Tractor design

The degree of damage caused to the soil by a tractor depends on the weight, which is distributed over the area covered by the tyres. It should be borne in mind that in spite of an equal specific load on the soil (contact area pressure) a heavier tractor (even if it has bigger tyres) will exert greater pressure on the soil. 

The basic rule is drive into the orchard as little as possible, and with as light a tractor as possible. Only a light tractor weighing less than 2000 kg, and with broad tyres (at least 35 cm), conserves the larger pores of the soil. 

In terms of construction, the most suitable tractors are articulated ones which in addition to a low total weight have a favourable weight distribution (60% on the front axle and 40% on the rear axle). This type 

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Truck A self-propelled commercial motor vehicle (other than a truck tractor) designed and/or used for the transportation of property. 

On all grades above 5 percent, the individual manufacturer should be consulted since a variety of other factors which must be considered vary with individual tractor designs. Minimum safety criteria for industrial tractors are covered in OSHA Standard Section 1910.178 (Powered Industrial Trucks) and should be referred to when equipment is being selected. 

A field operator exposure study was designed to accommodate the chemical properties and the use pattern involved in the treatment of potato crops for protection against the Colorado potato beetle. Fifteen farmworkers experienced in the use of tractor-drawn sprayers for application of crop protection materials to crops were selected. All were adult males. To avoid production of a large quantity of treated potato crop prior to registration of the product for sale, the trials were performed on stubble fields after harvest of winter wheat crops in a potato-growing area of southern Ontario. This allowed the use of typical farm spray equipment and a typical duration of exposure for a complete shift of work. 

For blending of soil in the range of 2 to 5 ft deep, such as may occur in shallow ponds or soil piles, a tractor-mounted rotary tiller can be used. Tillers are designed for thorough mixing, provided the blending agent is properly dispersed over the surface. 

As far as efficacy is concerned, this is a model of procedural memory with more than a sensorimotor aspect, because it includes considerations of instinctive priority and emotional salience. It is thus the Freudian unconscious broadened and made user-friendly. No longer a cauldron of dread desire, my unconscious procedural repertoire is both rich in sources and ready to respond. I don t have to think about most of what I do. It just happens automatically, appropriately, and adaptively. My emotional brain knows that helicopters, Vermont tractors, and nervous exhibit designers have something in common. 

MGC/PLASMOX developed a portable unit, Model RIF 2, that was put into operation in 1994 and has since built additional units. The RIF 2 is skid-mounted and designed to be moved by four standard tractor-trailers. The unit has been used in Europe and is permitted under both Swiss and German environmental laws and regulations. It was used successfully to destroy chemical agents for the Swiss Army at its chemical materiel laboratory in Spiez, Switzerland. The PLASMOX tests run by the Germans and Swiss indicate that the system will destroy chemical agent safely and rapidly (Bums and Roe, 2001). 

Field Plot Technique. Herbicide treatments were made to plots measuring 3.1 to 6.1 by 13.2 to 18.3 m arranged in a randomized complete block design with 3 replications. Herbicides were applied with tractor-mounted compressed air or C0 backpack sprayers delivering 187 to 280 L/ha at 139 to 207 kPa. Herbicides were uniformly mixed with the top 8 to 10 cm of soil with 2 pass incorporation. 

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