My garden soil in Jacksonville, OR is heavy clay that dries out and becomes
hard and water resistant during summer. Water can puddle on the surface, but
if the soil is scratched, it is bone dry a quarter of an inch below, and
plants would die of drought in spite of frequent watering.

I found by experiment that if ammonium sulphate is sprinkled on the clay and
watered, it gradually sinks in, and when enough is applied, the clay becomes
soft, crumbly and permeable to any desired depth. Plants that previously had
wilted now grow well in it. Clay soil in the Sunland - Tujunga area of SoCal
has been found to respond in the same way.

No reference to this effect has been found in garden books or on the
Internet, and no gardeners of my acquaintance are familiar with it. So I do
not know if this works for all clays, or if it is a fortunate fluke of the
local soil.

I would appreciate hearing from anyone who might be interested in trying
this experiment.

Desmond Armstrong