Hastings Natural History Reservation

16 May, 05 AM - 21 May, 02 AM

This project aims to improve our understanding of the germination strategies used by native annual plant species and how these strategies impact the success of individual species in competition with invasive grasses and under likely climate change scenarios. Specifically, we will be examining the reliance of individual species on seed banks and germination temperature cues across species? geographic ranges in California. We will use this information to examine: 1) how germination strategy impacts the ability of native forbs to compete with exotic grass species, 2) whether there is evidence that germination strategies have adapted in agricultural environments and to different rainfall patterns across their ranges, 3) whether germination strategy adaptations have occurred in certain phylogenetic groups or species with heavier reliance on seed banking or temperature cuing, and 4) How species with different germination strategies are likely to fair under climate change models for California. For this project we will be collecting seeds from 70 species found in the following plant families: Lamiaceae, Schrophulariaceae, Polemoniaceae, Onagraceae, Papaveraceae, Boraginaceae and Asteraceae. All species included in this study are common and found in a range of habitats within the California floristic province and the Mojave Desert. There are three field components of this study which I hope to do at this and other reserves: 1) seed collection, 2) seed survival rate assessment, and 3) collection of soil cores. I hope to do all three components of this study at 11-13 UC reserves and 5 non-UC reserve locations. No one reserve contains all species that I am including in this study, thus at any one reserve I will only be collecting seeds from between 10 and 40 species. For ease of statistical analysis, I will be collecting seeds from individual plants and hopefully from more than one population from each reserve. The total number of seeds collected per population will vary depending on seed production rates in each species. To assess seed mortality after one year in the soil, I will place a set number of seeds in cloth bags, which I will then bury in the soil. These seeds will be buried at the time of seed collections. I will return to dig up the bags in September of 2006. Bags will likely contain ~ 100 seeds so their presence should have little impact on burial sites. All buried seeds will originate from the same location as they will be buried. The final component of this study is an assessment of seed bank size in at least one population in each sampling location for 40 of my focal species. To do this, I will collect soil cores from sampled populations for the 50 focal species. I will take soil cores back to the UCSB campus where I will water collected soil cores along with a known number of seeds from each species, under constant light and water conditions in greenhouses. The number of seeds from each species that sprout from each soil core will then be used to assess the seed bank size of each population. I plan to collect soil cores in March, when populations of each species are still blooming, ensuring that the tested seed banks do not include seeds from this year. While I ideally need to collect a large number of seeds from each population (1000-2000) I will not collect all seeds from any single population nor will I take all seeds from individual plants. Due to the large number of species included in this study, I also will not be taking more than 5-10 small (3-4 inch diameter) shallow (2 inch deep) soil cores from any single location, thus the impacts of this study on local plant communities should be small.

Visit #10054 @Hastings Natural History Reservation

Approved

Under Project # 6359 | Research

Germination Strategies of native California forbs

research_scientist - University of California, Santa Barbara

Reservation Members(s)

Margie Mayfield May 16 - 21, 2006 (6 days)
Margie Mayfield May 16 - 21, 2006 (6 days)

Reserve Resources(s) | Create Invoice

Stucco House 2 May 16 - 21, 2006