Dear Allan - David - Michelle wrote > > I hadn't even considered that I was depleting the soil > >doing this. I guess that I struggle with that concept. (that grazing green crops is detrimental - me too)
In my kind of rainfall environment it takes a season to grow a bulky green manure crop, if we then plow it in we need to use a disk implement of some sort to get the job done, so we get caught in the classic overcultivation trap and by the time we plant crop our organic carbon reading has gone way down - the disking overstimulates the system and we get excessive mineralisation over summer - burning up accumulated carbon as well as the green manure crop - but if we graze these paddocks down in spring we can then use a tyned implement to cultivate (chisel plow is best for us) and we get much less rapid breakdown over summer so although we put less vegetable material into the system to start, we end up with better organic carbon at seeding time and we have more available for release of organic nitrogen as the crop grows. Its a more balanced result. Michelle is working to a different time frame, It takes a massive amount of biological activity, warmth, lots of moisture and energy, to break down mature crop residues quickly without throwing the soil system out of balance (nitrogen deficit) . All of those things are going on in a ruminant animal all the time, we use sheep but cows are better at bulky stuff. I think its pointless trying to build up soil levels (carbon and minerals) if we then have to burn it back down with cultivation to prepare for the next crop. Balance is the key ! Maximum of anything is not always the way to go! Cheers all Lloyd Charles
