The study was intended to know the feasible productivity formation of Chinese cabbage under the various weeding conditions, namely, the plots such as weed-free, two times hand weeding, ⅓ weeds of weedy check left, ⅔ weeds left, and complete weedy check. Experimented cabbage cultivar was $quot;Samzin$quot;, and planted on the college farmland at Kwangju, 1979. With three replications in RBD, the crop was transplanted at Sep. 10 in space of 45×60㎝. The results concerned with were as follows:
1. On the experimental farm, mostly Digitaria, Portulaca and Artemisia sp. were dominated, and during later seasons Stellaria and Alopecurus sp. were succeeded.
2. Crop growth seemed to be affected by the density of weed populations at the beginning, however the estimated variations in crop products were detected around 20 to 40 days after transplanting.
3. Responding to decrease of weed populations during later growing seasons, the crop growth in weedy check and hand weeding plot reoccurred.
4. No differences were detected between plots of ⅓ weeds left and ⅔ weeds left, and the results indicate the weed amounts as ⅓ weeds left are enough to compete with the crops.
5. Fundamental differences in carbon-assimilation rate and speeds were well recognized between both crops and weeds. On this respects, even though bigger population of weeds affects a little the net product, however less harzards of crops do much affects on the net-product formation per a given area.
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