not sure where this debate is heading it certainly seems to be getting somewhat personal, not a good debating method to attack anyone's character, we don't know each other that well enough. a judgement can't be made unless one knows about who they are judging. this whole spent mushroom compost seems to be getting off line, see our bale garden presentation like all gardens we do they are raised and like all gardens to date, we use spent mushroom compost in the beginning and when topping up is needed we use spent mush' compost again. it's not so much about improving the soil that is there but it does that very well from our experience, i'm not sure about the gypsum factor in the mush' compost? but either way we end up with a good growing medium, that we plant in as soon as the garden is built, we have the pic's there unless someone is going to judge that we are slight of hand and snake oil sellers? all the soils we get to work with here are clay and we use heaps of gypsum sometimes a sprinkle of dolomite as well but rarely, at around 12 months or more we dig by finger through our medium and down into the original soil without really noticing so some change for the better is occurring. i listen rarely to science they only get involved when someone pays them to so they support the persons who pay them, in gardening KISS is the go, science has led our food growers down the wrong path and over here with their nothing but theories they are conspiring on this climate change do dat. len Here is a link that might be useful: lens straw bale garden

Well, the original poster does pose an interesting, if completely hypothetical (viewed in light of current financial and political realities), question. However, the correct answer is "no tree!" Why? Well, because any attempt to establish any sort of outpost of any kind on Mars or other extraterrestrial venues would require plant material which would have a tremendous capacity for growth, and trees are much, much too slow. In fact, I suspect that the main type of plant material which would be used on the first few missions of this type would probably be certain kinds of green algaes, which would grow quickly on the waste nutrients (sewage and garbage) generated by the crew and any animals with them, purify the environment, produce oxygen, replicate themselves extremely rapidly and produce a tremendous amount of biomass that could be recycled into food or fuel. There are certain algaes that definitely fit that description. Long range, I suppose that trees and other higher vascular plants could be used to provide food, oxygen, fuel, purification of water, etc., in extraterrestrial colonies, and even possibly be used to terraform an alien world like Mars, as was suggested by Carl Sagan and others many years ago. I still think, though, that trees would be among the LAST to go, since they take SO long to grow compared to other plants. Things with the growth rate of water hyacinths, certain grasses, amaranth, etc., are more likely candidates.

Love the shot of picking tomatoes with a cherry picker. You sure got the right combination of amendments to have such a successful crop. Thanks for posting the pics.

I saw this movie yesterday. I did enjoy it. And as gardeners there were few scenes we would (especially) appreciate. Who has seen it?