The stick came with instructions:

I have not grown Dahlia imperialis before. I assume a cutting like this is the quickest way to a blooming-size plant. I picked up three today (presumably it's quite alive...) at the UC-Berkeley Botanical Garden.

For those unfamiliar with the plant, this is the tree Dahlia which grows to 20 feet (typically 8-12 feet). It's a late Fall/Winter bloomer, so it can be tricky in places that get much frost.

Info on Dahlia imperialis:

http://www.anniesannuals.com/signs/d - g/dahlia_imperials_BTD.htm

http://www.smgrowers.com/products/plants/plantdisplay.asp?plant_id=493

Or I see you can buy a small one for $35 on Ebay...

I am looking for rare and unusual (sub)tropicals, either for inside (probably fairly low light) or outside in a frost-free (but coastal/Bay Area California) spot. I already have access to a lot of people and places with interesting plants, so I'm pretty spoiled as far as my choices go.

I posted a second cutting on the plant exchange. I have a third that I will keep and I'll start a post on the tropical section discussion to follow it's progress. I find this an intriguing way to start a new plant fast. I say that partly because it does not seem like a green, alive, flexible cutting, but more like a stiff brown stick.

I do have other things I can root at this point: Deppea splendens, Agapetes serpens, Fuchsia boliviana Alba, Brugmansia sanguinea (blooming), Rhodochiton atrosanguineum, Dicentra scandens, Chlorophytum amaniense 'Fireflash', Philodendron 'Prince of Orange', Monstera deliciosa albo variegata, Homalocladium platycladum, Petunia exserta (seeds), Abutilon megapotamicum, Darmera peltata, Centaurea gymnocarpa, Isopogon formosus, Correa baeuerlenii, Iris confusa, Roldana (Senecio) petasitis, Correa baeuerlenii, Salvia wagneriana, etc...