The Collaborative International Dictionary of English v.0.48:

Angustifoliate \An*gus`ti*fo"li*ate\
   ([a^]n*g[u^]s`t[i^]*f[=o]"l[i^]*[asl]t), Angustifolious
\An*gus`ti*fo"li*ous\ ([a^]n*g[u^]s`t[i^]*f[=o]"l[i^]*[u^]s), a.
   [L. angustus narrow (see Anguish) + folium leaf.] (Bot.)
   Having narrow leaves. --Wright.
   [1913 Webster]