My definition of sustainable is quite textbook:

of, relating to, or being a method of harvesting or using a resource so that the resource is not depleted or permanently damaged

Some in the sustainable ag community feel that herbicides, insecticides and fungicides cause a poisoning of the soil and water that creates permanent damage. I'm not in that group, but I also don't rule it out and I keep my ears open for evidence to the contrary.

Some in the sustainable ag community feel that fossil fuels are a requirement for the economically efficient production agriculture that we are currently blessed with. They also feel that this form of agriculture is not very resource efficient. I am in this camp and I do not know what to do about it. I also don't know if it will be a problem 50 years from now or 5000 years from now. I believe we have a finite fossil fuel supply, but I don't know how to quantify it and I don't think anyone does. I hope that we find a different form of energy before it becomes a major problem.

Some in the sustainable ag community feel that fertilizer is a finite resource and when it's gone, we're in trouble. I would imagine that any resource on this planet is finite so I don't see any reason to disagree. Same as fossil fuels though, I don't know how to quantify it and I don't know that anyone does.

I think that the best way I've heard it explained is that we have become exceedingly efficient from an economic standpoint but we aren't very efficient at all from a resource standpoint.

I am not advocating we all go and live off a garden. In fact, to that I say, you first. On our farm we make extensive use of herbicides, insecticides, fungicides, fertilizer and modified seed. I am saying that if we do someday deplete the resources we have available to us, the world population is going to drastically shrink. I am also saying there is nothing wrong with self-analysis to determine whether one could be more resource efficient without hurting economic efficiency.

I will not scoff at the term sustainable agriculture. I hope to find time to experiment on our farm with methods that are more sustainable from a resource conservation perspective than what we currently do. I enjoy reading about people like Gabe Brown who has found some rather unique ways to make production agriculture work.

So there you have my definition of sustainable. There are probably some similarities and some differences between my definition and that of an "environmentalist". As a farmer though, I believe it is my responsibility to be a good steward of the resources I've been entrusted with. Shrugging of the potential of my current practices being unsustainable is not consistent with upholding that responsibility.