Synoptic climatology of the long-distance dispersal of white pine blister rust II. Combination of surface and upper-level conditions

Abstract

An invasive forest pathogen, Cronartium ribicola, white pine blister rust (WPBR), is believed to have arrived in the Sacramento Mountains of south-central New Mexico about 1970. Epidemiological and genetic evidence supports the hypothesis that introduction was the result of long-distance dispersal (LDD) by atmospheric transport from California. This study applies a method to identify the atmospheric conditions favorable for rust transport and infection. An upper level synoptic classification (ULSC) identifies patterns of upper-level flow favorable for the transport of rust spores from a source to a target. Transport data are coupled with data for surface conditions favorable for infection at a designated target. A resulting calendar lists likelihood classes for establishment by four-times-daily observations during a dispersal season from April through July in the years 1965 to 1974. The single most-favorable period for transport and infection at the New Mexico site was identified as 1-15 June 1969. Five additional sites in the western United States with susceptible white pine populations and known infestation status were then evaluated to verify the model. Only the infested sites exhibit an establishment likelihood of "high" or "very high." This suggests that the methodology correctly identifies locations with elevated establishment likelihood. Finally, likelihoods at nine additional points in the southwestern United States are determined and used to map regional patterns of transport, infection and establishment. The ULSC combined with appropriate surface meteorological data could be used to further investigate transport and infection, identify other areas at risk, assess the potential for gene flow of WPBR and evaluate long-distance dispersal of other pathogens.

Risk of white pine blister rust to limber pine in Colorado and Wyoming, USA

“…From past reports and our observations, pathogen spread across the region appears as both erratic, long-distance jumps and a regular dispersal to the next nearest host population (Brown 1978;Blodgett and Sullivan 2004;Kearns and Jacobi 2007;Frank et al 2008). From past reports and our observations, pathogen spread across the region appears as both erratic, long-distance jumps and a regular dispersal to the next nearest host population (Brown 1978;Blodgett and Sullivan 2004;Kearns and Jacobi 2007;Frank et al 2008).…”

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

“…Infection occurs through the needles of susceptible white pines during late summer and fall under conditions of high relative humidity and causes branch and stem girdling cankers. Aeciospores produced on pines are durable and can occasionally be windblown several hundred kilometers via atmospheric transport to infect alternate hosts' leaves (Frank et al 2008). Infective, less durable basidiospores produced in late summer to autumn on the leaves of the alternate hosts may be windblown up to 27 km to the susceptible pines (Zambino 2010).…”

Synoptic climatology of the long-distance dispersal of white pine blister rust. I. Development of an upper level synoptic classification

“…This methodology can help to spatially and temporally model the long-distance dispersal of airborne pathogens and aerosols. For example, in related work, Frank et al (2008) use the ULSC to assess the relative frequency by which white pine blister rust may be transported from source populations in the Sierra and Cascade ranges to target populations in the interior southwest. The ULSC clusters provide a ranking of the spatial connection between sources and targets by representing potential pathways for the atmospheric transport of rust spores.…”