Excitation of two nuclear spin waves, as predicted by Hinderks and Richards, has been accomplished by parallel pumping in CsMnF3at 988 MHz. This is the first time to our knowledge nuclear spin waves of nonzero wavevector have been excited directly by electromagnetic fields without simultaneous excitation of electronic spin waves or other modes. Wavevectorskfrom near zero to 105cm−1are excited at 4.2° and 1.1°K. Relaxation times are sufficiently long that they can be measured directly from the transient decay, without having to rely on absolute measurement of criticalrffields. Order of magnitude or better agreement is obtained with the theory of Richards on the relaxation rate &eegr;kalthough thekdependence does not agree at 4.2°K. At 1.1°K, thekdependence is very close to that predicted by theory. The values of &eegr;kat 4.2°K are very close to those inferred by Seavey from more indirect measurements. A second threshold has also been detected at higher powers. This may be the result of nuclear spin and lattice heating which causes first an increase and then a decrease in the nuclear spin‐wave frequency.