Same here. In eastern Pembroke Pines, it looks like I have immokalee fine sand which is flatwoods soil. The sapodilla and mango has it's roots within the top black organic layer and hardly any roots within with thick white layer. I've dug 3 feet down and still get white sand. I guess since that layer tends to dry out quickly and has very little nutrients, the roots seem to avoid it even though it is very soft. Flood insurance is also not required where I live either, which makes sense, since it hardly ever floods unless it downpours for very long periods of time. Out of the 12 years I've been living here, I've seen the low area of my back yard remain flooded for about two hours before draining away.