Individual wet clay particles are slippery, slide together, pack densely and close in the macrospores
of the soil that are needed for aeration and drainage.
Recent spread of the pathogen around the world has focused attention on macrospores
germination which is the most important factor in creating epidemics of ergot disease.
The highly aggregated Redland soil with stable aggregates and a reasonably high proportion of inter-aggregates macrospores
allowed rapid percolation of treatment solution into the soil bed and some exchange between added Na ions and Ca and Mg ions present on its exchange sites during the saturation phase of this soil.
From Figure 3, it can be seen that after low-temperature treatments, the proportion of microspores (0-10 nm) decreases, the proportion of small pores (10-100 nm) increases, the proportion of mesopores remains the same, and the proportion of macrospores
increases to some extent.