The world health really means wholeness. You know when you're whole. You also know, when some one owes you a debt, what it means to be "made whole." You also know what it means to feel sick. Whenever we're sick, we're not quite healthy, which means something's just "off." That lack of health is a lack of wholeness. When we approach a farm holistically, we should think of it as a living organism, as a living whole, as a totality and not just a bunch of parts.
Though not a term available to Rudolf Steiner at the initiation of biodynamics, the word "holism" was born in South Africa contemporaneously.
South African Jan Christian Smuts coined the term "holism" in his seminal work Holism and Evolution (1926) against materialism and reductionism but his name is relatively unknown today.
Even a mechanic talks in terms of wholes. Yes, your auto mechanic might be working on your carburetor, but he'd say he's working on a specific car -- the blue Ford F150. You know when your automobile is working and when it isn't. In fact, we learn most about our machines (and our bodies) when they aren't working! When things are going smoothly, we don't feel too much motivation to break out the owner's manual, do we?
On the farm, we should imagine the farm as if it's a living thing that can be healthy or unhealthy and watch for where there's stagnation or inflammation. Look out at the field and you'll see dry spots or water-logged areas. Imagine that in your body as arthritis or bloating and you'll quickly grow more sensitive to how the farm organism "feels" and how to make it healthier. If there's excessive dryness on a spot, perhaps it needs shade. If there's excessive water in one area, perhaps it needs a willow to evaporate the stagnant water. Ehrenfried Pfeiffer reports that a single full grown Salix Spp. willow tree can evaporate 5000 gallons of water per day.