So
many trees in our landscapes require a dry environment under them.
Finding plants that will thrive in a dry shade garden can be
difficult. Most of what is found in garden centers lusts for
water. Appropriate planting under oak trees is critical if we are to
maintain our natural oak forest.
This dry shade garden list
includes both natives and introduced landscape plants that will thrive on the conditions
that are ideal for planting under our native Coast Live Oaks, Quercus agrifolia. We so often plant
these areas with lawns, azaleas, fuchsias and many other water loving plants.
In the long run this is no good for the oak trees. The
oaks may not show stress immediately but over 10-20 years it can spell disaster.
The extra irrigation coupled with the fertilizing in the area of the trees with
ammonia based fertilizers destroys the native soil fungi. This
creates conditions ideal for the oak root fungus to get a foothold. While oak
trees can grow in wet conditions (I have seen old trees growing in creek bottoms with
water running over the roots all year) they can not take a change of diet without extreme
risk of death. The problem zone extends to the drip line of the tree and somewhat
beyond. This means the entire area shaded by the tree and probably half again
that
radius of the tree has roots from that tree. Any change of grade or increase in the
irrigation within this zone compromises the tree.
Two great books on this theme are listed below.
