Sentence Diagrams

I’ve been thinking about sentence diagramming. Both this kind:
(which has gotten some recent press with the release of this poster)

and this kind
Or a more complex version of this linguistically-informed syntax tree, such as this:

Dick Hudson discussed a bit about the history of diagramming recently here and Beth Keyser has been using linguisticky (Like that spelling? And how would you spell the present participial form (-ing) of the verb picnic? We are picnic___. Sometimes our spelling system fails us, but we make do.) trees in her classes for several years; she and I will report on this soon. I’m also planning to write up a more thorough investigation (an article rather than a blog post) of the pros and cons of various kinds of visual representations for sentence diagrams, but in the meantime, these are some musings and some questions.

There were various studies in the 1930s and 1940s about whether sentence diagramming improved student writing. Mostly it didn’t seem to (though the methods of evaluating improved writing were and are messy). But what else can creating and using visual representations of sentences do for us? Certainly, whatever kind of diagram is used, one must know the categories of each word and of each phrase and be able to show how all of those fit together to make clauses. Throughout this blog, there is a presumption that such knowledge of categories, phrases, and clauses is useful. I have emphasized that we have such knowledge unconsciously, so what are the benefits of making it conscious knowledge? Even those who say that in middle and high school you should just teach grammar in context (such as Constance Weaver), and suggest teaching the bare minimum, all include some very basic grammatical information that students should recognize and be able to discuss. These include the basic parts of speech, subject and predicate, and clauses and phrases. Well, that’s a lot, actually. And can using diagramming of one kind or another help with that? Or does it introduce an unnecessary complication? My college students who are planning to become teachers say and write over and over that one of the most important things they learn in my classes that they hope to introduce to their future students is using visual representations - tree diagrams - to help elucidate the structure of sentences. What do you think?