posted 14 years ago
c4 plants use co2 more efficiently then other plants and because of it, need WAY less water, or co2 for that matter. Long ago the earth used to have much more co2 in the atmosphere. as it lowered different plants adapted different ways. In dry areas this issue was compounded, as plants need water to process co2 which over time thee was less of, and some plants became c4 plants.
about the mulch, my point was that it did everything mulch can do, but that wasnt all you needed. the mulch blocks evaporation, the soil itself is still the medium to hold the water, which yours doesnt, its not evaporating away, its draining away.
It sounds like if you build water retention in your soil, that corn should thrive if the local farmers are growing it unirrigated.
If you cant dig in mulch and composts etc... Im not sure what else you can do.... hire someone to do it perhaps? sounds like its a major issue for your site. Im not sure of another way around it except nice and deep raised beds or something, hugelkultur or something on top of the soil. all of which is heavy work to.... the good thing is though, is if you find a way to build its water holding capacity, and continue to mulch after that, you wont have to continually dig it in. So you only have to find a way to get that consistency to start it should be easy enough to keep....