05-12-2008, 03:59 AM
I don't know the basic rule, but more people have pahoehoe and we have a'a rubble in most of Seaview. You can use a pickaxe to make a decent sized hole and about a foot down is a more cindery "soil." Of the several trees I planted before I moved here (hence no water other than rain) none of them died over 3 years.