Published silhouette pics are misleading because they give an impression of uniformity within a species. Why not teach yourself, by using your twig guide to identify a species and then looking back at the tree from several distances? This will familiarize you with bark characters at the same time.
You'll learn a lot more that way and you won't be dependent on art work which is often lousy.

This question made me think of a related set of questions. There are programs on the web that try to identify the tree by asking a series of questions. Does anyone know what these are called? I've seen a name for them but cannot remember what it was. Also, does anyone know of a good one? The ones I have played with all seem to be very limited and very inflexible.

Myrtle, where did you get your twig guide? If it's a book, what's the name? How useful have you found it? Besides the twig characteristics, what else does it cover (bark, etc.)?

Brandon, the 'programs' that you are referring to are called "keys" and they are a classic method of plant identification based on morphological characteristics. I've linked to one very rudimetary online form but the better ones are more detailed and are published in the traditional manner. Personally, I find the online keys a bit awkward to work with.

Myrtle, the same link will get you to a winter ID guide for deciduous native trees. Again, the online form of this type of info is not as satisfactory as a book, IMO. And while various genera and species do not always grow in a uniform manner (too many variables for that to happen), you can ceratinly use winter silhouettes to supplement other known characteristics to narrow down your choices.

Here is a link that might be useful: tree key

I have had and used "Woody Plants in Winter" Core and Ammons for many years. C 1958. It's a comprehensive key for trees of NE US and SE Canada. It has bud, leaf, fruit and twig illustrations but does not talk much about shape or branching pattern. I have an old Peterson guide that has illustrations and is organized by genera. I found a pocket guide to winter trees on Amazon, that says it has branching patterns. I might try that.

i guess you are right, I would learn more by making my own. I was hoping to do some tree iding from the car during inclement weather.

While far from comprehensive, it is a good pocket guide (literally) for $3.50 at amazon: Winter Tree Finder by Mary T. Watts and Tom Watts. Like I suspect most winter guides, it keys mainly on the twigs.

FataMorgana