To develop technical methods for the creation of the visually attractive sward abundant in wild flowers, germination characteristics, cutting propagation, and frequency and timing of mowing was studied on one of the typical wild flower, Aster ageratoides subsp. ovatus Kitam.
Seeds showed good germination at 15-25°C, even under dark conditions. Under light conditions they recorded high germination percentages even at 30°C. Seeds in dry storage below 25°C could keep their germination ability for at least one year.
Therefore, whenever good water is able to be provided, good seasons for sowing seem to be wide in range.Where seeds were sowed in April, flowers were observed in the autumn of that year.
As far as irrigated suitably after cutting treatment, roots developed from 90% of cuttings.
Sufficient flowering was maintained and the height of sward was controlled to 20-30 cm by early July mowing, or early June and early August mowing. A poor flowering state was induced, on the other hand, by Septembe mowing.
Because of the good temperature for germination and the considerable effect of cold stratification, seeds dispersed in December in the field may sprout in early spring after cold and wet winter. Thus, the sward will extend. Individual plants regenerate with rhizome.

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The effects of soil water stress on the stomatal and cuticular transpiration rates were examined by means of the transpiration measurements with cut branches for eight tree species (Pinus densiflora, Cryptomeria japonica, Juniperus conferta, Quercus glauca, Zelkova serrata, Caragana korshinskii, Hedysarum scoparium and H. mongolicum) growing under four different soil water levels. The stomatal transpiration rates for all species were depressed by the water stress sustained during growth period. The reaction time of stomatal closing after leaf detaching was seldom affected by water stress. J. conferta and P. densiflora (new needle) needed relatively long period for their stomatal closing. On the other hand, Q. glauca, Z. serrata and Cr. japonica could close their stomata in relatively short period. Except the cases of P. densiflora and Q. glauca, the cuticular transpiration rates were suppressed with the degree of soil desiccation. Water stress affected on stomatal transpiration rates of Q. glauca and P. densiflora (new needle), and on cuticular transpiration rates of Z. serrata and Cr. japonica. For the xerophite species, such as Ca. korshinskii, J. conferta and P. densiflora (old needle), both rates of transpiration were modified with water stress.

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To purpose of weed control, plant length inhibitor and flowering beautifully, this experiment sprayed growth inhibitor on four species herbaceous flowering plants.
The kind of experimental herbaceous flowering plants were Cosmos bipinnatus Cav. “sensation”, Cosmos sulphureus Cav., Rudobeckia hirta L., Coreopsis tinctoria Nutt.
Growth inhibitor applied to Dikegulac-sodium (C₁₂H₁₂O₇N_a), Flurprimidol (C₁₅H₁₅F₃N₂O₂), Paclobutrazol (C₁₅H₂OClN₃₀) with low and high levels.
The results of this experiment that every growth inhibitors were ineffective against Cosmos bipinnatus Cav. “sensation” . But Flurprimidol (C₁₅H₁₅F₃N₂O₂) of 0.2g/m² or 0.1g/m², and Paclobutrazol (C15H2OClN30) of 0.4 me/m² were so effect against Cosmos sulphureus Cav., that the plant length inhibited from 52.8%-72.8%. Besides admirable term was to be long.
Flurprimidol (C₁₅H₁₅F₃N₂O₂) of 0.1g/m² and Paclobutrazol (C₁₅H₂OClN₃₀) of 0.4ml/m² were so effect against Rudobeckia hirta L., that the plant length inhibited from 55% or 77%. Besides admirable term was to be long, the leaf area andewer diameter was to be large.
Flurprimidol (C₁₅H₁₅F₃N₂O₂) of 0.2 g/m² or 0.1 g/m², and Paclobutrazole (C₁₅H₂OClN₃₀) of 0.4ml/m² were so effect against Coreopsis tinctoria Nutt., that the plant length inhibited from 75% and weeds were controlled. Besides admirable term was long and the number of flower was increased.

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[in Japanese]

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