Bushes, Trees and Plants

So we were out for a walk this evening - off to Felony Park as I like to call it (that's another story). As we were walking along, I was pointing out the flowers, the dogs, the birds, the trees. Suddenly it hit me, Jude is going to have to learn the difference between trees, bushes, shrubs, hedges, plants - what the heck?!!? Who teaches children these things? Am I expected to try to explain the difference to him? This parenting thing is not for pansies! (Now a pansy is a flower, it's different from a daisy or a rose, I'm not sure how to explain it, but trust me, they are different - I should know, I've had a child!)