Assertion: owl's expansion | /r/HasProperty | westward
Facets:
Source sentences:
text: By far the most controversial aspect of the barred owls current state is, upon their westward expansion, their encroachment of the range of their cousin, the threatened spotted owl (Strix occidentalis).
text: In general the reforestation at the northern sections of the Great Plains have, on the contrary, benefited barred owls (and may have been a part of allowing their westward expansion) and been perhaps slightly detrimental to the great horned owl.