Thrips are important pests of dendrobium orchid flowers in Hawaii primarily because of the risk that exported flowers found to be infested will be rejected by quarantine inspectors. Using nondestructive sampling, the population dynamics of thrips infesting dendrobium orchids was monitored at two farms on the Island of Hawaii over a period of 1 yr. Average thrips populations varied between 0 and 1.0 thrips per spray (flower spike). At both sites, adult thrips almost always outnumbered nymphs. The western flower thrips, Frankliniella occidentalis (Pergande), was the predominant species found. Using randomization tests, adult thrips were found to be randomly distributed on orchid sprays. The binomial probability distribution was used to graphically describe the accuracy of scouting results as a function of sample size and the proportion of thrips-infested flowers. Efficient methods for counting adult thrips included nondestructive field counts (direct observation), flower shakes, and extractions via Berlese funnels.