John, when I first started growing raspberries, I remember someone saying "you wont get any fruit in the first year, as they fruit on 2nd year canes".
When that second year came around, I got a fair daffy of fruits but then I began to wonder how was I gonna tell the difference between first year canes and second year canes?
Well watching them grow, I noticed the older canes became brown, but the new canes stayed green, so this became a rule of thumb from then on and I remembered to cut out the brown canes and leave the green ones to flower and fruit for the following year. simples ;-)