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The sole known metapopulation of Philotiella leona on the Mazama Tree Farm (MTF) and adjacent areas of the Winema National Forest (WNF) in the Antelope Desert of Klamath County, Oregon was surveyed and studied during 2011-2013. The flight period extended from mid-June to mid-late July or early August (35-47 days) with higher temperatures in 2013 associated with the shortest period. Populations of P. leona based on Pollard walk counts were 4-5 X greater at 4 MTF sites than a WNF site. Populations appeared to be twice as large in 2011 than 2012 or 2013. Greatest numbers were seen in late June-early July with a gradual decline thereafter. Flight activity was meandering and low to the ground and mostly occurred after midday, as did mating and oviposition. Nectaring was observed on 9 plant species with Eriogonum umbellatum most favored. A mark, release and recapture (MRR) study was conducted at one location (- 0.4 ha) in the MTF with 214,95 and 105 adults marked in 2011, 2012 and 2013, respectively. Recapture rates of 5.1, 5.3 and 9.5%, respectively, indicated longevity of up to 14 days and yielded population estimates of 61-4515 individuals. Greatest populations of E. spergulinum and P leona appear to be centered on cleared slash/burn sites (like the MRR site) which are linked by trails and tracks. Conservation of P. leona may depend on the periodic creation of trail-linked slash/burn sites which appear to function as sites for sub-populations of a metapopulation.