I collected fruits from 22 ocotillos (Fouquieria splendens) at two sites in the northern reaches of the Chihuahuan Desert in southern New Mexico for four consecutive years (2005-2008) to measure reproductive output. Individual ocotillos produced an average of 332-2,252 fruits per year. More than 95,200 fruits were produced by all 22 plants combined during the study, an average of more than 1,080 fruits per plant per year. Plant size, as represented by the number of stems ≥1 m in length, was significantly related to fruit production (R~2 = 0.465, P < 0.001). Individual plant-to-plant variation combined with year-to-year variation accounted for 57% (P < 0.001) of the variance in fruit production, yet the contribution from year-to-year variation alone was not statistically significant (P = 0.127). Mean seed density varied from 10.3 to 11.6 seeds per fruit at the two sites in a 2001 analysis. Seed density estimates from these data and three additional sources applied to my fruit production data resulted in a conservative estimate of over 666,000 seeds produced during this study by the 22 ocotillos. These reproductive output data describe a species whose strategy for survival is to annually disperse high numbers of individually low-cost propagules to increase the probability that at least some will be available to germinate and survive in response to the rare occasions when requirements for germination and survival are met. That the prodigious production of fruits in ocotillo was not evenly distributed across sites, years, or individuals provides new insights into this iconic species considered to be one of the most unique and widely distributed plants in the deserts of North America.
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