L and T dwarfs in the Hyades and Ursa Major moving groups

We have used the moving cluster method to identify three L dwarfs and one T dwarf in the Ursa Major/Sirius moving group (age 400 Myr). Five L dwarfs and two T dwarfs are found to belong to the Hyades moving group (age 625 Myr). These L and T dwarfs define 400- and 625- Myr empirical isochrones, assuming that they have the same age. Moving group membership does not guarantee coevality.