This subtask can be divides in 2 topics : 1 - Quality of plants grown in nursery from seeds (COILLTE, NFV,CEMAGREF) Physiology of tree seedlings in relation to plantation establishment. Test of different methods of growing the planting stock (bare-root, container) Study of an other way to produce bare-root conifers : undercutting instead of transplanting. 2 - Vegetative propagation of clones (CEMAGREF, SRFGX) - Stock plant management -Propagation of mature material by cuttings -Vegetative propagation of Hybrid larch