Lithospermum (ruderale)

Ann DeBolt and Hilary Parkinson USDA FS - Rocky Mountain Research Station 316 E. Myrtle Boise, Idaho 83702 208-373-4366 208-373-4391 (fax) adebolt@fs.fed.us www.fs.fed.us/rm/boise

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Family Scientific Name:	Boraginaceae
Scientific Name:	Lithospermum ruderale Dougl. ex Lehm
Common Name:	Western gromwell, western stoneseed, puccoon
Ecotype:	basin big sagebrush-bluebunch wheatgrass habitat, 945 m, Ada County, ID
General Distribution:	Chiefly east of the Cascade Mountains in open, fairly dry places at mid elevations in the mountains; occurs in all western states except Arizona and New Mexico.
Propagation Goal:	plants
Propagation Method:	seed
ProductType:	Container (plug)
Time To Grow:	0
Propagule Collection:	The pale yellow flowers appear from March to May, depending on elevation, aspect and seasonal weather patterns. The fruit (a nutlet) ripens uniformly in approximately 8 to 12 weeks. The fruit is mature when the nutlets are hardened and dehisce readily, though they persist on the plant for severalweeks. Fruits are hand-stripped from the inflorescence (terminal cyme) into containers. Gloves are recommended due to bristly hairs on the inflorescence. After collecting, the seed was thoroughly dried and placed in a standard freezer for 48 hours to remove insect pests.
Propagule Processing:	Fruits are crushed on a rubbing board, screened through a 12.7 mm square screen followed by a 1.18 mm sieve (No. 16 USA STS). Fine debris is removed by passing the remaining material through a seed blower. Seed was then stored in a brown glass jar at room temperature for 18 months prior to propagation trials.
Pre-Planting Treatments:	Seeds were soaked in water for 24 hours, and then placed in clear plastic germination boxes with two sheets of moistened blotter paper. Boxes were placed in a germinator at 4§C in the dark. After 28 days, mold began developing on the seed. At this time, the persistent receptacle was removed from the seeds, falling off easily or with minimal pressure. The seeds were then washed with tap water and treated with Thiram, an anti-fungal seed protectant. Germination began within 24 hours after receptacle removal. Twenty-eight percent of the washed seeds germinated compared to 32% of the seeds treated with Thiram following washings. Viability of the seedlot was not determined. Receptacle removal may be key to inducing germination but can only be accomplished following imbibition.
Growing Area Preparation/ Annual Practices for Perennial Crops:	Germinants were sown 1 cm deep in styrofoam conetainers filled with a 50% peat and 50% vermiculite mixture. Containers were watered from an automatic overhead irrigation system that turns on when soil saturation levels fall below 80% and turns off when soil reaches 100% field capacity. Greenhouse temperature was set at a constant 27§C. Small amounts of fertilizer suitable for seedlings were added periodically.
Establishment Phase:	About 43% of the seeds germinated. Seeds began showing signs of germinating (hardened seed coat splits apically for the stout hairless radicle to emerge) after 35 days in cold moist stratification. Once germination began, it continued for 60 days, with the majority occurring within the first 22 days. True leaves began developing after approximately 2 weeks in the greenhouse. After 28 days in the greenhouse, the largest seedling was 2 inches tall, with three sets of leaves. Seedling survival in the greenhouse was 70%. About 12% of the seedlings were lost due to damping off, usually before the cotyledons were free from the seed capsule. The leaves of about 20% of the plants began to show some signs of yellowing or chlorosis after developing the third or fourth set of leaves, but no mortality resulted from this condition.
Active Growth Phase:	After approximately 2.5 months in the greenhouse, 39 seedlings were transplanted to a Boise, ID planting site in mid-April. The site is 670 m on sandy sil and receives annual precipitation of 300 mm. Plants were hand watered at 2-3 day intervals. About one-third of the seedlings may have died during the first summer, although some may have merely entered dormancy. Earlier transplanting may permit better development of the taproot during the first year. Survival will best be determined in the spring of 2006.
Other Comments:	Partial funding for this research was provided by the USDI Bureau of Land Management, Great Basin Restoration Initiative. The use of trade or firm names in this publication is for reader information and does not imply endorsement by the U.S. Department of Agriculture of any product or service. This publication reports research involving pesticides. It does not contain recommendations for their use, nor does it imply the uses discussed here have been registered. All uses of pesticides must be registered by appropriate State and/or Federal agencies before they can be recommended. CAUTION: Pesticides can be injurious to humans, domestic animals, desirable plants, and fish or other wildlife-if they are not handled or applied properly. Use all pesticides selectively and carefully. Follow recommended practices for the disposal of surplus pesticides and pesticide containers.
References:	Hitchcock, C. Leo, and Arthur Cronquist. 1973. Flora of the Pacific Northwest. University of Washington Press, Seattle, WA. 730 p. USDA, NRCS. 2004. The PLANTS Database, Version 3.5 (http://plants.usda.gov). National Plant Data Center, Baton Rouge, LA 70874-4490 USA.

Citation:

Parkinson, Hilary; DeBolt, Ann. 2005. Propagation protocol for production of Container (plug) Lithospermum ruderale Dougl. ex Lehm plants USDA FS - Rocky Mountain Research Station Boise, Idaho. 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.