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Answer: Thank you for your recent request for information from ATTRA, the National Sustainable Agriculture Information Service. I am pleased to provide you with information on design plans for hoop houses. Below is a brief introduction to hoop houses along with an extensive list of resources and design plans.
Hoop houses are simple unheated “greenhouse-like” structures that provide less control of environmental conditions than full greenhouses at substantially less cost. They are usually covered with a single or double layer of agricultural plastic and can be built in many different lengths and widths. Extending the season can be achieved with low tunnels that cover planting beds or high tunnels that can be stood in or driven through, or a combination of both. The key to any hoop house design is ventilation which should be addressed in the design phase.
If wind is common in your area, you will need to consider placement for your greenhouse and materials used. Unless you plan to remove plastic for the winter, gothic types are better able to withstand snow loads and wind, compared to multi- bay types. A more sturdy material for greenhouses that have more extreme weather pressure is a rigid polycarbonate material. This material is more expensive, but it will typically weather hail and wind storms and has a 15 year life span. If you already have a structure in place for a plastic film, then it may be easier just to buy another set of film and use extra precautions to insure that it remains intact during a wind storm.
Hoop House Design Resources
The ATTRA web site contains several resources related to hoop houses. One such resource is a webinar that ATTRA Horticulture Specialist, Tammy Hinman, and I presented in 2009. Topics include the uses and benefits of hoop houses, including increases in crop quality and yields; different types of hoop houses; construction, materials and cost estimates; management of crops, soil fertility, pests and weeds; and the economics and marketing of crops. It is available at: http://www.attra.org/video/.
An ATTRA publication that has general information on how to extend the season also includes information on low and high tunnels is Season Extension Techniques for Market Gardeners. This can be accessed online at the following link:
The topic of the April/May 2009 ATTRAnews featured season extension. The newsletter contains a section on design and construction along with an extensive resource section.: http://www.attra.org/newsletter/attranews_0509.html.
Here is a list of non-ATTRA related resources:
-great on-line resource for constructing and utilizing high-tunnels. Site contains several different design plans on how to build simple hoop houses as well as cultural information on growing certain vegetables and fruits in them. It seems to be the best, comprehensive, and farmer-friendly resource about high tunnels on the internet.
Cornell University High Tunnel
-web site provides great information on how to select a site and the correct materials given your climate and property.
University of Vermont High Tunnels
-the following is a link to a great manual on how to properly install a hoop house.
University of Minnesota High Tunnel Production
-site contains information on high tunnel research and link to the newest edition of their high tunnel manual for commercial production.
eXtension – Season Extension for Organic Vegetable Production
- eXtension is an interactive learning environment delivering the best, most researched knowledge from the smartest land-grant university minds across America. This section contains information on hoop houses.
-Milwaukee-based urban farm organization that incorporates aquaponic systems ina high tunnel. Site contains design plans and construction tips for building high tunnels.
Books on High Tunnel Construction:
High Tunnels. Using Low-Cost Technology to Increase Yields,
• Improve Quality and Extend the Season. Ted Blomgren and Tracy Frisch. Download at: http://www.uvm.edu/sustainableagriculture/hightunnels.html
• Four-Season Harvest. Eliot Coleman. Information at http://www.fourseasonfarm.com/books/index.html#harvest
• Winter Harvest Manual. Eliot Coleman. Information at http://www.fourseasonfarm.com/books/index.html#handbook
• The New Organic Grower. Eliot Coleman. Information at http://www.fourseasonfarm.com/books/index.html#grower
The Polytunnel Handbook. Andy McKee & Mark Gatter. Information available at http://nofavt.org/books-merchandise.
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Answer: Thank you for your recent request for information from ATTRA, the National Sustainable Agriculture Information Service. I am pleased to provide you with information on flame weeding.
Flame weeding is a non-chemical weed control technique common among organic farmers. Flame weeding, also called flame cultivation, is dependant on propane gas burners to produce a carefully controlled and directed flame that briefly passes over the weeds (Diver, 2002). The intense heat sears the leaf, causing the cell sap to expand and disrupt cell walls. Foliage that retains a thumb print when pressure is applied between your thumb and finger has been adequately flamed. The flamed weeds soon wilt and die, usually in one to three days.
Weeds are most susceptible to flaming when they are seedlings, 1 or 2 inches tall. Broadleaf weeds are more susceptible to lethal flaming than grasses. Grasses develop a protective sheath by the time they are approximately 1 inch tall and may require a second flaming. Repeated flaming can likewise be used to suppress perennial weeds such as field bindweed.
Flaming on dry, sunny days is recommended (Daar, 2002). Weeds growing in dry areas tend to respond more quickly to flaming than those growing in moist habitats, perhaps because available moisture gives plants more resistance to the heat. When dealing with large areas of weed growth, work in sections, so that areas where weeds have not been flame-killed provide effective fire breaks - just in case some unseen dried material becomes ignited. Green plants undergoing flame-treatment rarely ever ignite.
Most flame weeders are designed to not radiate large amounts of heat. Their purpose is to sear the leaves of plants (weeds) in order to change the protein structure of the plants. As a result, stress is what kills the weeds, not torching them. Due to the design and purpose of flame weeders, there is generally not enough heat produced to penetrate the soil and effect soil life. As stated above, timing is everything.
While most articles focus on the weed control benefits of flaming, this technique also has other pest control applications (Daar, 2002). For example, potato plants up to eight inches (20.3 cm) tall can be flamed to kill Colorado potato beetles, Leptinotarsa decemlineata, without causing undue damage to the potato plants. Flamers can also be used to incinerate fallen fruit and mulch that harbors over-wintering spores that cause powdery mildew, brown rot, and other plant diseases. Given their versatility, flamers appear to be very useful garden tools - particularly for those seeking alternatives to toxic materials.
ATTRA offers two publications on flame weeding; one for vegetable crops and the other for agronomic crops. Both of these publications are available online at the links stated below. You can also request a hard copy of these publications by contacting ATTRA by telephone at 1-800-346-9140.
Daar, Shelia. 2002. “Flame Weeding in the Garden.” Brisbane: Gamaco Pty Ltd, Retrieved Feb. 9, 2007
Diver, Steve. 2002. Flame Weeding for Vegetable Crops. Fayetteville: ATTRA.
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Answer: Thank you for your recent request for information from ATTRA, the National Sustainable Agriculture Information Service regarding grants, loans, and other financial assistance for a solar electric system.
Focusing just on solar, there are a number of incentives you may be eligible for to reduce the overall cost of your solar project.
If you are using electricity on your farm (your home energy needs are not eligible for the program) you may be eligible for the Rural Energy for America Program (REAP). REAP provides a 25 percent grant for solar power to be installed on the farm. The minimum amount of a REAP grant for a solar system must be $10,000 and applying for the grant is quite complicated. Farmers usually hire a “grant packager” to perform an energy audit on the farm and write the majority of the grant application. In addition to the grants, you may also apply for a REAP guaranteed loan in the amount of 50 percent of the total project costs. More information regarding REAP is available at http://www.rurdev.usda.gov/rbs/farmbill/index.html.
The Property Tax Exemption for Solar is a local option that your county may have opted into. To see the list of counties participating in this program and whether your county is one of them, visit http://www.dsireusa.org/solar/index.cfm?ee=1&RE=1&spf=1&st=1.
Because solar power is very expensive, it is almost always better to focus on energy conservation and energy efficiency first. There are several energy efficiency programs that you are likely eligible for.
The Residential Renewable Energy Tax Credit program is a federal tax credit which allows you to “write-off” up to 30% of a solar projects’ costs. This requires that you have taxable income. However, you can write the project costs off each year through 2016. More information on this tax credit is available at http://www.dsireusa.org/incentives/incentive.cfm?Incentive_Code=US37F&re=1&ee=1.
You may be eligible for the Income Tax Deduction for Energy-Efficient Products. This program provides an individual tax deduction of 20% for things like clothes washers, refrigerators, ceiling fans, lighting, central air conditioners, and thermostats. More information on the program is available at http://www.dsireusa.org/incentives/incentive.cfm?Incentive_Code=VA39F&re=1&ee=1. Additional cash rebates for these and other appliances are available through the Residential Energy-Efficient Appliance Rebate program. Information on this program is available at http://www.dsireusa.org/incentives/incentive.cfm?Incentive_Code=VA31F&re=1&ee=1.
There are many no- or low-cost measures you can take to reduce your power bills. Take a look at the tips listed on the AEP website at https://www.appalachianpower.com/save/Default.aspx.