Abstract Yellow-poplar seed-heads can be collected successfully by shaking using a standard Shock Wave Shaker. In the first year of this trial the average percentage shaken was 64 per tree, varying from a low of 24 to a high of 95. Average percent shaken dropped to 49 per tree the second and third years, with a range from 9 to 90%. Shaking causes superficial damage only and will not affect subsequent crops. There seemed to be no effect due to tree size, seed-head size, or shaking time. Pre-collection estimates of numbers of seed-heads using field glasses to aid in counting were only minimally successful. North. J. Appl. For. 4:78-81, June 1987.