The spraying skill of the worker was evaluated by deposition index of the water sensitive paper. We compared the amounts of deposit when 6 workers sprayed by power sprayer. The eggplant model, made by suppor pipes was used for this investigation. The results were following;
1) Only some workers can stain the water sensitive paper as target on eggplant model, following exposure to the spray.
2) When the height of eggplant model was 2m, the deposition index was lower than the case of 1.2m or 1.6m.
3) Spraying skill was different among workers and the difference was due to their experience of spray.
4) Teaching from workers who have been experienced spraying the improvement of spraying movement for few experience one made the deposition index higher.

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The mowing efficiency, resistance force imposed on the bush cutter control shaft, and burden on the operator's muscle were investigated and compared with conventional blades to discover a shape of the fixed blade which is suitable for mowing weeds and grass. The following is a summary of the results of the investigation.
1) Mowing efficiency of the 23-tooth fixed blade is higher and more stabilized than that of 19-tooth and 45-tooth fixed blade, with engine speed of over 6, 500rpm in operation.
2) The pitch of the cutting edge of the 45-tooth fixed blade is too small to cut all the grass and inevitable inching operation results in a conspicuous decline of mowing efficiency, especially in a higher range of running speed of the rotary blade.
3) The fixed blade having 19 teeth has a cutting edge of a wide pitch, so that it takes in a large amount of grass stems. However, it supports only part of the stems, and most of them are pushed down by the rotating cutting blade before they are cut. To prevent this, it is necessary to reduce the amount of grass for the fixed blade to take in. For this reason, mowing is done by slowing the travel speed of the bush cutter. Consequently, the mowing efficiency did not increase in this test, too.
4) The degree of mowing resistance inflicted on the control shaft in directions of right and left, and up and down was measured. With the fixed blade, the resistance on the right and left side was on the lowest level with engine speed of about 6, 500rpm in operation and the resistance increased with the engine speed below and above 6, 500rpm. This phenomenon is reverse to that of mowing efficiency. The phenomenon can be explained as follows. (1) While a lower engine speed allows the cutter to take in more grass stems, the cutting capability can not catch up with the fast speed of the cutter movement which is set in the experiment. (2) A faster engine speed accelerates the rotary speed of the blade which causes some grass stems to be pushed by the outer periphery of the blade. The above phenomenon was more conspicuous with 19-tooth and 45-tooth fixed blades than with 23-tooth fixed blade.
5) The degree of mowing resistance on the control shaft in directions of up and down was the same on different types of the fixed blade. With the fixed blades, the resistance was on the puls (up) side, the reason being that the grass stems, after being cut, worked to push the bottom of the rotary blade upward. With an ordinary cutting blade, the resistance was on the minus (down) side, the reason being that the grass was cut down and left on the cutting blade. The grass accumulated on the blade worked to push the blade downward.
6) Surface electro-Myogram on 8 points of the operators shoulders and arms was measured. With both of the fixed blade and ordinary blade, a strong electric emission was recognized on the left shoulder muscle (M. trapezius), where the suspension belt is placed and on the arms muscles (M. branchioradialis), the area to support cutter's handle operation. The electric emission signifies muscle strain.
7) Electric emission from the left M. trapezius and left M. branchiordialis in using an ordinary blade, was less than that in using the fixed blade, because the weight of cutting head of the ordinary blade was lighter than that of the fixed blade by about 0.5kg. But, the emission from the right side muscles, in using the ordinary blade, was more than that in using the fixed blade. The increased electric emission from the right side muscles in judged to be attributed to the increased mowing resistance (in directions of up and down) caused by the grass clippings accumulated on the blade, and to bending and twisting for arms to throw the grass clipping on the blade. To ascertain the judgment, the weight of the cutting head of the ordinary blade was adjusted to the same weight as of the fixed blade, to make comparison in the electro-myogram.

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In order to investigate a multi-sided efficacy of “A no-tillage and mulching farming system incorporated fruit cropping”, this paper presents some influences of several mulch and tillage methods on weed vegetation and soil fauna.
1) In tillage treatments, perennial weeds with bulb and rhizome dominated, but biennial and perennial weeds of Compositae disappeared, while weed vegetation in no-tillage treatments was unripen farm type including many perennial weeds with long subterrancean stem.
2) It seemed that the number of species, coverage and species diversity in weed decreased as the artificial effect of tillage treatment and the degree of the addition of mulch increased.
3) It was observed that many naturalized weeds invaded the fields in mulch and no-tillage treatments, but influences of artificial disturbance varied for individual species.
4) The individual numbers and numbers of species of macrofauna decreased by tillage treatments and the following bare ground condition. A maintaining the mulch and no-tillage management resulted in the change of species and appearance of several rare species.

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The authors built a sumulation model of optimum design of volunteer wheat plants (VWP) Control system including a germination model of VWP in the winter wheat-summer crop-barley rotations.
This allowed the authors to examine thoroughly the relation between the VWP control system and net income in winter wheat-summer crop-barley rotations by simulation. The following items regarding the VWP control system were investigated.
(a) No measures taken to control VWP (system N).
(b) Hand picking of VWP just before the barley harvesting (system H).
(c) Tillage system of plow-tilling in summer followed by rotary-tilling in autumn (system P).
(d) Tillage system of rotary-tilling after 3 weeks of wheat harvest followed by tilling in late in November (system L).
(e) Calcium cyanamid treatment of the soil after wheat harvest (system C).
(f) Operation of rough rice separators to remove contamination (system S).
The results obtained are as follows;
(1) Winter wheat-soybean-barley rotation
The highest net farm income was produced by system P, followed by system S, C, H, L and N in that order.
(2) Winter wheat-buckwheat-barley rotation
The highest net farm income was produced by system C, followed by system P, S, L, H and N in that order.
As a result of the field experiments and simulation, it is considered that the new control system of VWP has a great significance in winter wheat-summer crop barley rotations.

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