How to kill it
Early detection and eradication is very important with this willow. Begin control at the top of a catchment. Treat every stem.
1. Cut and squirt (summer-autumn): make 1 cut every 100mm around the trunk and saturate with undiluted glyphosate (10 ml) or 2, 4-D ester (20 ml).
2. Cut stump application: apply picloram gel. Remove all plant material from site as all cut stems can root where they fall.
3. Bore and fill (summer-autumn): make 1 hole every 100 mm around the trunk and saturate each hole with undiluted glyphosate (10ml) or metsulfuron-methyl 600g/kg (2ml of 20g/l) or undiluted 2,4-D ester (20ml).
4. Frilling (summer-autumn): glyphosate (100ml/l) or 2,4-D ester (200ml/l).
5. Spray ( full leaf stage only): glyphosate (12.5ml/l + penetrant, total coverage needed) or metsulfuron-methyl 600 g/kg (35g/100l from January to April before leaf fall begins).