Livestock and Forages

Document Sample
Livestock and Forages Powered By Docstoc
					Livestock and Forages: Essentials of Organic Farming?

Andy Hammermeister – Organic Agriculture Centre of Canada

Many farmers and researchers believe that organic farms can only be sustainable if they
include perennial forages, such as a hay crop, livestock as part of the farm.

Including perennial forage as part of a crop rotation can be very beneficial. Most
importantly, forage crops build soil organic matter. In addition to becoming a source of
nutrients, this decaying plant material also improves soil structure. The soil can hold
more water, is better aerated, and is less likely to erode or compact. A perennial forage
crop also breaks the cycles of weeds, diseases and insect pests. If your farm does not
include livestock, however, perennial forages may seem to be a costly practice that
removes land from production for up to five years. In an organic system, selling hay
reduces sustainability by removing nutrients that would otherwise stay on the farm and be
used for cash crops. It can also be argued that the benefits of perennial forages can be
achieved through careful management of crop rotations. Diversifying the rotation and
growing fall-seeded and green manure crops are techniques commonly used to break pest
cycles and sustain soils.

Livestock are also considered by many to be critical for sustaining an organic farm.
Livestock not only diversify farm income but can utilize by-products of crop production.
The manure from livestock can be a valuable resource for managing soil fertility in an
organic system. The high availability of nutrients in manure, especially nitrogen and
phosphorus, makes it very valuable in the prairies. In eastern Canada, however, the land
base available for safely disposing of manure is smaller and nutrient loading may become
a problem. Different animals use different feeds on the farm and therefore may have
different roles. For example, ruminant animals, those that chew their cud such as sheep
and cattle, can make good use of forage. Mongastric animals, those that have only one
stomach such as chickens and pigs, are less effective at digesting forage and therefore
need more grain or other protein sources in their diet. The manure produced by these two
groups of animals can be quite different in nutrient content. Many farmers do not raise
livestock for many reasons. Can an organic farm be sustainable without livestock? Or are
they needed for cycling energy and nutrients on the farm?

The net benefit of perennial forages and livestock in an organic farming system is not
clear. To help answer this question, the Organic Agriculture Centre of Canada and the
University of Manitoba are partnering in organic farming systems research project. A
four year crop rotation experiment has been established in Manitoba and Nova Scotia in
2002. The project is designed to address questions related to the economic, agronomic,
and environmental benefits of including perennial forages and livestock on an organic
farm. The basic crop rotation under study is wheat, soybean, barley, potato. The effects of
one or two years of forage in the rotation are being tested by replacing soybean or
soybean and barley with a forage crop suitable for the study area. The forages are
underseeded in the prior crop. To examine the importance of livestock, composts made
from manure of either ruminant animals or monogastric animals are used as a nutrient
source in the crop rotations.

We will be monitoring the economics of these farming systems by keeping track of input
costs and economic return. We will also monitor weed populations, crop diseases and
pests and crop nutrition to examine the agronomic performance of each system.
Environmental sustainability will be measured mostly by studying indicators of soil
quality. Such indicators may include the kind and amount of organic matter in the soil
and the measures of the microorganisms and small animals in the soil. At the end of the
project we hope to have be able to make a clear recommendation about how important
perennial forages and livestock are in an organic system.

At this time we can share some of our preliminary results from our plots in Nova Scotia
in 2002. Firstly, we found that the plots that received no compost (alfalfa meal was used
as a nitrogen source) were delayed in their early development compared with plots
receiving compost. This delay in development seemed to result in a slightly lower crop
yield and kernel weight. Interestingly, we also found that the number of weeds in a plot
did not affect yield. What was more important was the size of weeds and their total

For more information about this research please contact:
Andy Hammermeister
Organic Agriculture Centre of Canada
P.O. Box 550
Truro NS B2N 5E3
Ph: 902-893-8037