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Home  > Question of the Week

Question of the Week

Permalink Can I use my livestock watering system throughout the winter? How can I keep it from freezing?

Answer: Livestock producers have two options when deciding how to water their livestock during the cold months: to winterize a summer-use system or freeze-proof the current system and use it through the winter. Either way, planning ahead is key to avoiding costly labor, parts, and repairs.

If you choose to winterize a system, the first thing you must do to turn off the system at the pump controller. For a system with a submersible pump, water in the well's supply pipe must have a way to drain below the freeze level. At the end of the pumping season, and long before freezing weather occurs, turn off the pump and close the hydrant. Any above-ground piping must be drained.

For a system with a surface pump, any above-ground piping that will be exposed to freezing temperatures must be completely drained. The pump and suction line must also be completely drained. The pump should be covered.

If you plan to use a watering system when pipes and water troughs can freeze, you will need to plan ahead. If you use a solar-powered system, keep in mind the solar panels stop generating power at night, when temperatures are lowest. Also, solar electric technology is good for pumping water but not very good for electric resistance heating. You have several options to prevent freeze-up, including using heat from the earth (geothermal) or sun, insulating components or continuously circulating water.

For more information, see the ATTRA publication Freeze Protection for Livestock Watering Systems, available at

Another option is to use an insulated livestock waterer in the manner suggested by the government of Alberta's Agriculture and Food program. This program has tested low-input, energy-free livestock water delivery and heating technology that relies on geothermal heat to keep water open during cold weather (as low as -15 degrees Fahrenheit).

To learn more about the construction, use, and maintenance of the energy-free system, see the publication Energy Free Water Fountains, available at$department/deptdocs.nsf/all/eng3133/$file/706.pdf?OpenElement.

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Permalink What are some organic-friendly ways I can manage the staggering weed problem in my banana crop?

Answer: Generally in organic systems, preventive weed control is the most effective method of dealing with weeds. As for what can assist you now, a combination of approaches is likely necessary, as you almost certainly have some weeds that you can control with mulches and others that you cannot. Various approaches include the use of geotextiles (fabric mulch), wood chip mulch, mowing, some hand-weeding around young trees, flame weeding, chickens or weeder geese, and some of the organic herbicides. Try everything you can to keep from disturbing the soil with cultivation, but if you simply can’t manage that, you may find the Weed-Badger to be effective with minimal soil disturbance.

As for organic herbicides, some find a citric acid-based one to be most effective, but soap-based and vinegar-based (acetic acid) ones also do the job. Of course, there is no systemic organic herbicide, so all of these organic herbicides are "contact" herbicides only, i.e., they are only affective on what they come in contact with. These don't work especially well on any established weeds—the sprayed part wilts, but the weed sends up new growth almost immediately. As a consequence, achieving decent weed control on established weeds can be prohibitively expensive. However, if you time the use of these organic herbicides so that they're being employed against small, young weeds, you can get some decent control from them.

See the ATTRA publication Tree Fruits: Organic Production Overview for information on weed management both prior to orchard establishment (pages 10-11) and in established orchards (pages 22-24). It is available at

Also see ATTRA’s Biorationals Database for more information on organic herbicides and ecological pest management, available at

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Permalink Can you suggest a way to get rid of wild onion?

Answer: Wild onion is a difficult weed to control because the hollow leaves are very waxy and repel spray materials very well. A combination of strategies may work best to help manage wild onion on your land.

Hand pulling is an option if there are only small clumps. For best results, you should use a trowel, ditching spade, or trenching tool. In northern areas, many people often dig the wild onion in late fall when they are sure they are going to get a longer spell of freezing weather (in the 20o F range) and leave the bare bulbs on the surface to freeze for a good week to 10 days.

There are also chemical options that work in turf grass settings. Each of these herbicides has restrictions on the type of grass they can be used on. Some people have found the glyphosate products to be weak on the onion/garlic weeds and the metsulfuron are labeled for use only by licensed landscapers. The "three-way" products can be readily purchased over the counter. The timing for control is ideal.

For more information, see ATTRA publication Principles of Sustainable Weed Management for Croplands, available at

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Permalink What can you tell me about bio-heated greenhouses?

Answer: A bio-heated greenhouse most often refers to the practice of generating heat in a greenhouse from animals, but it can also refer to using compost. The following information focuses on the use of animals in a greenhouse as a heat source. For information on composted heated greenhouses, refer to the ATTRA publication Compost Heated Greenhouses, available at

Generating heat in a greenhouse from animals is primarily accomplished using small livestock, such as chickens and rabbits. Farmer Anna Edey, of Solviva Solar Greenhouse, successfully raises chickens and rabbits in her solar and bio-heated greenhouse. She tried to incorporate small ruminants into her greenhouse operation but discovered that the heat generation from the sheep flock was not significant. Growing Power, an urban farm nonprofit, uses aquaculture to heat its greenhouses.

Generally, there are two main reasons to incorporate animals into a greenhouse. First is the biothermal heating produced by the animals. According to Edey, chickens and Angora rabbits each contribute about 8 BTUs per pound of weight, which she states is the equivalence of 2½ gallons of fuel oil per animal per heating season (1). The second reason is to create a bio-shelter. The bio-shelter serves as both an animal shelter and as a greenhouse, which can help reduce costs. Edey has written the book Solviva — How to Grow $500,000 on One Acre & Peace on Earth, which is available at bookstores, libraries, or on the Solviva website:

While rabbits and chickens can provide warmth in a greenhouse, it is important that they receive adequate ventilation as the higher temperature and humidity of a greenhouse are generally not healthy for animals. Ventilation is very important in preventing a build-up of ammonia and preventing the spread of diseases.

Edey uses an "earth-lung" to filter out the toxic ammonia gas from the rabbit and chicken manure, and her chickens are kept in a poultry room in the greenhouse where temperatures do not fluctuate from about 70º F (1). She does not have a backup heating system for cloudy days and does not believe it to be necessary. She believes that the carbon dioxide emitted by the animals enhances plant growth in the greenhouse. The manure is composted.

(1) Anon. 1998. Producer Grants: Michigan: Permaculture Greenhouse System: Integrating Greenhouse and Poultry Production. North Central Region SARE, 1998 Annual Report, University of NE, Lincoln, NE.

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