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A free email agroforestry journal for practitioners, extension agents, researchers, professionals, students, and enthusiasts. One edition is sent each month focusing on a concept related to designing, developing, and learning more about trees and agroforestry systems. Focuses on trees and their roles in agriculture, natural ecosystems, human culture and economy.

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Overstory #185 - Trees for scenic quality management

Introduction

Agroforestry systems are fast becoming major features of Australian rural landscapes. Their type and placement in the landscape can significantly improve a farm or catchment's scenic value or, conversely, degrade it.

Often, scenic improvements can only be achieved if suitable landscape designing is integrated into the overall agroforestry planning process. Failure to do this may cause unacceptable levels of social, environmental and economic impact whilst reducing the potential multiple use value of agroforestry resources.

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Overstory #184 - Organic Farming

What is organic farming?

Organic farming works in harmony with nature rather than against it. This involves using techniques to achieve good crop yields without harming the natural environment or the people who live and work in it. The methods and materials that organic farmers use are summarised as follows:

To keep and build good soil structure and fertility

    • recycled and composted crop wastes and animal manures
    • the right soil cultivation at the right time
    • crop rotation
    • green manures and legumes
    • mulching on the soil surface

To control pests, diseases and weeds

    • careful planning and crop choice
    • the use of resistant crops
    • good cultivation practice
    • crop rotation
    • encouraging useful predators that eat pests
    • increasing genetic diversity
    • using natural pesticides

Organic farming also involves

    • careful use of water resources
    • good animal husbandry

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Overstory #183 - Forestry interventions to reduce poverty

Introduction

More than 25 percent of the world's population – an estimated 1.6 billion people – rely on forest resources for their livelihoods, and of these almost 1.2 billion live in extreme poverty (World Bank, 2001). These people lack the basic necessities to maintain a decent standard of living sufficient and nutritious food, adequate shelter, access to health services, energy sources, safe drinking-water, education and a healthy environment. When governments signed the Millennium Declaration in 2000 and committed themselves to achieving the Millennium Development Goals, they agreed to halve the number of people living in extreme poverty by 2015.

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Overstory #182 - Remember to touch trees

Introduction

Since 1998, Dr. Alex L. Shigo has contributed four articles to The Overstory (editions 68, 69, 70, and 132). Earlier this month, Dr. Shigo passed away at the age of 75. Dr. Shigo led a revolution in the way we think about arboriculture. The following is a selection of passages from Dr. Shigo's prolific writings. See "About the Author" below for a brief biography of Dr. Shigo and for information about purchasing his publications.

from Tree Basics (p. 4)

A brief overview of some unique features of trees

Trees are the tallest, most massive, longest-lived organisms ever to grow on earth.

Trees, like other plants, cannot move. However, trees, unlike other plants, are big, woody, and perennial, which means they are easy targets for constant wounding.

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Overstory #181 - Dispelling Misperceptions About Trees

Introduction

There are many misperceptions about trees and their care. Many of these have been passed from one generation to the next without critical evaluation. Each of the statements below is TRUE.

Injuries

Trees are very different from people.

People and other animals are able to heal by replacing or regenerating injured tissue. A laceration on your finger quickly heals, so that several weeks later, the injured area is hardly noticeable. Trees are unable to replace injured tissues. Instead, they form boundaries around it that seal the area from the rest of the tree. The wood within the area that has been sealed off can no longer supply the rest of the tree with stored food. Additional injuries seal off more wood, which further reduces the supply of available food. The tree can slowly starve in this manner from repeated injuries.

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Overstory #180 - Animal tractor systems

Introduction

When planned and managed properly, animals can be key components in sustainable farming systems, enhancing important cycles of nature such as nutrient cycling and balancing of insect populations. A well-designed system with animals can also greatly reduce the human labor required to care for the animals and to prepare and maintain crop areas.

Animal tractor systems are a sustainable, cost-effective, and humane way to integrate animals into an agricultural system. Although the term "tractor" can be confusing, animal tractor systems do not involve draft animals.

Animal tractors are shelter-pen systems where animals such as chickens, turkeys, geese, ducks, pigs, or goats become integral parts of agricultural environments. In animal tractor systems, the animals are managed for productivity of eggs, milk, or meat. At the same time, the scratching, pecking, tilling, and manure spreading behavior of animals is used to prepare, clean, or maintain planting areas.

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