In oak, sequencing has been performed on the 5'-end of about 50,000 cDNAs from non-normalized libraries, cloned in the pBlueScriptIISK vector). High quality sequences were been obtained as follows: Quercus robur roots, 19177 ESTs; Quercus robur leaves, 7097 ESTs; Quercus robur differentiating xylem, 9529 ESTs; Quercus petraea buds, 9990 ESTs. The average size of the inserts in the cDNA libraries is about 1 kb. These ESTs were analyzed and annotated using the EPA bioinformatics pipeline (http://cbi.labri.fr/outils/SAM2/). A unigene set of 16,000 elements is now ready to be printed on a micro-array. These will be produced in the frame of the EVOLTREE Network of Excellence. This resource will serve as the basis for the development of a research programme focused on two adaptive traits in oaks: drought response and vegetative bud break. Furthermore, this resource will be used to understand the molecular mechanisms implicated in the differentiation of oak species (Q. robur and Q. petraea), notably their capacity to support flooding of their root systems. Finally, SSR and SNP databases were constructed based on in silico ming on the ForEST data. They will support genetic and comparative mapping activities in the Fagaceae family within EVOLTREE. In 2007, the oak EST catalog will be extended to 150,000 new ESTs (EVOLTREE project).