
Salix (likely; species tbc)
Volunteer from the Berberis pot, with a smaller sibling (Mysterion 2). A woody seedling with a red stem and oval, pointed, finely toothed leaves. The flat, single-scaled buds and the stipules point to a willow; species tbc.
Willows grow fast and root easily, which makes for a quick, forgiving bonsai project.
A garden tree only where there is plenty of room, well away from drains and walls.
Leaf and bud close-ups point to a willow, not a cherry: flat buds pressed to the stem under a single scale, with a pair of stipules at each leaf. Species tbc. A white woolly blob at one leaf joint, probably woolly aphid, to be wiped off.
Removed crispy leaves and dead stems, trimmed away the definitely dead parts of the remaining leaves, and moved to a sheltered spot.
Lifted out of the Berberis pot, potted into a small pot of compost with perlite and moved into the unheated greenhouse. Turned out to have a sibling, now Mysterion 2.
Roots were tangled into the Berberis roots and ran surprisingly deep, so some were lost, but a good root ball came out intact.