A reappraisal of the population dynamics of the pine beauty moth, Panolis flammea, on lodgepole pine, Pinus contorta, in Scotland

2000 ◽  
Vol 42 (3) ◽  
pp. 225-230 ◽  
Author(s):  
A. D. Watt ◽  
B. J. Hicks
1985 ◽  
Vol 75 (4) ◽  
pp. 641-651 ◽  
Author(s):  
S. R. Leather ◽  
A. D. Watt ◽  
D. A. Barbour

AbstractAdult females of Panolis flammea (Denis & Schiffermüller) in the laboratory laid more eggs on some provenances of lodgepole pine (Pinus contorta) than on others, even when offered no choice. Their preoviposition period was inversely related to the suitability of the host for larval growth and development. The shorter the preoviposition period the greater the number of eggs that were laid. Delayed mating resulted in reduced fecundity and reduced egg fertility. Female moths lived longest on those hosts on which they oviposited most. Oviposition preferences were correlated with the ratio of the two monoterpenes α- and β-pinene within the host-plants. The effects of provenance, delayed mating and adult mortality were demonstrated through a simulation model; the effect of delayed mating was particularly marked when adult survival was poor. Egg production in the field in Scotland varied from 30 to 123 eggs per female, but this variation could largely be explained by spring temperature. It was concluded that this relationship was due to the influence of temperature on mating and egg laying. The relationship between temperature and egg production forms a basis for predicting damaging levels of Panolis flammea from either pupal or adult numbers. The effects of provenance and delayed mating demonstrate that the frequency of P. flammea outbreaks in the UK may be reduced by the planting of less preferred lodgepole pine provenances and by mating-disruption methods.


2011 ◽  
Vol 41 (12) ◽  
pp. 2403-2412 ◽  
Author(s):  
Daniel M. Kashian ◽  
Rebecca M. Jackson ◽  
Heather D. Lyons

Extensive outbreaks of the mountain pine beetle ( Dendroctonus ponderosae Hopkins) will alter the structure of many stands that will likely be attacked again before experiencing a stand-replacing fire. We examined a stand of lodgepole pine ( Pinus contorta var. latifolia Engelm. ex S. Watson) in Grand Teton National Park currently experiencing a moderate-level outbreak and previously attacked by mountain pine beetle in the 1960s. Consistent with published studies, tree diameter was the main predictor of beetle attack on a given tree, large trees were preferentially attacked, and tree vigor, age, and cone production were unimportant variables for beetle attack at epidemic levels. Small trees killed in the stand were killed based mainly on their proximity to large trees and were likely spatially aggregated with large trees as a result of the previous outbreak. We concluded that the driving factors of beetle attack and their spatial patterns are consistent across outbreak severities but that stand structure altered by the previous outbreak had implications for the current outbreaks in the same location. This study should catalyze additional research that examines how beetle-altered stand structure affects future outbreaks — an important priority for predicting their impacts under climate change scenarios that project increases in outbreak frequency and extent.


2005 ◽  
Vol 35 (6) ◽  
pp. 1314-1318 ◽  
Author(s):  
Peter V Blenis ◽  
Wuhan Li

Infection of lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) by western gall rust has been shown to decrease with tree height and age, but the effects of those two factors have not been separated. Five replicate artificial inoculations were done on a total of 327 trees of different ages in two height classes. Temperature and percentage of spore germination at the height of inoculation, shoot development (stem elongation at the time of inoculation as a proportion of final shoot elongation), main stem leader length at the time of inoculation, tree height, and tree age were measured. Modeled percentages of infected trees and the number of galls per 10 cm of shoot length decreased by 85% and 88%, respectively, as tree age increased between 2 and 10 years, indicating the undesirability of early, aggressive precommercial thinning of lodgepole pine stands in areas where western gall rust is common. By controlling and (or) statistically accounting for inoculum, microclimate, and phenological factors, it was possible to demonstrate that changes in susceptibility with tree age are sufficient to account for the reduction in infection with tree height.


2009 ◽  
Vol 15 (3) ◽  
pp. 535-548 ◽  
Author(s):  
E. A. H. SMITHWICK ◽  
M. G. RYAN ◽  
D. M. KASHIAN ◽  
W. H. ROMME ◽  
D. B. TINKER ◽  
...  

1986 ◽  
Vol 64 (10) ◽  
pp. 2368-2371 ◽  
Author(s):  
Keith N. Egger ◽  
J. W. Paden

Forty isolates of postfire ascomycetes (Pezizales) were tested for in vitro pathogenicity on seeds and germinants of lodgepole pine, Pinus contorta Dougl. Two known pathogens, Caloscypha fulgens (Pers.) Boud. and Botrytis cinerea Pers., were included as a check of the method. Caloscypha fulgens was the only fungus that caused serious declines in seed germination, although several species of postfire Pezizales were capable of preemergence seed infection. Rhizina undulata Fr. and Pyropyxis rubra (Peck) Egger were strongly pathogenic on germinants. Pyropyxis rubra was not previously known to be pathogenic. Many isolates were weakly pathogenic on germinants under the conditions tested.


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