C. Phenology. 



1. Patterns: Flowering begins in early August and usually peaks around the 

 third week. It may persist into early September barring frost or drought. The 

 onset of flowering in Montana is late relative to the rest of its range, with at 

 least one exception in that Idaho populations are later. Idaho populations 

 were just beginning to flower by mid August in 1997 when Montana 

 populations were in peak flowering (pers. obs.). 



Flowering has been found to vary significantly among individuals of an 

 occurrence (EO#001), with up to a four- week offset. In the early or late 

 portions of the flowering period, there are some plants in peak flower while 

 others are fully in bud or fiilly senesced, respectively. This staggered 

 flowering may be an adaptive phenological offset, or reflection of 

 microhabitat parameters unique for the individual plants. The great majority 

 of plants at this site appeared to reach peak flowering within a week of one 

 another. 



2. Relation to climate and microclimate: Flowering started in the first week 

 of August at least a week early in 1994 compared to the three following years. 

 The 1994 season had exceptionally high July temperatures and low rainfall 

 compared to the more average conditions of the following years. 



It is reported that the species sets its floral primordium when it forms an 

 overwintering rosette in fall (Arft 1995a). Flowering in other orchid species 

 is determined with the formation of the perennating bud the season prior to 

 anthesis. If this were the case, then a mild, long fall as occurred in 1996 may 

 correlate with high flowering stem numbers in 1997, and the high number of 

 flowering stems in 1994 may correspond vsdth the exceptionally wet, mild 

 1993 season. 



Conditions for seed set at the end of the growing season are also climate- 

 dependent. None of the mature capsules had dehisced to shed their seeds at 

 the time of monitoring on September 4 in 1997. Conditions rarely get drier 

 after this time for rupturing the capsule, so perhaps the capsules dehisce in 

 response to temperature. It is likely that the minute seeds have a very short 

 time to reach a safe site and become established before the growing season 

 comes to a close. Unshattered capsules were found at the monitoring site in 

 November long after the growing season ended. 



D. Reproductive ecology. 



1. Types of reproduction: Reproduction is sexual in the strict sense, though 

 each year's plant comes from a separate lateral bud. Most orchids produce 



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