Only for those convinced they need to replenish something in their soil that probably does not need replenishing if that soil is p[roperly cared for. Since the level of Phosphorus in my soil went from Low Optimum to High Optimum over the years, without my adding any thing other than compost, and has stayed there for many years with a humus level in the soil of about 8 percent, I doubt that the need really exists to spend money on Rock Phosphate, or any other form of Phosphorus.

Yah, I'm not saying you should rush out and start stockpiling phosphorus. It will be a problem long after we are all in the ground. I just found it fascinating that such a critical resource (required for energy transfer in plant and animal life) is not only very finite, but so concentrated in one country. Just makes me think the P mines of the fairly obscure country of Morroco will someday be to the world what the oil fields of the Middle East are today. Derivatives of phosphate rock are commonly used as P fertilizers for grain and hay production, which are subsequently fed to livestock and poultry, which produce the manure that many of us use in our compost. So ultimately much of the P in that manure comes from the phosphate rock.

Part of it has to be simple economics and lesser or lower-grade deposits must exist at locations harder to ship from. It is like an observation I once read (on paper) from an industrial technology commenter noting how iron could be extracted if needed from many of the world's enormous store of reddish residual soils. We are in no danger of running out, just in running out of the easy stuff.

(Also, I have to laugh. Apparently a vast, incredibly expensive and profitable international market involving millions of tons dug, processed, and shipped is all basically unneeded and could be replaced by simple advice from the organic gardeners.)

P is in poo. Lotta people is a lotta poo is a lotta P.

No doubt. We need to do a better job of recycling the P in that poo. The P in the poo comes from the food that was eaten, most of which was grown using P fertilizers derived from phosphate rock. I think it is a distribution issue also. If you have high P in your soil, and you continue to add large amounts of P (as fertilizer, or organic amendments) are you overusing a finite resource that should be distributed to a location that needs it?

P is just the tip of the iceberg:

Here is a link that might be useful: strategic minerals

It's not about the home gardener, it's about the price of food when millions of tons of this stuff are used in row crop fertilizers.

Yeah, poo is definitely the untapped resource. We need to get the toxins out of the sewage so the nutrients are safe to use.

The great SF writer Isaac Asimov did an essay once on P as the 'limiting reagent' of the biosphere.

I'm so glad to hear that you like Asmiov there Tox.
I just gave my son his first copy of I Robot.
(sheds a little happy tear)
Okay, I'm done thread jacking now.

Always an SF fan. My high school chemistry teacher had us read his 1975 book "On Chemistry" which is where I saw the phosphorus essay. The teacher and the book were two things that influenced me to go into chemistry.

One testament to his greatness as a scientist and interpretor of technical topics for the masses: Asimov was invited to give a speech to a womens' group on how the human female could be improved, scientifically and biologically speaking. The result was thoughtful, interesting and humorous. He suggested self-regulating internal birth control, which he thought would be quite freeing. As well as moving the breasts to the back to make dancing more fun for the partners. Truly a great mind, that one.

"The teacher and the book were two things that influenced me to go into chemistry."

View From a Height is what first got me really excited about science back in high school.

Actually iron is probably more of a limiting agent, but it in the oceans (2/3rds of earth).

My trigger for chemistry and science in general was a wayward middle-school youth's preoccupation with fireworks and the milder explosives. It is a story quite common with professional chemists and some other scientists. I know of none who truly went bad with it. All became respectable citizens.

I slept through school.

I volunteered to help in the chemistry lab helping prepare reagents for class. One day the teacher said he thought I was looking pretty closely at the shelves of chemicals. I jokingly said "When can I start building a bomb?" He laughed and then made it quite clear it would be the end of my career one way or the other if I tried.

My definition of 'volunteer' is the person who did not understand the question.

:-)

Lloyd

My definition of 'volunteer' is the person who did not understand the question.
Ha ha ha. That's a great line.

Sometimes the volunteer is the guy (or gal) that didn't show up for the meeting...hard to say "not me", if your not there!

Where you see burdock you see adequate levels of iron and phosphate. Not enough calcium.

OK, thanks for that pnbrown...I think. [scratches head] haha :-]

We have a lady here in the office who has a talent for wandering into a conversation and contributing distantly related but generally not applicable facts to the discussion, just out of the blue. Her name's Vicky, so we call her Vickipedia.