Im from California (sunny Sacramento) too but your the only person ive heard say that they are a weed . I wouldn't even consider them as such,as i have never seen them grow wildly and uncontrolably anywhere.we must be from different areas definitely

Hello Todd
propagation on the callas there is a couple of ways one is by seeds which is hidden in the splathe,after they are pollinated the spathe turns green and as the berries rippen the spathe rots away leaving the berries on a stem these are your seeds.(the spathe is the petal looking modified leaf that surround the spadix ,the spadix is the yellow spike lin the center .It contains tiny male and female flowers the pollinating male flowers on the top part of the spadix and the femal are located on the lower part) also propagation can be from rhizomes/tuber (swollen roots)which grows more rhizomes which can be seprated to grow more plants . after the plant has flowered that is when its usally in the process of this just keep taking care of the plant and in fall before winter sets in you can dig up and see your harvest .

Hope this helps alittle
happy Gardening
Debby in 106 degree weather in sunny Californina
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