Grindelia (hirsutula)
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John W. Hunt Project Manager/Ecologist University of California - Chico California State University, Chico Chico, California 95929-0555 530-228-7594 530-898-4363 (fax) jwhunt@csuchico.edu www.idahobotanicalgarden.org |
| Family Scientific Name: | Asteraceae | ||
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| Family Common Name: | Sunflower | ||
| Scientific Name: | Grindelia hirsutula | ||
| Common Name: | Gumplant; Foothill gumplant | ||
| Ecotype: | Seed collected at The Nature Conservancy's Dye Creek Preserve and Hog's Back Ridge, eastern Tehama County, California | ||
| General Distribution: | California (to British Columbia?). Sandy, clay, or serpentine slopes or roadsides below 1,700 meters (Hickman 1993). | ||
| Propagation Goal: | plants | ||
| Propagation Method: | seed | ||
| ProductType: | Container (plug) | ||
| Stock Type: | Potted nursery stock | ||
| Time To Grow: | 0 | ||
| Target Specifications: | First year rosette with robust taproot. | ||
| Propagule Collection: | Collect whole fruiting heads when fruit is completely ripe from mid-summer to early fall. | ||
| Propagule Processing: | Seed can be collected rapidly in large quantities by collecting whole ripe flower heads from mid-summer to early fall. Seed can be rapidly separated from receptacle by allowing heads to dry and knocking seed from receptacle. Seed can also be rapidly collected off the plant by allowing heads to completely dry on plant, at which time seed will readily fall from receptacle. Bracts within receptacle are difficult to separate from seed. Approximately 150-200 seeds per gram, depending on individual, population, year and cleanliness of seed. An average of 65 seeds per head were observed (low of 35 and high of 90). | ||
| Pre-Planting Treatments: | None, though clean dry seed was placed in dry, cold storage following collection and prior to sowing. | ||
| Growing Area Preparation/ Annual Practices for Perennial Crops: |
During November 2004, seed was directly sown into 1.5" deep flats containing a potting mixture of approximately 1:1:1:2 sand:pumice:peat moss:fir bark mixture. Flats were placed in an outdoor cold frame from late-fall though spring. Most seedlings were transplanted into various sized pots ranging form D-pots to 3x4" plastic containers (some seedlings were not transplanted) using the same potting mixture. Active growth occurs well into summer with summer moisture. Better growth may be obtainined during the first year by avoiding transplanting (seed directly into larger containers rather than flats). Growth from seed to dormant seedling follows the first fall rains through the spring-summer dry-down. | ||
| Establishment Phase: | Initial germination was observed within 1-week; Germination rates of approximately 38% - 84% were observed for seed sown in an outdoor cold frame. Lower germination rates (34%) were observed under controlled conditions for seed cold-stored at approximately 44F in moist vermiculite. Robust seedlings forming a thick (3-6 mm diameter) taproot with fibrous lateral roots and a thick rosette can be grown by late summer the first year (i.e. within 8 months). | ||
| Length of Establishment Phase: | Transplantable sprouts were established within approximately 2-3 weeks. | ||
| Active Growth Phase: | Active growth was observed from the onset of autumn rains (seed swelling) until mid-late summer (the typical flowering period for this ecotype). Above ground growth for mature individuals may not start until mid-winter or early spring. | ||
| Length of Active Growth Phase: | Approximately 8-9 months. | ||
| Hardening Phase: | Hardening is not necessary as the active growth is generally initiated between mid-late fall and continues until early fall, at which time senescenc occurs. Growth resumes following fall rains and possibly not until late winter/early spring (for older plants). | ||
| Harvesting, Storage and Shipping: | If soil is kept moist, individuals can be grown through the summer. | ||
| Other Comments: | Flowering: Early spring - late fall (Oswald and Ahart 2002). Seed collection late spring through late fall (best during late summer-early fall). Seed can be readily knocked from extremely dry receptacles, however, receptacle bracts are very difficult to separate from seed. | ||
| References: | Hickman, James, Ed. 1993. The Jepson Manual: Higher Plants of California. University of California Press, Berkeley, California.; Oswald, Vern and Lowell Ahart. 2002. Selected Plants of Northern California and Adjacent Nevada. CNPS | ||
Citation:
Leigh, Mark; Pushnik, James C.; Boul, Rachelle D.; Brown, Matthew R.; Hunt, John W.; Koenig, David A.. 2006. Propagation protocol for production of Container (plug) Grindelia hirsutula plants Potted nursery stock; University of California - Chico Chico, California. In: Native Plant Network. URL: https://NativePlantNetwork.org (accessed 2024/07/03). US Department of Agriculture, Forest Service, National Center for Reforestation, Nurseries, and Genetic Resources.
