Read our collection of articles about sustainable agriculture:
The food chain is often described as a pyramid – or, more
precisely, a “biotic pyramid”.
Soil forms the base of the pyramid, plants are on the lower
level, then plant-eating animals (herbivores), with
animal-eating animals (carnivores) on the top level. If
humans are included, they are placed at the very top.
The pyramid design shows very clearly that there are many
species and individuals at the lower levels, and fewer at
the higher levels of the food chain. The reason is that from
one level to the...
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Most of us are astounded to discover just how extensive and
complex the plumbing system in plants is. Not only do plants
take up water and nutrients through their roots, but also
through their above-ground upholstery – their leaves.
Plants can take minerals from the air in the form of dust
particles and floating ions. Indeed, some scientists believe
the air contains all the nutrients plants need. A year’s
rain delivers ample supplies of nitrogen, phosphorus and
calcium, and these can be absorbed directly through the waxy
cuticle that...
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Plants are a lot like people really. They just love
stretching out and soaking up sun and moisture.
True, plants are different organisms from us and the animals
we’re familiar with. Plants do not have eyes or ears,
bones, nerves or muscles. They can’t walk or run around
from place to place.
But, just like us and animals, plants are sensitive to light
and vibrations. They have a supporting skeleton, they
display electrical activities, and they do a considerable
amount of moving. They are living, breathing organisms.
In fact, a...
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Soil is the absolute basis of agriculture – and,
therefore, of human existence. We survive by eating plants
grown in the soil, or by eating animals that eat plants
grown in the soil.
Quite clearly, soil is our most important national resource.
Wise use and management of the relatively thin upper layer,
the topsoil, is crucial for us to maintain good health and a
high standard of living.
But, because of misuse, a frightening large amount of
topsoil is lost to erosion – well over 30 tonnes per
hectare in...
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Before we tackle a problem, it’s often best to step back
and look at the bigger picture. If we can understand the
whole issue – its symptoms, causes and possible solutions
– we’re usually better placed than if we concentrate
solely on the problem.
Agriculture works with things of nature…… with natural
systems, with living biological species of plants and
animals, with the natural environment. Nature, of course, is
incredibly complex – even a tiny cell is more complex than
any man-made machine.
The study of the way in which...
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Animals need food for two reasons – to produce energy; and
to build new cells and grow, reproduce, repair injury, and
produce milk or eggs.
Animals normally use carbohydrates and fats as “fuels”,
although proteins can also be used for this purpose in times
of starvation or excess. As far as growth is concerned, the
essentials are proteins and minerals (calcium and phosphorus
for bones and teeth, iron in the blood, sulphur in some
amino acids).
But the cellular metabolic activities of both energy
production (catabolism) and growth (anabolism) also...
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pH is a soil condition you hear about a lot from "experts"
– excessively so, in fact. Nevertheless, pH is important,
and we should not ignore what it is telling us.
pH measures soil acidity and alkalinity. And, as soils
become more acid, grasses and clover do not grow as well.
Which reflects why pH levels provoke so much interest in New
Zealand’s grass-based agricultural system?
The acidity or alkalinity of any substance is defined by pH
using a scale of numbers from 0 (most acid) to 14...
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Remember the old line about what happens to composers when
they die. They decompose. Well, forget all that when it
comes to dead organic matter and the soil. Because quite the
opposite occurs.
Dead organic matter – in the form of the dead bodies of
plants and animals, plus the waste excretions of animals –
is broken down and returned to the soil so that the
nutrients it contains can be reused by plants.
Today’s environmentalists call it recycling. But Nature
has been on to this secret since the...
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Nearly all of us are familiar with composting. For many of
us, it’s going on in our backyard everyday. Like rust, it
never sleeps.
But composting – the practice of letting organic matter
rot before you apply it to the soil – is more than merely
a backyard hobby. It’s a direct application of microbial
decomposition to agriculture, and is particularly favoured
by followers of organic farming methods and, of course, by
many gardeners.
It’s quite simple really. You just let organic matter rot
before you put it on the...
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Flower buds and flowers are prerequisites to the production
of seeds or fruit by plants.
Tiny flower buds are actually formed long before they become
obvious. In corn, for example, the cob and tassel buds form
when the plant is only about knee high. In apple trees, the
buds that will produce next year are formed this year.
The quantity and quality of fruit and seeds depends partly
on the number and health of the flower buds – along with
other factors such as weather, light, nutrients and
pollination....
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