During the decade when I was born in Saratoga, CA there were only 470 homes built. Most of the surrounding land was in orchards. During the 1950’s the boom started, reaching its peak during the 1960’s. The 1970’s were also active home building years, but it tapered off dramatically after that as most of the large parcels were converted to subdivisions.
As a result of age, most areas have big beautiful street trees, but it also means that the land is more valuable than many of the older house structures. As a result, many homes are either being remodeled or torn down and replaced with much larger homes (particularly were there is estate acreage).