Seven years lead time?

In the news...assertions that it will be seven years before oil production could be expected from any new drilling. Drive-time thinking as I return from a necessary and very important long journey. On the right of the highway, orderly rows of Christmas trees climb a hillside; perhaps they were planted seven years ago. I think of the first seven years of our children's lives when we invested all we could into their nurture and readiness for life-long learning and for "school". Seven years post-secondary study may earn a doctorate in medicine or law or ministry or....In seven years our next United States President could be winding-down a second term. Hopefully the new paint on our house will still look good in seven years. Seven years(?) figures importantly in the Bible's books Daniel and Revelation. Perhaps it was seven years ago that the well was begun which produced the fuel that takes me home today. Let us not neglect conservation and stewardship of earth, neither let us put off drilling for oil and developing other technologies toward energy independence for ourselves and future generations.