Valley Flora Propagation Center Species Profiles

Author: Brianna Borders
Other Contributors: Nur Ritter, Justine Kokx, Adrian Howard, and Graham Biddy

Introduction

From 2001-2008, the California State University, Stanislaus' Endangered Species Recovery Program (ESRP) operated a native plant seed production program in support of efforts to restore retired agricultural lands in western Fresno County, California. The seed production program was established with funding from the United States Department of Interior's Land Retirement Program.

In these species profiles, we describe our planting, seed harvesting, and seed processing methods, summarize our phenological observations, display numerous photos, and describe both the successes and the obstacles that we encountered during our efforts to propagate the species. In addition to summarizing our experience with cultivating each species, we have included, when available, a list of references in the scientific literature, and links to Internet resources that feature photos, propagation advice, and species profiles that have been compiled by other organizations.

Many species performed well at the nursery; they germinated readily, grew vigorously, and reliably produced seed. However, we are cautious in recommending a species for use in local restoration activities based on its performance at the nursery. In several instances, species that performed well in the nursery (e.g., Frankenia salina, Heliotropium curassavicum, Lasthenia chrysantha) did not perform well when they were seeded in local restoration trials. Though the site conditions (e.g., highly modified soil structure, elevated soil salinity, fine-textured soils, and low annual precipitation) at the nursery are similar to those of the retired agricultural lands, species in cultivation at the nursery benefited significantly from weed control and irrigation. The growing conditions at a restoration site are far more rigorous (i.e., significantly less weed control, and little, or no, irrigation) than the conditions at the nursery, and have been demonstrated to limit the success of native species establishment (Ritter and Lair 2006).


Profiles

Updated 2010-05-06

PDF Species ProfileCommon NameFamilyLife History
Achyrachaena mollisblow wivesAsteraceaeannual herb
Allenrolfea occidentalisiodinebushChenopodiaceaeshrub
Amsinckia vernicosagreen fiddleneckBoraginaceaeannual herb
Asclepias fascicularisnarrow-leaved milkweedAsclepiadaceaeannual or perennial herb
Astragalus oxyphysusMt. Diablo milkvetchFabaceaesub-woody perennial
Atriplex polycarpaallscale saltbushChenopodiaceaeshrub
Atriplex spiniferaspinescale saltbushChenopodiaceaeshrub
Castilleja exsertapurple owl's cloverScrophulariaceaeannual herb
Clarkia purpureapurple clarkiaOnagraceaeannual herb
Daucus pusillusAmerican wild carrotApiaceaeannual herb
Eremalche parryiParry's mallowMalvaceaeannual herb
Frankenia salinaalkali heathFrankeniaceaeperennial herb
Grindelia camporumgumplantAsteraceaeperennial herb
Gutierrezia californicaCalifornia matchweedAsteraceaeperennial herb
Guillenia lasiophyllaCalifornia mustardBrassicaceaeannual herb
Hemizonia pungenscommon spikeweedAsteraceaeannual herb
Hutchinsia procumbensprostrate HutchinsiaBrassicaceaeannual herb
Isocoma acradeniagoldenbushAsteraceaeshrub
Isomeris arboreabladderpodCapparaceaeshrub
Kochia californicarusty mollyChenopodiaceaeperennial herb
Lasthenia chrysanthaalkali goldfieldsAsteraceaeannual herb
Lessingia glanduliferavalley lessingiaAsteraceaeannual herb
Lupinus succulentusarroyo lupineFabaceaeannual herb
Malacothrix coulterisnake's headAsteraceaeannual herb
Madia eleganscommon madiaAsteraceaeannual herb
Mentzelia laevicaulissmooth-stem blazing starLoasaceaeperennial herb
Monolopia strictaCrum's monolopiaAsteraceaeannual herb
Oenothera deltoidesdesert lanternOnagraceaeannual herb
Phacelia ciliataGreat Valley phaceliaHydrophyllaceaeannual herb
Phacelia tanacetifoliatansy-leafed phaceliaHydrophyllaceaeannual herb
Salvia columbariaechiaLamiaceaeannual herb
Suaeda moquiniibush seepweedChenopodiaceaesub-woody perennial
Trichostema ovatumSan Joaquin bluecurlsLamiaceaeannual herb
Wislizenia refractajackass cloverCapparaceaeannual or perennial herb

Background

When propagating plants for ecological restoration, it is important to try to prevent shifts in population genetic composition, in order to maintain genetic variability (Meyer and Monsen, 1992). Therefore, we endeavored to avoid bias towards any particular plant traits and to minimize the potential for artificial selection. We did not fertilize the plants or use any soil amendments (e.g. organic matter, salt remediation products, mycorrhizal inoculants). We did not water the plants on a regular basis. However, we occasionally irrigated the nursery in response to seasonally low rainfall. We collected seeds from entire planted populations without regard to individual plant size, vigor, or seed output (McKay et al., 2005). Whenever possible, we collected seeds on multiple dates during the collection window, in order to capture both early and late maturing genotypes (Knapp and Rice, 1994, McKay et al., 2005). We did not re-plant nursery-produced seed for more than four successive generations (Smith et al., 2007). However, our continuous weed removal efforts likely exerted some selective pressure on the cultivated plants, by reducing competition from weed species.

The best way to avoid genetic shifts during propagation is to increase seed in an environment as similar as possible to the target site, i.e., the site to be restored (Knapp and Rice, 1994). If plants are grown under conditions that are dissimilar to that of the target environment, the different selective pressures may result in seed that is adapted to the growing environment rather than the restoration site (Knapp and Rice, 1994).

The nursery site was formerly used for irrigated agriculture and is located within the drainage-impaired portion of the western San Joaquin Valley. Therefore, the nursery site shares a similar history of disturbance with the tracts of retired farmland for which restoration has been proposed. Site characteristics resulting from disturbance associated with agricultural production include highly modified soil structure, shallow water tables, elevated soil salinity, and prevalence of non-native weedy species. Inherent site characteristics shared by the nursery and the retired farmlands include a semi-arid climate and fine-textured soils.

The seeds that we planted in the nursery were collected from native plant populations located within an 80-km radius of the nursery site. Whenever possible, we collected seed from at least 50 individuals per wild population. However, for some species, the seeds planted in the nursery were collected from a small number of individuals (e.g., less than 10).

When we initiated the seed production program, information on propagation, harvesting, and seed processing techniques was non-existent or insufficient for a majority of our targeted native species. Therefore, we needed to learn the phenological patterns (e.g., timing of germination, flowering period, seed ripening period, and seed collection window) of numerous species. We developed seed harvesting and processing methods for many species, within the constraints of available equipment and staff time. We also had to experiment with various weed control methods and respond to setbacks and complications that included insect damage, the threat of trespass sheep grazing, drought conditions, vandalism, and wildlife herbivory.

Over the course of the project, the nursery ranged in size from approximately 1.1 to 1.6 hectares (2.7 to 3.9 acres). Due to the relatively small scale of the nursery, we did nearly all of the planting and seed harvesting by hand. By our definition, a growing season began in the fall when seeds of annual species were planted and ended during the next fall, when seed harvest from warm season annual species was completed. Therefore, a growing season spanned two calendar years.

For a more comprehensive description of ESRP's native plant seed production program, please refer to the document, 'A Synthesis of Native Plant Seed Production Efforts in the San Joaquin Valley, California.' For more background on the Land Retirement Program, please visit: http://esrp.csustan.edu/projects/lrdp/landretirement/

Other Resources

Other valuable Internet resources for information on California native plants include:

References

Knapp, E. E., and K. J. Rice. 1994. Starting from seed: genetic issues in using native grasses for restoration. Restoration and Management Notes 12:40-45.

McKay, J. K., C. E. Christian, S. Harrison, and K. J. Rice. 2005. "How local is local?" - A review of practical and conceptual issues in the genetics of restoration. Restoration Ecology 13:432-440.

Meyer, S. E., and S. B. Monsen. 1992. Genetic considerations in propagating native shrubs, forbs, and grasses from seed. Pages 47-54 in Proceedings of the Western Forest Nursery Association Meeting. General technical report RM-221. U.S. Forest Service, Fort Collins, Colorado.

Ritter, N.P., and K. D. Lair. 2006. A synthesis of restoration research conducted near Tranquillity, California. United States Department of the Interior-Interagency Land Retirement Team. Fresno, CA. 57 pp. Available from: http://esrp.csustan.edu/

Smith, S. L., A. A. Sher, and T. A. Grant. 2007. Genetic diversity in restoration materials and the impacts of seed collection in Colorado's restoration plant production industry. Restoration Ecology 15:369-374.