1 The pine beauty moth, Panolis¯ammea, has been a serious pest of lodgepole pine plantations in Scotland since 1976. It historically feeds on native Scots pine throughout Europe but population levels of P.¯ammea on this host have never been high enough to cause tree mortality in the U.K. 2 This paper reviews recent advances in the biology of the pest and documents control programmes from 1976 to 1999.

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The pine beauty moth, Panolis flammea, is a defoliating pest of lodgepole pine (Pinus contorta) forests in Scotland. This article reviews early and recent research on the population ecology of Panolis flammea and presents an analysis of pupal survey data collected between 1977 and 1993. Research in the 1980s suggested that natural enemies, although effective in preventing P. flammea outbreaks on Scots pine (Pinus sylvestris), played an insignificant role in the population dynamics of P. flammea on lodgepole pine. However, analysis of pupal survey data showed that delayed density‐dependent action of natural enemies, probably parasitoids, was overlooked during the 1970s and 1980s. Recent research suggests that fungal pathogens are responsible for a decline in the frequency and severity of outbreaks of P. flammea on lodgepole pine. This suggestion, together with the overlooked importance of other natural enemies, indicates that the population ecology of P. flammea in Scotland has changed during the past 20 years and requires a full reappraisal.

In the United Kingdom, Panolis flammea (Den. and Schiff.) (Lepidoptera: Noctuidae) is an important pest species of the introduced lodgepole pine but not of its natural host Scots pine. The timing of P. flammea larval growth must be synchronized with its host tree if the larvae are to succeed. We collected field data during 1990 which revealed that the phenological window starts earlier in Scots pine and is shorter than that observed in lodgepole pine. The larvae are found in the field earlier and within a narrower time frame within a Scots pine forest than in a lodgepole pine forest. The larval developmental period is significantly longer on lodgepole pine than on Scots pine. The synchrony/asynchrony of P. flammea to its natural host (Scots pine) and an introduced tree (lodgepole pine) results in the parasitoids having a different impact on the larvae of the two hosts. At any one time, the host plant, caterpillars and parasitoids are more synchronous on the ancestral Scots pine than on lodgepole pine, resulting in a higher percentage of larvae in the optimal instar for parasitism at that time. In lodgepole pine, the percentage of suitable instars available to parasitoids is lower at any given time. The information presented here furthers our understanding of the possible mechanisms for the observed differential population dynamics of the insect on Scots pine and lodgepole pine in the UK.

The effectiveness of topical applications of the juvenile hormone analog Fenoxycarb against selected developmental stages of the eastern spruce budworm, Choristoneura fumiferana (Clemens), was determined. Eggs at an early stage of embryogenesis (0–24 h old) were prevented from hatching and were more sensitive to the compound than older eggs (48–72 h old) and larval stages. Fifth-instar larvae displayed lethal morphogenetic effects following Fenoxycarb treatment, but third-instar larvae were refractory. Adult females constituted the most sensitive stage; treated insects laid eggs that failed to hatch. Untreated adult females that mated with Fenoxycarb-treated males also laid infertile eggs.