Regeneration of Rocky Mountain bristlecone pine (Pinus aristata) and limber pine (Pinus flexilis) three decades after stand-replacing fires

Limber Pine Regeneration and White Pine Blister Rust in the Central and Southern Rocky Mountains

“…Limber pine seedlings occurred more often with noncompeting ground cover types, litter, and rock and less often with grass than in random areas, which is consistent with the results of Jones (1967), Schoettle (2009), andLooney andWaring (2012). Grass was also negatively associated with limber pine seedling density.…”

“…A variation in density exists between the studies because counted seedling clumps as one unit (seedling sites) and we differentiated individual stems, even if clumped. Our mean seedling densities for study areas on the Front Range of Colorado (96 and 194 stems ha Ϫ1 ) are very low in comparison with studies of limber pine regeneration in existing stands lacking recent fire (492 stems ha Ϫ1 ) and sites postfire on the Front Range of Colorado, which range from 290 to 508 stems ha Ϫ1 (Shankman andDaly 1988, Coop andSchoettle 2009). Overstory basal area and density of live limber pine Ն1.37 m tall in the same evaluated plots as in this study were 5.8 m 2 ha Ϫ1 and 311 stems ha Ϫ1 , which were also low in R 2 value obtained using PROC REG with /best ϭ 5 selection ϭ rsquare b, and applies only to the fixed effects.…”

“…Microsite objects have been shown to provide some protection for development of seedlings and may be particularly important in harsh sites and the upper treeline (Maher and Germino 2006). Coop and Schoettle (2009) found a strong association between microsite objects and seedlings in sites postfire, but object type did not matter. Like Coop and Schoettle (2009), limber pine seedlings were located more often next to microsite objects, particularly rocks or trees, versus the random areas.…”

“…Understory vegetation may compete for growing space-limiting regeneration (Looney and Waring 2012), or it may facilitate establishment by providing protection (Maher et al 2005). Microsite or nurse objects such as logs or rocks may also offer physical protection to developing seedlings (Tomback et al 1993, Coop andSchoettle 2009). Because of low tree density and bare soil surface, open-canopy stands of limber pine offer suitable habitat for recruitment (Webster and Johnson 2000).…”

Deadwood anisotropic facilitation on seedling establishment after a stand-replacing wildfire in Aosta Valley (NW Italy)

“…The presence of abiotic shelter elements can potentially provide safe microsite conditions for recruitment, without producing competition dynamics with the seedlings. Nurse objects can enhance both seedling establishment and survival (Coop and Schoettle, 2009;Resler et al, 2005;Castro et al, 2011). They can efficiently act as traps for wind-dispersed seed, and provide shading, resulting in reduced evaporation and higher soil moisture (Flores and Jurado, 2003;Carlucci et al, 2011).…”