Agriculture Reference
In-Depth Information
Air
Plants are over 50% air. They're over 40% carbon, most of which comes directly from
the air, and over 40% oxygen, which comes from the air and from water. They're 1-4% ni-
trogen, which originates in the air. While some plants are pollinated by birds, insects and
other animals, all conifers and grasses and many deciduous trees rely on wind for pollina-
tion. That's how they mate. Many plants also use the wind to spread seed.
The air in most North American gardens contains pollutants that have traveled across the
ocean from Asia. Pesticide spray can come into your garden from 50 miles away. Acid rain
— caused largely by us through our vehicles, factories, electricity generation plants, and
meat production — is causing environmental problems around the world.
As organic gardeners, air is important to us, but we admittedly don't think much about it
because we don't have control over it. Sure, we can drive less, fly less, and use less power
in general. We can eat less meat and not burn toxic things. But is there anything we can do
in the garden? To start, it makes sense to think about air circulation across your property
when you're designing your garden, and place plants and structures in a manner that allows
for air movement.
Our friends in the soil need air, too. Most of the helpful bacteria and fungi are aerobic.
They need air just like us. So do plant roots. A healthy soil is made up of approximately
25% air. This is not achieved long-term by rototilling or aerating the soil. In fact, that can
destroy the soil structure if you do it too often without incorporating organic matter. Proper
air in the soil is achieved not by us, but by the hard work of the microorganisms, insects
and earthworms building themselves cities. Our only job is giving them the tools they need
to do this.
