procedural foliage spawner looks like having grid

[user_3efc87921bcb4110447d2e17e4d7044ea0722e55da9367bcdafdd8 (老子爱叫啥就叫啥)]

i use pfs to scatter my test trees, here is my pfs home page

but the resulting trees seem having grid obviously

anyone knows why? any help, thanks