The unusual glassy dynamics exhibited by the spin fluctuations in
the stripe-ordered cuprates can be quantitatively measured by La
nuclear magnetic resonance. We analyze the spin lattice
relaxation data in the low temperature tetragonal structural phase
of La<sub>1.8-x</sub>Eu<sub>0.2</sub>Sr<sub>x</sub>CuO<sub>4</sub> and find that there is a distribution of local fluctuations times, with a Vogel-Fulcher temperature dependence. Furthermore, the data are consistent with a stretched exponential form for the dynamical spin correlation function, typical of glassy systems.