untouched "by"?

Over the past three decades, Oregon has earned a reputation for having the most restrictive land-use rules in the nation. Housing was grouped in and near the cities, while vast parcels of farmland and forests were untouched by so much as[b] a suburban cul-de-sac.

This paragraph is an excerpt from an article in NewYork Times which you may access by clicking here:http://www.nytimes.com/2004/11/26/na...rint&position=

Would you please kindly tell me the function of "by" here as underlined and in bold? Thanks a lot.

[Casiopea]

It's a preposition, and it introduces the logical subject of a passive sentence:

Passive
...were untouched by a cul-de-sac.

Active
A cul-de-sac did not touch ....

Thanks for your reply Casiopea, but I can't agree with you.

...were untouched by so much (to such a degree that they can be considered) as a cul-de-sac.

Above is my understanding and originally, I was wondering if "by" here was a must-have because I think the sentence is still complete without "by" here.

I don't quite understand your meaning of "A cul-de-sac did not touch...". "A cul-de-sac" means a dead-end lane, right? In my opinion, the author wanted to say that the "vast parcels of farmland and forests" were not accessible, or not allowed to be developed, just as one couldn't get through "a suburban cul-de-sac".

Looking forward to your further explanation. Thanks

[Casiopea]

It's a passive sentence. The logical subject is 'so much as a suburban cul-de-sac', and it's introduced by 'by'. Try looking at it from this angle:

Passive
Farmlands and forests (structural subject)
were not even touched (Passive verb phrase)
by so much as a suburban cul-de-sac. (logical subject)

Active
Not so much as a suburban cul-de-sac (Logical subject)
touched (Active verb)
the farmland and forests (Object of the verb)

Now it makes sense to me. :) Thank you so much, Casiopea...

[Casiopea]

Originally Posted by chinawangyong

Now it makes sense to me. :) Thank you so much, Casiopea...

Great.