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Mortality of cacti after grassland fires is usually < 25% within 2 years. Little, however, is known about long-term mortality. This study followed the fate of 50 marked plants of each of four species of small cacti (Coryphantha vivipara, Echinocereus pectinatus, Echinomastus intertextus and Mammillaria heyderi) on burnt and unburnt desert-grassland in Arizona. All marked plants were dead within 16 years. The first three species suffered increased mortality after being burnt while M. gummifera survived better after fire. The average rate of mortality of burnt plants over unburnt plants was 10.2 times higher in E. pectinatus, 3.7 times in C. vivipara and 1.5 times in E. intertextus. In M. heyderi, however, the mortality of burnt plants was 0.25 that of control plants. Fire more rapidly removed the breeding populations of the first three species, reducing seed availability in the occasional years favourable for establishment, increasing the risk of local extinction. Cacti did establish on the study areas and by the end were of a similar size to the dead cohort giving the superficial impression that the site was unchanged except for a reduction on unburnt sites in total cactus density (burnt: 445/ha in 1987, 401/ha in 2003; control: 2235/ha and 675/ha, respectively). Evidence of fire and dead plants rapidly disappeared, so without plants being marked the death of one population and establishment of another would have been easily missed. Estimates of growth rates support the assertion that the final plants established during the study.