placed in refrigeration at 1 to 3 °C for 45 days. It is very important to check seeds weekly. If mold is evident, seeds should be treated with 1% hydrogen peroxide. Germination may begin to occur during the stratification period in collections from some locations. If radicles have started to emerge, the germinated seeds should be sown immediately.
Growing Area Preparation/ Annual Practices for Perennial Crops:	Seeds are directly sown into containers from stratification trays. Seeds are lightly covered with nursery grit. Growing medium used is 40:20:20:20 peat:composted fir bark:perlite:pumice with Apex controlled release fertilizer (16N:5P2O5:10K2O with minors; 6 to 7 month release rate at 21C) at the rate of 3 g Apex per 656 ml container.
Establishment Phase:	Germination and emergence can be somewhat uneven, depending on collection location, and may take up to 4 weeks to be complete. Once the majority of germination has occurred, cells are fertilized for 3 weeks with soluble 12-2-14-6Ca-3Mg at 75 to 100 ppm.
Length of Establishment Phase:	5 to 6 weeks
Active Growth Phase:	Following emergence, tanoak grows rapidly. During the growing season, fertilization depends on weather and physiological needs. Soluble 20-9-20 NPK, 20-18-18 NPK, or 17-5-24 NPK at a range of 100 to 150 ppm is applied weekly. It is easy to overwater this species, so irrigation must be carefully controlled.
Length of Active Growth Phase:	18 to 20 weeks
Hardening Phase:	Irrigation is reduced starting in early September. Seedlings are moved to an outdoor growing area in mid-September induce dormancy.
Length of Hardening Phase:	3 to 4 weeks
Harvesting, Storage and Shipping:	Harvest Date: Mid-October Storage Conditions: Seedlings are usually outplanted in fall. No storage except in outdoor growing area. Plants are well irrigated prior to shipping and shipped in containers.
Other Comments:	Use only fresh seeds, as the seeds do not retain viability Tanoaks may be used for erosion control on sites that experience frequent disturbance Acorns ripen in the fall of the second season The majority of tanoak at Dorena Genetic Resource Center has been produced for off-site testing for resistance to Phytophthora ramorum, although seedlings have been outplanted on various sites for validation testing.
References:	Dorena Genetic Resource Center Propagation Records, unpublished. USDA Natural Resources Conservation Service. Notholithocarpus densiflorus (Hook. & Arn.) P.S. Manos, C.H. Cannon, & S.H. Oh tanoak. URL: https://plants.usda.gov/core/profile?symbol=NODE3 (accessed 11 Oct 2018). Immel D. 2002. Plant guide: Tanoak Lithocarpus densiflorus (Hook. & Arn.) Rehd. Davis (CA): USDA Natural Resources Conservation Service Plant Data Center. URL: https://plants.usda.gov/plantguide/pdf/cs_lide3.pdf (accessed 11 Oct 2018).

Citation:

Riley, Lee E.; Klocke, Allison. 2018. Propagation protocol for production of Container (plug) Notholithocarpus densiflorus Plants 656 ml (40 in3) container; USDA FS - Dorena Genetic Resource Center Cottage Grove, Oregon. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2025/02/25). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.