  Background: Clustering phenomena in $N \neq Z$ nuclei provide an opportunity
to understand the interplay between cluster and nucleon degrees of freedom.
  Purpose:To study resonances in the $^{18}$O spectrum, populated in
$^{14}$C+$\alpha$ elastic scattering.
  Method: The Thick Target Inverse Kinematics (TTIK) technique was used to
measure the excitation function for the $^{14}$C+$\alpha$ elastic scattering. A
42 MeV $^{14}$C beam was used to populate states of excitation energy up to
14.9 MeV in $^{18}$O. The analysis was performed using a multi-level,
multi-channel R-Matrix approach.
  Results: Detailed spectroscopic information, including spin-parities, partial
$\alpha$- and neutron- decay widths and dimensionless reduced widths, was
obtained for excited states in $^{18}$O between 8 and 14.9 MeV in excitation
energy. Cluster-Nucleon Configuration Interaction Model calculations of the
same quantities are performed and compared to the experimental results.
  Conclusions: Strong fragmentation of large $\alpha$-cluster strengths is
observed in the spectrum of $^{18}$O making the $\alpha$-cluster structure of
$^{18}$O quite different from the pattern of known quasi-rotational bands of
alternating parity that are characteristic of $N=Z$, even-even nuclei like
$^{16}$O and $^{20}$Ne.
