For the establishment of weed suppression system applying paper slurry on soil surface, influences of the level of grinding and the amount of paper slurry were examined. The radish (Raphanus sativus L.) was used for test instead of weed to clarify the effect of suppression against bud emergence.
1) The paper slurry with medium grinding showed good effect on suppressing bud emergence when paper slurry was applied more than 250g/m².
2) The paper slurry with fine, medium and rough grinding were effective on suppressing bud emergence when paper slurry was applied more than 250g/m².
3) Regarding the combination of the grinding condition and the amount of paper slurry, significant effect is expected when fine or rough grinding paper slurry is applied 500g/m², or medium grinding paper slurry is applied more than 250g/m².
4) For the suppression of bud emergence, the paper should be ground as the fiber length to be around 1.0mm and applied on soil surface with the thickness of around 0.4mm.

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In previous experiments to evaluate the speed of composting of tree pruning chips, we determined that physical properties of the chips greatly affect the length of time that composting takes, the work involved-such as the number of times the compost must be turned-as well as the amount of additional water required. A previous experiment with composting of chips in 1m³ reactors, after secondary processing involving crushing in a screw-pressure type crusher, showed that moisture content of these chips remained above 40% during composting, and fermentation completed uniformly in 60 days using only aeration and without turning of compost. This report discusses our finding-that water absorptivity and water retentivity are good criteria for quantitatively evaluating the ease of composting of chips from tree pruning-and the validation of these criteria by experiments with composting of three types of chips in 1m³ reactors. Results of the experiments were as follows:
1) Ease of composting was a function of the water absorptivity (mass of absorbed water/mass of air-dried chips) and the water retentivity (moisture content loss/day) of chips, but not a clear function of the chip size distribution.
2) For chips cut with a cutter-knife type chipper (the conventional processing method), the water absorbability was improved 1.6 times and the water retentivity was improved 1.3 times by secondary processing using a screw pressure type crusher.
3) Chips that had both sufficient water absorbability and sufficient water retentivity were suitable for composting by aeration alone, without requiring turning of compost.
4) Short term measurements (over about 7 days) of water absorbability and water retentivity were sufficient for quantitatively evaluating suitability of chips for composting.
In conclusion, we found that our proposed criteria for evaluating the suitability of tree pruning chips for composting was useful not only for quickly evaluating different types of chips but also for facilitating crusher development work.

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Using some cover crops in vegetable production is expected that it can be beneficial to the cultivation such as reduction of erosion or splashing by covering the soil surface, weed control by shading sunshine or allelopathy, enrich ecological diversity by securing hangout for insects and nitrogen fixation or catching of surplus nutrition. And in cultivation under the living mulch with minimal tillage, the application of basal fertilizer is very important. In the shaft tillage cultivation that was devised by authors, these application method is influential elements for the growth of crops cause of competition of nutrition with weeds and salt injury at taking root.
In this report, a tool for shaft tillage cultivation equipping with injector of paste type fertilizer, which enable to simultaneous operation of tilling and fertilizing, was tested on trans-planting cultivation using of Chinese cabbage plug seedling. The results were as follows:
1) Tool for shaft tillage cultivation equipping with injector of paste type fertilizer was usefulness in simultaneous operation of tilling and fertilizing, but the fertilizer was overflowed without penetrating into the soil under the certain soil conditions. And the growth of some seedlings were influenced.
2) Since the growth of seedlings under the condition of solid type fertilizer with surface broadcasted application, it were suggested that there is no difference in competition of fertilizer between applications of surface broadcasting and under seedling penetration.
3) The differences of the seedlings' growths were clearly appeared the 2nd day from transplanting.

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The purpose of this research is to evaluate the developed weed cutter with wheels by making a comparison to a conventional one with a shoulder belt through the workers' feelings.
By using the Analytic Hierarchy Process method, the hierarchical structure for evaluation is constituted of the “load to body”, the “operating utility” and the “noise”. The “load to body” is composed of the five elements, which are the “burden to heart”, the “fatigue of legs, waist, arms and shoulders”. The “operating utility” is structured by the “safety of work”, the “cutting neatness” and the “adjustability to surface”. Then the pair wise comparisons between the two weed cutters are carried out on each element.
The results are as follows;
1) The “operating utility” is more weighted than the “load to body” and the “noise” isn't taken seriously so much.
2) On the point of the “operating utility”, the “safety of work” is weighted comparatively and the “adjustability to surface” is followed. The “cutting neatness” isn't considered as an important factor.
3) The “fatigue of legs and waist” is the most weighted and the following is the “fatigue of arms and shoulders”. A few thinks the “burden to heart” is important.
4) The conventional weed cutter has superiority only on the “cutting neatness” and the “adjustability to surface”. On the other elements, the developed one has superiority.
5) The developed weed cutter is appreciated entirely by all evaluators except one whose conclusion is equal, if the importance of each element is considered.

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