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ECHO Tech Notes are subject-specific publications about topics important to those working in the tropics and subtropics. Our material is authored by ECHO staff and outside writers, all with experience and knowledge of their subject. These documents are free for your use and will hopefully serve a valuable role in your working library of resources in agricultural development!

93 Issues in this Publication (Showing issues 24 - 15) |

TN #24 Onions in the Tropics and Subtropics - 1992-01-01

A case could be made that onions are one of two universal vegetables that are cherished in almost every culture, tomatoes being the other. Both are difficult to grow in many tropical and subtropical climates. Where a vegetable is both popular and difficult to grow, it brings a good price. If a way can be found to grow that crop, both local farmers and consumers benefit. While attending a horticulture conference in Honduras, Scott Sherman and I had an opportunity to visit with onion specialist and international consultant, Dr. Lesley Currah. She travels the world working with onion researchers.

Cite this article as:

Price, M.L. 1992. Onions in the Tropics and Subtropics. ECHO Technical Note no. 24.

TN #23 Living Fence - 1991-01-01

There are several reasons for establishing fences on the small farm. Fences are used to:

  1. To mark boundary lines between farms or next to roads.
  2. To separate adjacent fields used for distinct purposes
  3. To protect and keep animals from straying
  4. To protect crops from animal damage

A fence represents a major investment on the small farm. Although it carries a cost, it also provides something of benefit, namely protection. It is often a challenge to small farmers to increase farm production, such as crop yield, and the use of fences can facilitate such improvements. Whereas a fence may facilitate yield increase on the farm, a living fence can improve the efficiency of the production as well.

“Major” fences are usually constructed of poles and wire. “Minor” fences, such as those used for fencing small animals or kitchen gardens, may be constructed entirely of wood, or of a combination of materials, such as poles, slats, and woven or welded wire. Both major and minor fences may be constructed of living posts, reducing initial costs of the fence. Additionally, living posts last longer than wooden (dead) ones, thereby reducing maintenance costs as well.

Living fences are commonly used in a wide range of ecological situations, from semi-arid to rain forest conditions. Suitable plant materials are available for almost all ecological regions and conditions.

What’s Inside:

  • Benefits
  • Disadvantages
  • Establishment and Care
  • Species for Living Fences

Cite this article as:

Martin, F.W. 1991. Living Fence. ECHO Technical Note no. 23.

TN #22 Guinea Pigs for Meat Production - 1991-01-01

The high protein and high concentration of B vitamins found in meat make it an ideal part of the diet, very difficult to replace by plant foods, even with grain legumes that are nutritionally the closest plant foods to meat. Yet production of meat on the small farm almost dictates a way of life with several disadvantages. If small animals are raised in pens they usually require purchased concentrates or grains used for the family, at least as part of the diet. If allowed to roam freely they make it impossible to maintain a dooryard vegetable garden, and make good hygiene difficult. Furthermore, if the family cannot eat the entire animal at one meal, refrigeration is required or other preservation techniques.

The guinea pig or cavy, Cavia porcellus, is a rodent that was domesticated in the Andes as a source of meat. Because it is a small animal it can be eaten by a small family in one meal and does not require refrigeration. It is herbivorous and becomes accustomed to many sorts of feed. The meat is much like rabbit, and is low in fat content. Furthermore, the cavy multiplies rapidly, but not at the rate that folk literature would suggest. With breeding as recommended here, one pair of cavies could produce about 260 new pairs in 2 years.

Cite this article as:

Martin, F.W. 1991. Guinea Pigs for Meat Production. ECHO Technical Note no. 22.

TN #21 Pigeon Pea - 1990-01-01

I often tell folks that ECHO specializes in growing food under difficult conditions. The pigeon pea, Cajanus cajan, is a prime example of a tough but nutritious plant for just such cases. This article is directed toward two audiences. For some of you, pigeon pea is already an important crop. You will mainly be interested in the information about and seed of vegetable pigeon pea varieties. For others who are not familiar with pigeon pea at all, the general discussion of pigeon pea is for you. (The following information is gleaned from a very helpful book, Pigeon peas: a Valuable Crop of the Tropics, by Julia Morton, Roger Smith, A. Lugo-Lopez and R. Abrams, available from Dr. Eduardo Schroder for $7.00 at Dept. of Agronomy, University of Puerto Rico, Mayaguez, PR 00709-5000, USA.)

Cite this article as:

Price, M.L. 1990. Pigeon Pea. ECHO Technical Note no. 21.

TN #20 Selecting the Best Plants for the Tropical Subsistence Farm - 2007-01-01

By Dr. F. W. Martin. Published in parts, 1989 and 1994; Revised 1998 and 2007 by ECHO Staff

Though nearly all plants are useful in some way, they are not equally valuable. For example, wheat, rice and corn may be considered the most valuable plants in the world based on the vast acreage planted to these crops, their vital role in feeding humankind, and their enormous economic value. Using various criteria, one might consider 10, 25, or even 200 species as the world’s most valuable plants. Yet, under some situations, by some people, or for some special reason, other plants produced and used on a very small scale might be precious and indispensable. The question, “Which are the most valuable plants for the small farm?”, then, becomes breathtaking.

What’s Inside:

How to Find the Best Plants

Descriptions of Useful Plants

Cite this article as:

Martin, F.W., and ECHO Staff 2007. Selecting the Best Plants for the Tropical Subsistence Farm. ECHO Technical Note no. 20.

TN #19 Maize - 1989-01-01

Maize (Zea mays; corn) is the third most important food crop in the world, surpassed only by two other grains, wheat and rice. Maize is a widely adapted crop, capable of production during the appropriate season in almost all parts of the world where farming is done. Maize is represented by thousands of varieties, some producing in as little as 70 days, others needing up to 9 months to reach maturity. Furthermore, maize is represented by a number of distinct races that evolved in Mexico and Central and South America, its geographical origin. These groups hybridize freely.

Cite this article as:

Martin, F.W. 1989. Maize. ECHO Technical Note no. 19.

TN #18 Sweet Potato - 1988-01-19

Sweet potatoes (Ipomoea batatas) are already the 6th or 7th most produced food crop in the world, surpassed only by wheat, rice, corn, potato, barley, and possibly cassava. Among the reasons that sweet potato is a great crop is that it is relatively easy to grow, relatively free of pests and diseases, has relatively high productivity, and is always good food, principally starch, some protein and vitamin C, and, in orange varieties, rich in vitamin A. In addition, the young leaves, rich in protein and most vitamins, are also good food. Furthermore, the sweet potato is an excellent animal food.

Its ability to produce in poor soils makes the sweet potato an especially good crop for poor tropical soils where fertilizer is not available. If the leaves are also used as food, sweet potato will probably produce more nutrients per acre than almost any other crop under those conditions. (The other tropical crop that produces well on poor soils and also has both edible roots and leaves is cassava. It has an advantage over sweet potato in drought tolerance, but sweet potato has the advantage in nutrients. That is because substances called polyphenols in the cassava leaf combine with protein during cooking and reduce the amount of protein that is digestible.)

Nevertheless, like all crops the sweet potato must be produced with understanding in order to obtain maximum yields. It should never be treated with neglect.

What's Inside:


Cite this article as:

Martin, F.W. 1988. Sweet Potato. ECHO Technical Note no. 18.

TN #17 Soybean - 1988-04-01

The soybean (Glycine max) is one of the most important food plants of the world, and seems to be growing in importance. It is an annual crop, fairly easy to grow, that produces more protein and oil per unit of land than almost any other crop. It is a versatile food plant that, used in its various forms, is capable of supplying most nutrients. It can substitute for meat and to some extent for milk. It is a crop capable of reducing protein malnutrition. In addition, soybeans are a source of high value animal feed.

Nevertheless, the soybean is adapted primarily to the Temperate Zone. Each improved variety has an adaptation determined in large part by latitude. Soybean requires careful home processing to bring out its best qualities, and if not well prepared, it has an off-flavor that is seldom appreciated.

Cite this article as:

Martin, F.W. 1988. Soybean. ECHO Technical Note no. 17.

TN #16 A Beginners Guide to Small-Scale Tropical Agriculture

So you want to help people in the tropics.  Beautiful! The tropics are waiting for you. No matter what your abilities, you can make life better for others in the tropics. Your concern for the physical and spiritual well-being of people can be translated into fruitful service. Your first asset is your good will, your willingness to serve. 

As you begin to get acquainted with the tropics, you will find that common problems include production and the use of food. Among the poor, those that most need your help, obtaining one's daily bread is a constant concern. This is not only a question of eating. It is first a matter of production, second of distribution and storage, and third of preparation of meals and balancing the diet

What's Inside: 


Some Common Problems

Interaction of Agriculture and Human Welfare

Steps Toward Improving Small-Scale Tropical Agriculture


Cite this article as:

Martin, F.W. 1988. A Beginners Guide to Small-Scale Tropical Agriculture. ECHO Technical Note no. 16.

TN #15 Moringa Recipes - 1988-01-01

"Of all parts of the tree, it is the leaves that are most extensively used. The growing tips and young leaves are best. [However, we sometimes pull the leaflets off in our hands and cook them without regard to age]. Unlike other kinds of edible leaves, benzolive leaves do not become bitter as they grow older, only tougher. When you prepare the leaves, always remove them from the woody stems, which do not soften. [We did not know this the first time we served them. It was almost like having wire in the dish]. "The leaves can be used any way you would use spinach. One easy way to cook them is this: Steam 2 cups freshly picked leaves for just a few minutes in one cup water, seasoned with an onion, butter and salt. Vary or add other seasons according to your taste. In India leaves are used in vegetable curries, for seasoning and in pickles. Let your imagination be your guide."

Cite this article as:

ECHO Staff 1988. Moringa Recipes. ECHO Technical Note no. 15.