Factors affecting willow leaf beetles (Phratora vulgatissima) when selecting overwintering sites

Abstract

1 Leaf beetles are major pests in willow plantations used as short-rotation coppice for biomass production. The beetles overwinter mainly outside the plantations. An understanding of the factors affecting adult leaf beetles seeking overwintering sites may provide information that could be valuable when developing methods to control the beetles. 2 We conducted a field experiment in a willow plantation with a high abundance of the leaf beetle, Phratora vulgatissima. We positioned overwintering constructions (OWCs) made out of bundles of reed (Phragmites australis) outside the plantation. 3 Leaf beetles preferred (i) to fly towards silhouettes; (ii) OWCs positioned 1.5 m above the ground compared with ones 0.5 m above the ground; (iii) OWCs orientated vertically compared with OWCs orientated horizontally; and (iv) reeds of a diameter of approximately 5 mm. 4 Leaf beetle size was not correlated with reed diameter. 5 It is concluded that the leaf beetle P. vulgatissima selects an overwintering site based on factors at both larger and smaller scales. The possibilities for using OWCs made of reed bundles as tools to monitor and control are discussed.

How far away is the next basket of eggs? Spatial memory and perceived cues shape aggregation patterns in a leaf beetle

“…), and these beetles are the most common specialist herbivore of willow in Europe (Peacock and Herrick 2000). Adults overwinter in reeds or under the bark of trees (Bjo¨rkman and Eklund 2006), emerge in April, feed for about two weeks, mate, and subsequently lay hundreds of eggs on the undersides of leaves in clutches of 1-50 eggs. Hatching larvae feed gregariously during the first and second instar and then solitarily on different leaves during the third instar (Kendall et al 1996).…”

Overwintering sites of the Japanese carrion beetle Eusilpha japonica

“…Consequently, we conclude that E. japonica beetles prefer soils near trees as overwintering microhabitats. Ladybird beetles Coleomegilla maculate are known to utilize different habitats between seasons (Nault and Kennedy 2000), and willow beetles Phratora vulgatissima move into cracks and crevices before overwintering (Björkman et al 2004;Björkman and Eklund 2006). Olive weevils Dyscerus perforates overwinter on the ground surface within 50 cm of the base of tree trunks (Ichikawa et al 1991), and spider mites Neoseiulus fallacies and riparian ground beetles Bembidion petrosum move from moist to dry microhabitats before overwintering (Epstein and Kulman 1990;Ishitani and Yano 1994;Yamazaki et al 1999;Anderson 2006).…”

“…Most studies on habitat preference focus on spatial distribution and behavior during the developmental season (e.g., Luff et al 1989;Rushton et al 1991). Information on overwintering sites is limited mainly to agricultural pests (e.g., Ichikawa et al 1991;Nault and Kennedy 2000;Björkman et al 2004;Björkman and Eklund 2006). Few studies have investigated how and where common carrion beetles overwinter.…”

Consumptive and nonconsumptive effect ratios depend on interaction between plant quality and hunting behavior of omnivorous predators

“…In plantations, used for biomass production, outbreaks can reduce growth by up to 40% (Björkman, Höglund, Eklund, & Larsson, 2000). Adults overwinter in shelter-providing vertical objects like reeds or trees with aging bark (Björkman & Eklund, 2006), emerge in April, feed for about 2 weeks, mate and subsequently lay hundreds of eggs on the underside of leaves in clutches of 1-50. Larvae hatch after 15-20 days and feed gregariously on leaves during the first and second instars and then solitarily during the third instar (Kendall, Wiltshire, & Butcher, 1996).…”