Aster (divaricatus)

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/

---

Family Scientific Name:	Asteraceae
Family Common Name:	Aster Family
Scientific Name:	Aster divaricatus
Common Name:	White wood aster
Species Code:	ASTDIV
Ecotype:	George Washington Memorial Parkway
General Distribution:	New Hampshire, New York and southern Ohio south to Georgia and Alabama. Found in dry to moist woodlands and thickets.
Propagation Goal:	plants
Propagation Method:	seed
ProductType:	Container (plug)
Stock Type:	Container plugs
Time To Grow:	14 Weeks
Target Specifications:	Stock Type: container plugs. Height: 4-6" at outplanting after cutbacks. Caliper: N/A. Root System: Firm full plug; roots fill container.
Propagule Collection:	Collected at roadside of Spout Run by J. Englert on 10/25/95.
Propagule Processing:	Seed Processing: For aster species that are grown in NPMC production fields, seed is harvested with a modified Trac-Vac which removes only the seed with pappus from the stem (seed harvest may be performed with any other vacuuming process such as a shop vac or modified leaf blower). In cleaning, the pappus is removed from the seed by a debearder modified by NPMC staff for small seed lots. For ease of cleaning, large seed lots are first run through a large clipper before being further refined in a desk top clipper. Either machine will need a solid bottom screen and top screen with holes large enough for the seed to fall through. Fan speed is set low enough to blow only empty seed out. Removing the pappus from the seed of aster sp. reduces the cleaned seed weight by approximately 10 times and seeding rates will have to be adjusted to reflect the greater number of seeds per gram (seed with pappus may average 240 plugs per gram, while cleaned seed without pappus may average up to 2,000 plugs per gram). Seeds/Kg: Unknown; seed is extremely small. Germination: Not tested. Purity: Not determined.
Pre-Planting Treatments:	Seed Treatments: Seed germinates in light, therefore it should be surface-sown.
Growing Area Preparation/ Annual Practices for Perennial Crops:	Propagation Environment: Greenhouse with alternating day/night temperatures; daytime temperatures vary from 70-85§F depending on natural solar; night temperatures average around 65-68§F. Plugs were grown under 14-16 hour long day conditions using high pressure sodium lighting from 4:30-10:30 p.m. Seed Propagation Method: If seed had pappus still attached it was surface sown over germination tray cells in small clumps. Cleaned seed without fluff was mixed with talc and surface-sown using a salt shaker. Container Type and Volume: Seed is started in 392 or 406 germination plug trays. See Sowing Technique for further discussion. Seedlings are transplanted into Ropak Multipots (67 cell) or 72 trays. Growing Media: Seed is sown onto germination mix. Seedlings are transplanted into Sunshine #1 (72's) or #5 (multipots). The potting mix is amended with 18-6-8,180-day Nutricote SR (0.15 lb./cu. ft., or 20 oz. per 3.8 cu. ft. bale of potting media).
Establishment Phase:	Sowing Date: Winter, depending on time of planned outplanting in the spring. % Emergence and Date: Using the following protocol, most of the seeds that will germinate have done so within 4 to 7 days. Sowing/Planting Technique: Seed is small and is surface-sown on germination trays. Uniformity of germination is greatly enhanced by keeping seed trays moist and warm. Trays were covered with clear plastic and placed on heat mats set at approximately 75§F. Using this protocol, seedlings emerged in about 3-5 days, with multiple seedlings in each cell, and target number of seedlings germinate within a week. We have hesitated to direct-sow aster seed into final containers because cells germinate irregularly or too thickly and there is often uneven growth and maturation of the seedlings. Selecting plugs from the germination trays that are at the same stage of development provides reasonable assurance that contract goals and deadlines will be met. Since we started using the above protocol, germination occurs much more quickly (in days rather than weeks), more seedlings germinate and seedlings grow more evenly. Establishment Phase: Seedlings in germination trays need to be kept evenly moist. We have put trays under mist, but slowing of growth may occur if left too long. Pulling plugs is easier if there are multiple seedlings in each cell and this can be done early. Seedlings seem to grow more rapidly the sooner they are bumped up to plug trays with larger cells, potting media and fertilizer. Thinning of crowded seedlings may be required to allow one seedling to dominate the cell.
Active Growth Phase:	Rapid Gowth Phase: Transplanted plugs are lightly fertilized approximately bi-weekly, or as needed, with a soluble fertilizer (Technigro 16-17-17 @ about 100 ppm). Cutbacks are performed to keep top growth uniform and strong, to prevent shading of smaller leaves, and to control insect pests and fungus. Foliage does attract typical greenhouse pests (aphids, mites, whiteflies) but cutbacks will eliminate many larval forms. Spot treat with insecticides/miticides as needed.
Hardening Phase:	Hardening Phase: Approximately 2 weeks prior to outplanting, temperatures are reduced in the green house or plants are moved outdoors to a sheltered location, weather permitting, and fertilization is stopped.
Harvesting, Storage and Shipping:	Harvest Date: Seed is harvested in late fall, after some frosts. Plugs are outplanted in the spring. Total Time to Harvest: About 12-14 weeks from germination to finished plug. Storage Conditions: Plugs are grown and planted the same season and have not been over wintered at the NPMC. Seed storage: Seed was stored in paper seed collection bags in NPMC cooler at 40§F and 35% relative humidity. Aster (sp) seed collected in 1994 is still germinating well under these conditions.
Length of Storage:	N/A.
References:	Brown, M. L. and R. G. Brown. 1984. Herbaceous Plants of Maryland. Port City Press, Inc. Gleason, H. A. and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States and Adjacent Canada, 2nd edition. New York Botanical Garden.

Citation:

Kujawski, Jennifer L.; Davis, Kathy M.. 2001. Propagation protocol for production of Container (plug) Aster divaricatus plants Container plugs; USDA NRCS - Norman A. Berg National Plant Materials Center Beltsville, Maryland. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2024/05/18). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.