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Two-wheel tractor or walking tractor are generic terms understood in the USA and in parts of Europe to represent a single-axle tractor, which is a tractor with one axle, self-powered and self-propelled, which can pull and power various farm implements such as a trailer, cultivator or harrow, a plough, or various seeders and harvesters. The operator usually walks behind it or rides the implement being towed. Similar terms are mistakenly applied to the household rotary tiller or power tiller; although these may be wheeled and/or self-propelled, they are not tailored for towing implements. A two-wheeled tractor specializes in pulling any of numerous types of implements, whereas rotary tillers specialize in soil tillage with their dedicated digging tools. This article concerns two-wheeled tractors as distinguished from such tillers. ==Confusion over definition== Research has identified a number of terms used to identify two-wheel tractors, including "walk-behind tractor; iron-ox; walking tractor; mechanical ox; ox-machine; pedestrian tractor; hand tractor; single-axle tractor; and in Asia, tok-tok".〔Ericson, Matthew (2010). 'Two-Wheel Tractors: Road Safety Issues in Laos and Cambodia.' Safety Science 48(5): 537-43.〕 There is also a fair bit of confusion in nomenclature regarding machines of similar size/configuration, that operate a single implement (such as power tillers; rear-tine tillers; rotary hoes; rotary ploughs; rotary tillers; Rotavators; etc.) The important distinction between a two-wheel tractor and any of these machines is that the two-wheel tractor is a single-axle, walk-behind machine designed to operate multiple interchangeable implements, where machines in the categories above typically only operate one implement (such as a tiller), which implement is often integral to the machine (rather than being removable). "Power tiller" can be understood as a garden tiller/rototiller of the small () petrol/gasoline/electric powered, hobby gardener variety; they are often sold as a rotary tiller, though the technical agricultural use of that term refers solely to an attachment to a larger tractor. Alternatively, the terms "power tiller" or "rotary tiller" are always understood in Asia and elsewhere to be rubber- or iron-wheeled, self-propelled machines of and usually powered by heavy-duty single-cylinder diesel engines (many Asian countries historically have had a high luxury tax on petrol/gasoline). Adding to the nomenclature confusion, agricultural engineers like to classify them as single-axle tractors. For clarity, the rest of this article refers to the self-propelled, single-axle, multi-attachment tractive machines as two-wheel tractors. For production agriculture, past and present, two-wheel tractors accept a wide range implements, such as the following: For soil-working: rototillers, moldboard plows, disc-plows, rotary plows, root/tuber harvesting plows, small subsoiler plows, powered and non-powered harrows, seeders, transplanters, and planters. Even zero till/no-till planters and seeders have become available. In plant protection and weed control, two-wheel tractor implements consist of various inter-cultivators and sprayers. For harvesting, available implements are: Forage: Sickle bar mowers, disk mowers, hayrakes, hay tedders, haybalers and bale wrappers (silage production ). For grain harvest: reaper/grain harvesters, reaper-binders, and even combine harvesters are available (typically only for Asian two-wheel tractors ). For transport, trailers with capacities from 0.5 to 5 plus ton cargoes are available. General mowing implements consist of lawn mowers, brush mowers, and flail mowers. For snow removal, implements consist of snowblowers, power sweepers, and snow/dozer blades. Other implements include: chipper/shredders, log splitters, electrical generator, pressure washer, crimper-roller, fertilizer/salt/lime spreader, and stump grinder. This list of implements (which may not be complete) means that two-wheel tractors can execute practically all of the chores done by larger 4-wheel tractors, with the exception of items like front-loaders, which obviously have the physical stability requirements of a 4-wheel (two-axle) tractor. This confusion over, or perhaps just ignorance of the utility of 2-wheel tractors, persists even at research and institutional levels. The United Nation's Food and Agriculture Organization's own statistical database, FAO Stat 〔(Faostat )〕 gauges levels of agricultural mechanization by numbers of 4-wheel tractors and ignores completely the fact that 2-wheel tractors often perform much, or even exactly, the same work as done by 4-wheeled models. By using FAO's statistics, international donors and agricultural research and development centres assume, as Bangladesh and Sri Lanka have very few 4-wheel tractors, that they are completely unmechanized compared to (e.g.) India, which has a large population of them (besides 100,000 two-wheel tractors ). Yet, when two-wheel tractors are included, Bangladesh and Sri Lanka are the most highly mechanized countries in south Asia in terms of area farmed using mechanized tillage. Two-wheel tractors are also extremely common for agricultural use in the mountainous countries of Europe (Italy, France, Spain, Germany, Switzerland, Austria, etc.), and as of 2015, there are at least 15 brands of two-wheel tractors of Italian origin alone. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Two-wheel tractor」の詳細全文を読む スポンサード リンク
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