Propagation and reintroduction for Lupinus oreganus in the BLM, Roseburg District

EXECUTIVE SUMMARY

This document reports initial work from seed collection, propagation, and outplanting of Lupinus oreganus for the Roseburg District Bureau of Land Management. Sites managed by the Roseburg BLM represent the southernmost range of this threatened plant species. Three sites were outplanted including Callahan Meadows (approx. 1,900 plants), Loose Laces (approx. 1,075 plants), and Stout’s Creek (approx. 750 plants).

Seeds collected in 2005, 2011 and 2016 from four source populations were stratified and grown by IAE staff in the winter/spring of 2016-2017. Of the 6,920 seeds started in December 2016, approximately 3,725 were outplanted in April of 2017. Seeds were collected from China Ditch, Dickerson Heights, Loose Laces, and Stouts Creek.

Seeds were scarified and then placed in cold-wet stratification for 4 weeks. After cold stratification seeds were removed to warm greenhouse conditions to break dormancy (though nearly all seeds broke dormancy in cold).

Germinated seeds were inoculated with species specific rhizobium and potted into 10” Ray-Leach conetainers. After ~12-16 weeks in the greenhouse, plants were transferred outdoors to harden off for 1-2 weeks. Hardened individuals were then transferred to field sites and outplanted using both dibbles and hand tools.

A subset of L. oreganus at each site were outplanted into a grid to facilitate monitoring. Initial survivorship of these plants approximately eight weeks post-outplanting was above 90% at all three sites.

Information about mortality and survivorship from germination to outplanting will be valuable in determining plant material needs for future reintroduction efforts for L. oreganus in Douglas County.