Virus infection early in the season could affect the results, whereas virus infection late in the season is less likely to do so. It is essential to propagate plants used for cuttings at a location free of aphids. Photographs of virus affected clovers are shown here Need for Uniform Protocols To ensure valid comparisons of response of the white clover system from location to location, the following protocols should be uniform at all locations. Pot size and shape. 15 liter volume with surface diameter of approximately 30 cm.
Uniform rooting medium surface area is essential.
Large rooting volume allows up to 4 months of growth without pot binding. Rooting medium, fertilization method and irrigation method. One commercial rooting medium that can be obtained by all groups. 28 day growth periods. Meteorological and Ozone Measurements.