The effects of the lime aphid, Eucallipterus tiliae L. (Aphididae) on the growth of the lime Tilia × vulgaris Hayne. I. Energy requirements of the aphid population.
The following is virtually the author's summary of this first part of a series on the effects of populations of Eucallipterus tiliae (L.) on two mature lime trees (Tilia × vulgaris) [cf. RAE A 60 320] in Scotland in 1967 and 1968. The energy budgets of the populations were calculated in each year. In each, the aphid population utilised 6% of its energy intake in production (P), 4% in metabolic loss (R) and 90% in defaecation and excretion (F+U). There was little variation in this pattern during the course of the year. The population turned over the energy equivalent of its standing crop on average 482 times a year and the energy drain imposed on the trees by this was 28 055 kcal. Expressed per unit (m2) of ground area covered by the canopy, this is 2672 kcal/year. The influence of this energy drain on lime-tree communities and its implications for woodland ecosystems are discussed.