No

No, lake, S central Sudan, in the swampy Sudd region. It is formed by the floodwaters of the White Nile and varies in size seasonally. Its maximum area is c.40 sq mi (100 sq km). Much papyrus grows in the lake.

No, symbol for the element nobelium.

No: see Asian drama.

or till-less agriculture

Cultivation technique in which the soil is disturbed only along the slit or hole into which seeds are planted. Reserved detritus from previous crops covers and protects the seedbed. Primary benefits are a decreased rate of soil erosion; reduced need for equipment, fuel, and fertilizer; and significantly less time required for tending crops. The method also improves soil-aggregate formation, microbial activity in the soil, and water infiltration and storage. Conventional tillage controls weed growth by plowing and cultivating, but no-till farming selectively uses herbicides to kill weeds and the remains of the previous crop. No-till farming is one of several primitive farming methods revived as conservation measures in the 20th century.

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known as Hitomaro

(died 708, Japan) Japanese poet. He entered the service of the imperial court and later became a provincial official. Japan's first great literary figure, he lived when Japan was moving from a preliterate to a literate, civilized society. His writings, on a wide range of subjects, balance the homely qualities of primitive song with sophisticated interests and literary techniques. All 77 poems accepted as indisputably his, and many others attributed to him, appear in the Man'yoshu, the first and largest of Japan's anthologies of native poetry.

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No-dig gardening is a cultivation method favored by many organic gardeners. Japanese Masanobu Fukuoka started his pioneering research work in this domain in 1938, and the Fukuokan philosophy of "natural farming" is now acknowledged by some as the tap root of the Permaculture movement. No-dig gardening subsequently spread to and is adapted by numerous actors in the field, including Australian Esther Deans.

Function

While digging can damage soil life , not digging can preserve it, but requires that micro-organisms be enticed to the surface where they will excrete and aerate the soil by burrowing to keep the dynamic relationship between surface and depth . Adding organic matter and weather protection can entice them to the surface: this is what no-dig gardening does.

Digging history

The primary reasons for digging the soil are to remove weeds, to loosen and aerate the soil and to incorporate organic matter such as compost or manure. In countries with thin soil and high erosion there is a strong case against digging, which argues that in the long term it can be detrimental to the soil's health. While digging is an effective way of removing perennial weed roots, it also often causes seeds (some can remain dormant for many decades) to come to the surface and germinate. Digging can also damage soil structure, cause problems like compaction, and disturb and unbalance symbiotic and mutualist interactions among soil life. Also, by exposure to the air, digging tends to use up nutrients which then need to be replenished. Digging is practiced traditionally in countries with deep rich, old soils such as Western Europe, however this is traditionally followed by periodic resting of the soil.

Methods

No-dig methods rely on nature to carry out cultivation operations. Organic matter such as well rotted manure, compost, leaf mold, spent mushroom compost, old straw, etc, is added directly to the soil surface as a mulch at least 2 or 3 inches deep, which is then incorporated by the actions of worms pulling it downwards. Worms and other soil life also assist in building up the soil's structure, their tunnels providing aeration and drainage, and their excretions bind together soil crumbs. No-dig systems are said to be freer of pests and disease, possibly due to a more balanced soil population being allowed to build up in this comparatively undisturbed environment, and by encouraging the buildup of beneficial rather than harmful soil fungi. Moisture is also retained more efficiently under mulch than on the surface of bare earth.

Another no-dig method is sheet mulching wherein a garden area is covered with wetted paper or cardboard, compost and topped off with landscape mulch.

Converting to a no-dig system is easier than digging. It is a long term process, and is reliant upon having plentiful organic matter to provide mulch material. It is also necessary to thoroughly remove any perennial weed roots from the area beforehand, although their hold can be weakened by applying a light-excluding surface layer such as large sheets of cardboard or several thicknesses of spread out newspaper (overlapped to provide thorough cover) before adding the compost mulch. When using newspaper, shiny, glossy paper (such as advertisements) should be avoided. These do not break down readily. The newspaper or cardboard should be thoroughly wet as well. A popular book, Lasagna Gardening by Patricia Lanza (Rodale Press, Inc.) provides excellent instructions for the novice user.

Benefits

No-dig gardening systems are strongly recommended by Dr. Shewell Cooper of the Good Gardeners Association. A full description of how to make a no-dig garden can be found a at http://www.permaculturevisions.com/no-dig.html.

References

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See also

Aquaponics
Masanobu Fukuoka Farming
Veganic gardening
Sheet mulching
Permaculture