I am seeing green shoots everywhere these days. But not in the places in which Wall Street's strident financial cheerleaders and Washington's happy economists are. I am seeing green shoots in the many cracks in the suburban neighborhood roads I now travel daily by bicycle.

Unlike the supposed financial green shoots, these green shoots are not propitious. It is mid-June and the cities which I traverse by bike do not seem to have the wherewithal to douse the weeds that are cracking their streets. I also ride across many lovely private parking lots that are breaking up like so many crumbled cookies with no one seeming to want to fix them. I am reminded of images from a History Channel series called "Life After People" which depict what the Los Angeles freeway system would look like just one year after the disappearance of people (surprisingly green!) and how it might appear one hundred years after people (like a nature preserve!).

The roads are, of course, crumbling. But this has long been the case in Michigan where the governor and legislature refused to do anything about it throughout the 1990s and the early part of this decade for fear of voter reaction to new taxes. (One can still today close one's eyes and know immediately whether one is on the Michigan or the Ontario side of the Canadian border just by how the car rides.)

Not surprisingly, in the face of the current financial crisis, our local colleges and universities are doing what they can to encourage green shoots of their own on their campuses, namely, deferring even more maintenance.

There are reports, of course, of dramatic declines in capital spending by industry as well, especially by the energy industry. This is a natural response to the financial downturn, and we won't know for some time whether capital spending will recover to previous levels. In the public sphere, however, in the United States there has been a chronic underinvestment in what would be called public capital goods, and it is now getting much worse as governments at all levels are forced to slash spending.

These then are the origins of my green shoots, and they constitute an ominous sign about the ability of the economy to renew itself in the face of financial collapse and energy stringency. Every modern economy has what in economic parlance is called capital stock. That is the stock of goods (buildings, machines, roads, vehicles, power plants, etc.), both public and private, that are used to produce the objects and services we expect and depend on. In order for an economy to grow its output, it must either make the capital stock more efficient or it must simply create more of it. This would include factories, but also ships and trucks to transport goods to and from those factories, and often more roads and ship channels to transport them on or through. But in order for our existing capital stock not to fall into disrepair, we must maintain it or replace it.

If and when we find ourselves unable to increase (or make more efficient) the capital stock and simultaneously maintain the existing stock, we will be at that point in time which the authors of "Limits to Growth" envisioned. We would no longer be able to attain economic growth because the maintenance and/or replacement demands of the existing capital stock overwhelm our resources and prevent us from accomplishing both maintenance and growth at the same time. Ugo Bardi provided an excellent explanation of this problem recently on "The Oil Drum: Europe," dubbing it peak capital.

That's what my green shoots are telling me. Let me repeat it again: We may be nearing the point where the existing capital stock including the public infrastructure has grown so large and our resources, both financial and physical, have become so tight that we can no longer both maintain and expand the capital stock simultaneously. This does not necessarily lead to a dramatic collapse so much as a grinding decline in productive capacity. Over time the economy has more and more difficulty extracting basic resources from the Earth, manufacturing objects from those resources, and transporting those objects to markets, all while maintaining the buildings related to these activities.

It may be too early to sound the alarm on the end of economic growth. But if this is not the moment when we've reached the limits to growth, it looks very much like a dress rehearsal. And, that means that opening night cannot be far away.