Selecting a few different subject areas is a good way to both train your eye and develop photographic skills and techniques. It also provide a good back up if the weather is not so good or the area you are in has limited photographic interest. There are many different subject you could focus in on, and its a good idea to choose something that has a mix of colours, textures, shape detail and composition qualities.
I have chosen trees in this example as there are numerous examples in and around the parks and gardens of London. My favorite ones are in Hampstead Heath, Kew Gardens and Greenwich and Richmond Park. For me, the main problems in taking these shots for are getting the lighting right and isolating the tree so that it stands out.
Photos © Philip Carey 2010