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Weeds of National Significance WILLOW IDENTIFICATION An essential skill for effective willow management Part 1 Intro and Part 2 Supported by the State Government of Victoria. Did you know? Q: How many types of willows are there in the world? Clue: more than 100 have been imported to Australia in the past, so lots more than this. A: More than 300 different species, varieties, cultivars and hybrids > 30 of these are naturalised in Australia New hybrids are forming every day Willow groupings Genus: Salix (all willows) Salix “tree willows” Chamaetia “alpine willows” Vetrix “shrub willows” Did you know? Q: What kind of sportsmen would pay top dollar for a bit of willow wood? Clue: If we got one of these players as our ambassador, our motto could be ‘Waugh on willows’ A: Cricket players Cricket bats are made from the cricket bat willow (Salix alba var. coerulea) Why identify willows? To prevent the future spread and impacts of problem willows: Ease of spread by twigs/branches 1. How brittle are the branches? Why identify willows? Ease of hybridisation and spread by seed • Is it a tree or shrub willow? • Is it male or female or both? • Does it produce viable seed? * For hybridisation to occur and/or seed produced, you must have: • male and female catkins • same subgenus • flowering times overlap ‘Trees’ VS ‘Shrubs’ Features to look for: • form • twigs / branches • bark • leaves • catkins (flowers) ‘Trees’ - form multi-stemmed single - stemmed ‘Trees’ - form upright weeping 10-20m tall at full size ‘Shrubs’ - form always multi-stemmed ‘Shrubs’ always multi-stemmed bark rather smooth (but varies with age) ‘Trees’ - bark Generally rough or fissured Tree - twigs/branches • Crack more easily – Break off the twig/branch at its base How easily and cleanly does it break? ‘Trees’ - leaves and catkins • Long and narrow leaves • Catkins emerge at same time as leaves ‘Shrubs’ - leaves and catkins • Catkins often emerge before the leaves Pussy willows • Both leaves and catkins short and oval-shaped Osiers • Both leaves and catkins long and narrow • Diff from ‘trees’ - often smooth margins along leaf and many stems Form Is this a tree or a shrub? Bark Leaves, stems & flowers Bark Leaves Flowers Twigs Form Form Is this a tree or a shrub? Bark Is this a tree or a shrub? Flowers and leaves? Is this a tree or a shrub? Twigs Is this a tree or a shrub? Grey sallow (Salix cinerea) Leaves? Bark Flowers Form Shrub willow Is it male or female? Twigs
