The morphological responses to changes in environment quality showed by many clonal plants have been interpreted as an expression of foraging behaviour, as they allow the ramets become concentrated in more favourable microhabitats. The morphological response to increased nutrient availability in the pseudoannual plant Trientalis europaea was studied in a field experiment. The morphological response was largely size-dependent and consistent with an enhanced clonal growth. Fertilized ramets produced more tubers and a larger main tuber. In contrast, stolon length was not affected by the treatment.
The effectiveness of the foraging response was examined in a spatially explicit simulation model calibrated with data of the field experiment. The model showed that T. europaea was effective at concentrating its ramets in favourable patches, but this was mainly due to the enhanced performance of clones initially located in the favourable patches. In these clones, the interaction between increased ramet size and increased survival accelerated the production of ramets. This process was, however, strongly influenced by patch size. The temporal and spatial scale at which the foraging response of T. europaea was manifested suggests that the foraging behaviour in this species should be favoured by a high spatio-temporal predictability in the environment. Overall, our model emphasized the important role of populational aspects to understand the dynamics of the foraging response.