The OSCAR system was designed for shallow soil conditions and/or limited area. Some lots could not be developed unless an OSCAR system was used. But how to make them look appealing?
The options for landscaping the OSCAR vary according the owners tastes. They can be left in a natural state where native plants such as ferns, salmon berries, and grasses take over. Or, they can be planted with lawns (hydro seeded or sod), shrubs, ornamentals, and trees.
There are two things that must NOT be done when landscaping: 1. do not plant trees in the coil area directly on top of the OSCAR, and 2. do not cover the coil area with high organic, composted top soils. As the trees grow they could physically damage the coils as the tree trunk expands, and the high organic top soil absorbs water that would have evaporated from the top of the OSCAR. The top soil holds the water and gives the appearance that something is wrong.
When an OSCAR system is first installed the cover sand has little to no structure. Walking on it leaves footprints and the sides slough very easily. But this will not always be the case. When the system is put into operation, the coils will automatically “water settle” the sand and it will become firm. The OSCAR is subsurface irrigated. The sand will grow anything that is planted in it. As plants begin to take root, the root mass holds the sand in place. Many OSCAR system that are covered with grass can be mowed with a push mower without the sand sloughing. It may take a growing season or two for the lawn to fill in completely..
Some other options for covering are beauty bark or 2-3 inches of soil. The sides of the OSCAR can be covered with soil to blend the OSCAR into the surrounding contours.
In areas with high winds (the top of ridges in the Vantage or Yakima areas) it may be necessary to cover the OSCARs with soil, about 6”. The wind drys out the sand very quickly and then carries the sand away. This is an extreme condition and does not occur very often.
Below you can view some before and after photos of OSCAR systems. These are included to give the property owner a concept of what the OSCAR will look like after some time passes.
OSCAR system for Bald Eagle Golf Course, Point Roberts, WA