An important question is when does selection occur in the ontogeny of the plant. Studies of seedling germination and subsequent development in nature may allow us to address this. Our results disagree with Curtis' views concerning habitat and lack of specificity. However, his assertion that the symbionts found will vary depending on the environmental variables of the site is borne out by our data. As shown in Figure 3, there were strong geographic patterns in the distributions of symbiont types.
Some patterns appear very localized, while others are widespread.
For example, type M was found only once, in Wildcat Regional Park, while all six other individuals sampled in the park contained type D. Type C was notably found only in sites above 6000 feet elevation. It was also the only type found in these sites. Most Corallorhiza plants were found growing under mature conifers, particularly Pseudotsuga menziesii, and a variety of symbionts occurred in these sites. Every sample of Corallorhiza maculata collected under pure or mixed stands of Quercus was associated only with type D. Type D was not found in any other sites. We have solid evidence that seasonal changes in symbiont identity does not occur in Corallorhiza maculata .