If you think identifying little brown birds is difficult, there are far more taxing issues! And once you have sorted out common milkwort from chalk milkwort have a go at crane flies ... Tipula oleracea has 13 segments in its antennae and Tipula paludosa has 14! Otherwise they are 'very alike'.
The thing is, though, that physical features are not the only guide to identification and we often forget that. Tipula oleracea is around between April and October and Tipula paludosa from, errr, April to October. However, Tipula oleracea is abundant in May and June whereas Tipula paludosa is abundant in the autumn. As a result, as I photographed this one in May I can be fairly certain that this is Tipula oleracea and not Tipula paludosa even though I cannot clearly see the number of segments in the antennae. If anyone wishes to query my judgement then go ahead but be sure of your facts!
Actually, Tipula oleracea is slightly bigger than its cousin because the wings are the same length as the body, in Tipula paludosa the wings are shorter than the body. This is not always obvious in the field but in my photograph you can see the wings are the same length as the body even though they are outstretched so Tipula oleracea it is.