PERFORMANCE OF VEGETATIVELY PROPAGATED LARIX-DECIDUA, L-KAEMPFERI AND L-LARICINA HYBRIDS

Interspecific hybridization between the tamarack and the Japanese and European larches was attempted. Successful crosses between the tamarack and the Japanese larch as well as the 3-way hybrid (tamarack crossed to European x Japanese larches) were obtained for the first time in France but on a limited scale. Hybridization with tamarack seems possible but rather difficult due to differences in phenology and reproduction potential. Hybrid clones were successfully propagated by stem cuttings with high rates of rooting and a good quality of the root system, especially for the tamarack and its hybrids. Field performances at 8 years reveal that even if their initial growth is vigorous is absolute terms, neither the tamarack nor its hybrids could compete with the hybrid Larix decidua x L kaempferi for both growth and stem form. One exception is the 3-way hybrid L laricina x (L decidua x L kaempferi) which can be advantageously compared to the latter. An additional advantage could be its expected greater tolerance of wet soils. Nevertheless, its creation appeared to be difficult. So far, the hybrid L decidua x L kaempferi seems to be best for reforestation.