December 1, 2014

Developing reintroduction techniques for Lomatium cookii

Thomas N. Kaye, et al. | 2013

The goal of this project was to develop reintroduction techniques for Lomatium cookii to support recovery of the species. The specific objectives of this study included: determining survival and growth of new

The goal of this project was to develop reintroduction techniques for Lomatium cookii to support recovery of the species. The specific objectives of this study included: determining survival and growth of new individuals propagated from both seeds and root plugs, observing the effects of litter removal on  L. cookii transplant survival, testing for local adaptation of seeds sources, comparing survival and growth rates of introduced to native L. cookii populations, as well as to collect seeds and establish a seed increase program.

Direct seeding and transplanting appear to be useful methods for reintroducing populations of Lomatium cookii. The augmentations conducted in this study at three locations, French Flat ACEC, Reeves Creek, and Agate Desert Preserve resulted in establishment, survival, and growth of substantial numbers of plants in some cases, although subsequent mortality at Agate Desert was relatively high.

Transplants fared better at French Flat than Agate Desert from 2008 to 2011. Transplants at Agate Desert had less than 5% survival by 2011. In general, older and larger plants survived better, especially if they had been fertilized while grown in the greenhouse (and therefore had higher biomass) or were grown in potting soil inoculated with local soil.

More transplants grew to large reproductive plants, and in a shorter time frame, than seeded plants. Transplants from French Flat produced a total of 193 (61 large) reproductive plants from 2008-2013, while seeded L. cookii at French Flat produced only 70 (15 large) reproductive 30 plants from 2006-2013. Recruitment of seedlings was also observed in many transplant plots at French Flat (and Agate Desert) by 2010.

Leaf litter and planting habitat appear to affect seedling establishment at some sites, particularly at site which had relatively thick litter layers.

When seeds from French Flat and Agate Desert were both sown at French Flat on serpentine- influenced soils, first year establishment was nearly equal (13-15%). However, mortality after 2007 was higher for seeds from Agate Desert, suggesting that there may be some local adaptation of French Flat plants to the serpentine environment. Seedling survival may be reduced for nonlocal genotypes, while growth of larger plants may be unaffected. However, other factors may also be at play, such as herbivory from voles. Regardless of the mechanisms involved, at this time it appears that there is some evidence for local adaptation of L. cookii to conditions at French Flat.