I too love cascades, but good ones are hard to find. Most of the time when I create a cascade from purchased material, it is being sold/advertised as an informal upright. You must use your "bonsai vision" to see the potential in these trees to BECOME a cascade, or find the trees that easily lend themselves to this style. As for vendors I'm sure you could do this with just about any nursery. I myself have purchased multiple cascades this way from nurseries, vendors, auctions, and member sales areas of bonsai shows. These member sales areas often have material that has been given up on or forgotten about, the owners simply losing interest or motivation, and they can usually be purchased for little money (this is my secret to getting quality material for cheap
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