One good way is to get a detailed soil test done. Some places have specific deficiencies or imbalances. Advanced testing usually asks what your goals are, and building organic matter is an option.
Regional areas with known issues may have specific tests they looking for.
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Disturbing it can be a good way to loosing it too, erosion.
Cover crops not only increase oganic matter, but they're used more to prevent erosion and nutrient loss.
Certain nutrients are held up in plant material while they decay, which can take a few months or even a few years. This is why rotating crops is important.
In areas by me, improving drainage and dealing with compaction / hardpan is one of the lines in the sand between average and more successful farmers. The use of a subsoiler can help alot.
Farmers deal with profit first though. Certain years crops appear to be more valuable than others. Risk has been a factor to some here n NY. Wet springs has wrecked a few corn crops.
One more recent improvement has been the use of chaff spreaders. The unharvested portion of the plant, that is chopped up and spit out of the harvester is called chaff. It used to be dumped out the back. Some combines have a spreader to distribute the leftovers evenly. Folks who use brush hogs on food plots often travel too fast or use not enough pto speed to evenly spread the grass.
Many food plots I have seen over the years usually lack enough southern light. Simple fix with a chainsaw.
What's your goals? Good soil health doesn't always agree with high deer attraction at the time you want it.