If you want to order a beer in a Spanish bar you might be tempted to say ‘una cerveza por favor’ and you would be given a bottle of your favourite tipple. To avoid misunderstandings and disappointment, it might be better to ask for the bottle of your choice by name, i. e. ‘una Estrella por favor’ or ‘un San Miguel‘. But, if what you really want is a half a pint, or a draught, you must ask for ‘una caña‘. The expression refers to the cylindrical shape of the glass, I believe.
The original meaning of caña is a different one though, and don’t ask me if and why the two should be related. Caña is the name for a reed plant (Phragmites australis) or a cane, as in sugar cane. The man in my photograph had gathered a pile of cañas from a nearby torrente to use in his allotment garden to train his tomatoes, runner beans or whatever legume he was planning to grow. Before sticking the canes into the ground, he meticulously and lovingly peeled the skin of the cane sticks with a hoz (sickle type tool) the way it might always have been done here in the Balearics.
The photo was taken in Pollença, Mallorca, Baleares, Spain. The date: May 27th, 2009. The time was 19:13:35.
The Mallorca Photo Blog 
Great photo and article as always. Where we are, a caña is the smallest beer, maybe 200ml. It’s normally the cheapest drink on the menu. A slightly larger beer is a tubo, around 300ml and certainly named after the shape of the glass (tall and tube shaped). And only the tourists ask for a cerveza grande … warm before you’ve finished!
Different inflections for different places. Another Canas, Alberto owns a winery in Spain. At one time our family owned a brewery and Canas was the brand , under My Grandmother Francis Canas and we have been involved in the distilling of alcohol on and off since mideveal times.
It would not surprise me if another Brewery was started in Spain.