scrub_oak has definitions from the field of botany
1
[ noun ] (botany) any of various chiefly American small shrubby oaks often a dominant form on thin dry soils sometimes forming dense thickets

Used in print

(Jim Berry Pearson, The Maxwell Land Grant....)

To the west of this road was another low bluff , forty or fifty feet high , covered with scrub_oak and other brush .

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