To clarify, I know biochar is good stuff, but I'm looking for people who have either used it themselves, seen it used, or have an opinion as to how worthwhile it is in practical applications. What I'm considering is not cheap, but if it works is well worth the cost.

I have used biochar. It is essentially wood that has been burned slowly with minimal oxygen, so instead of producing gray ash (which is mostly calcium carbonate, potash and potassium), it burns to black, dense, carbon-heavy charcoal.

There is a similarity here to the product produced at the end of the composting process - humus. Both humus and biochar are almost all carbon. In biochar the other elements have been released into the atmosphere during burning, and with humus they have been consumed by bacteria and fungus over the course of many years. And they both look similar - black and granular, like used coffee grounds.

They also both have the same function in the soil - the carbon holds on to nutrients and prevents them from washing down in to the water table, and in this way makes them available to the roots of plants near the surface. The don't add NPK and trace elements themselves, but they are a critical component of topsoil that allows plants to flourish.

Humus takes many years to form. What we normally call "compost" is material that has been broken down by bacteria, but fungi are still working on consuming the woodier portions of the plants. While bacteria work fast - their part of the process takes a year or so or even just months if you can get it hot enough - fungi cannot be hurried. Depending on how woody the original material was, they could take 10 years to completely turn leaves and sticks into moist black humus.

This is where biochar has an advantage. Rather than wait a decade for completely decomposed organic matter, you can burn wood either in the ground or in special ovens deprived of oxygen, and produce biochar in a matter of weeks. But, you pay for speed - biochar is relatively expensive, while every tree that falls in the forest turns in to humus for free - eventually.

But, to finish here, let's back up to the bigger picture. You lost your topsoil, so what you want to do is essentially recreate it. Biochar will help, but if we are talking about a whole pasture, that is an expensive proposition. An alternative that will take longer, but be much less expensive would be to get chipped wood mulch from tree trimming services for free and spread that on the pasture with some N fertilizer to speed up the bacterial decomposition process. That will eventually produce humus in the natural course of things and should be broken down enough to plant grasses next year.

I mostly agree with what richardbrennan wrote above, but some (perhaps too many) questions: you say 'fields', is this for commercial operations? How big an area are we talking about? Do you have more information on what the soil tests said (esp, for example, are the levels of other nutrients too high or just normal)? Have you done simple hand soil tests and what are those like? Do you see earthworms and the like? Have you been adding nitrogen in chemical form, what other soil amendments have been added? Do soil tests say what the organic content is?

Internet diagnosis means just a guess, but sounds most like that the soil has few of the organic components of regular topsoil, and relatively poor soil 'life.' What's in the soil now may be more or less biologically available to whatever it is you're trying to plant.

In those circumstances, before going the expensive route of biochar, it likely is worth trying the usual bulk soil amendment routes: woodchips, manure, compost (whatever available incl eg leaves), etc. Combined with mixed cover crops/'green manures' - range of possibilities depending on climate like buckwheat; nitrogen-fixing plants like alfalfa, clover, lupins; or white mustards or the tillage radishes. Note that part of the point of these is to let the root systems of whatever you plant start to do some of the work of giving some structure/biological life to what is likely a mostly mineral soil now.

If you really want to try the biochar, perhaps experiment and carve out an area within your fields and try biochar there, compare results. My thought would be that biochar may provide a decent amendment for stuff to grow in the soil, but on its own is not adding much in the way of soil life (the fungi, bacteria and other microbes) that manure and woodchips and compost and mixed cover crops would bring along with them. Also a question of how you'd incorporate the biochar, I believe most recommendations are to bury it somewhat, which is a big physical operation. "Applying" manure and woodchips about as simple as spreading on top (although could be tilled in), planting/spreading cover crops and letting biology and time take care of the rest.

Richard thank you for taking the time to reply. Just for a little clarity, these are pastures used mainly for sport horses, but some years we include a few beef cattle. I base my feeding program on grass, so better grass reduces the need to spend money on grains and hay to supplement that. Right now I have a huge animal to acre ratio so can manage, but I'd like to eventually run a bigger operation and the grass isn't good enough to handle increase wear and use. I have the land but not the grass.

I have a mix of grass with mostly grow fescue, although I have to over seed every few years. I also spend an inordinate amount of time trying to deal with bad grasses such as foxtail in the late summer. The foxtail tends to grow in the worst soil and if I could get a better stand of grass I could choke it out with a lot less labor.

All that is to say spending money for better soil can be a smart financial move for me--it's not just about a pretty lawn.

I have been spreading stall leavings--10 cubit feet of pine shavings plus at least that amount of manure and urine weekly-- back on the fields for 10 years now, concentrating in areas with the worst soil. I've had only a very little improvement in that amount of time. I have soil tested these areas separately over the years and they come back no different than the better areas: "Needs only nitrogen" which we regularly apply. Obviously this is not a NKP problem as much as it is figuring out what nutrient availability issues I have.

I'm curious if you have other reasons other than expense to suggest a slower alternate plan? Right now I'm looking to experiment with a few acres at about $125 applied--which is mostly product as I can do the application myself since I have the equipment. If it works--the big question--it's money well spent. I know it all sound good theoretically, but what results did you see when you used it?