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Untreated firewood can harbor destructive insects and pathogens and transport them to uninfested areas. In a national survey of retail locations selling firewood in 18 states, over half (52%) of the firewood was from sources out of the purchase state and 50% showed evidence of insect infestation. In a three state survey of southern Rocky Mountain retailers, the most common retailer types carrying firewood were grocery stores and department or big box stores followed by gas stations or convenience stores. In 2007-2009, we purchased 419 firewood bundles from retailers in Colorado, New Mexico, Utah, and Wyoming and caged the firewood to quantify insect emergence. Live insects emerged from 47% of firewood bundles over 18 mo of rearing time. Approximately 11 insects emerged on average from each infested bundle (1-520 per bundle). Pine, fir, and mixed-conifer bundles yielded the greatest number of insects. Beetles (Coleoptera) were prominent and made up the majority of individuals (3-60 individuals in each of 24 families). Most Coleoptera were bark and ambrosia beetles (subfamily Scolytinae) while wood borers (Buprestidae, Cerambycidae, Siricidae) occurred in lower numbers. Firewood with evidence of previous or current insect infestation was more likely to have insects emerge than firewood without such evidence. The risk of moving live native or nonindigenous insects in untreated firewood is high because insects emerged up to 558 d from purchase date. Retail firewood should be heat treated in a manner to eliminate insects that is uniformly accepted across North America.

Mountain pine beetle (MPB) and white pine blister rust (WPBR) cause mortality in limber pine and limber pine seedlings in Colorado, Wyoming, and Montana, USA. Seedlings can be killed rapidly by WPBR, and WPBR and bark beetles reduce cone and seed availability. In 2011 and 2012, we assessed occurrence, abundance, recent growth, and health status of limber pine seedlings in stands affected by WPBR and MPB. We determined biotic and abiotic factors influencing limber pine seedling density and terminal growth, and proportion of limber pine seedlings with WPBR. Live seedling density averaged 141 stems ha Ϫ1 and ranged from 0 to 1,935 stems ha Ϫ1 . Blister rust was the primary damage agent with 0 to 100% incidence. Diseased seedlings occurred on 30% of all plots. Seedling density was predicted by limber pine tree density, total tree density, percent ground cover as grass, and seedling height. The proportion of limber pine seedlings with WPBR was related to limber pine seedling height, cankers ha Ϫ1 , percent crown dieback of overstory, and density of trees with WPBR. Monitoring and restoration of stands, including planting on sites with adequate moisture and near objects with some overstory cover, are needed to ensure limber pine regeneration on some sites.

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