I bought a ranch 5 yr's ago and wanted to put a lilac ranch on the property I found out a few months ago that the water table is at 96 inch and that if I planted and grove that I would get root rot and I could loose the grove is this true, what is the depth of there roots?
Among the moist touchy are raspberries yet I think the rule is that if the water table stays three feet below the surface they will grow.
What is the quality of the groundwater.....In southern California, wouldn't it be a tad high on the salinity? How does it vary over the year....is 96" the closest it gets to the surface? If so, you should be fine. Our water table in March & April is @ 36" before dropping (very quickly) over the summer. Lilacs do just fine here.