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Pelchat: SPIRANTHES PARKSII CORRELL – NAVASOTA LADIES’-TRESSES leading into woodlands and adjacent to the edge of woods along hiking trails the most plants were found within the woods on the banks of the natural drainage ditches. This observation confirms that Spiranthes parksii does not typically inhabit open areas or areas disturbed by man. Today S. parksii is well documented growing in the Navasota region and one especially good and accessible (because it is not private property) location is Lick Creek Park located in College Station. I have observed it growing in this park along the banks of drainage streams and at the mouth of these drainage areas leading from the open grassy areas of the Post Oak Savannah. I have also observed it growing on the margins of the wooded forest near drainage ditches where hiking trails have been formed. This habitat lies in close proximity to Texas A & M University and Dr. Hugh Wilson, from the University, undertook a detailed study of S. parksii. Unfortunately this study was brought to an abrupt halt by the expansion of a recreational bike path. Morphology The genus Spiranthes is highly variable from the morphological point of view and, at times, it is difficult to differentiate between species in the field. The problem of field identification is compounded for the species S. parksii because it blooms at the same time and in the same range as two other species, S. cernua (L.) L.C. Richard and S. lacera Raf. var. gracilis (Bigel.) Luer, and is found in similar habitat as S. cernua mixed in with blooming populations. However, once one establishes a pattern of identification there is no mistaking S. parksii for either S. cernua or S. lacera var. gracilis, though there are some plants that seem to be intermediate between S. parksii and S. cernua and these are not easily resolved in the field. While photographing these plants with a 105mm macro lens many of the characters described by Correll (Correll 1947 and 1950) are apparent. The line drawing by G. Dillon that accompanies Correll’s description is extremely accurate, and looks as if it was drawn form a live specimen rather then an herbarium sheet. 28
Pelchat: SPIRANTHES PARKSII CORRELL – NAVASOTA LADIES’-TRESSES The plants I have observed are from 21 cm to 25 cm tall with the flowers taking up the top 7 cm - 8 cm of the spike (Fig. 2). They are in 4 ranked coils of 14 to 30 flowers that spiral counterclockwise looking down on the top of the plant. The plants tend to have the flowers concentrated more at the top of the rachis twisting, generally, in a CCW direction forming 4 ranks giving the rachis a symmetrical appearance. In contrast S. lacera var. gracilis tends to have a single rank forming a long spiral to the top for most of the length of the rachis. There are no leaves present at anthesis, but I have observed the leaves of plants in the springtime and they form basal rosettes of 2 to 3 lance like elliptic shaped leaves (Fig. 7). It should be noted that I find the number, size and dimensions of leaves for Spiranthes spp. to be quite variable depending on the time of year observed, the amount of moisture present and apparently the amount of nutrients in the soil. Plants of S. vernalis grown in pots and fed high nitrogen fertilizer have produced over 8 large grass like leaves along with one large bract like leaf on the spike that have sustained through anthesis compared to the 4 to 5 often observed in the field. These observations suggest that identification of S. parksii based on vegetative characteristics of the rosettes is highly unlikely unless the plants were specifically marked while in bloom. The flowers and most of the rachis are covered in a fine pubescence, the apex of which is tipped with a ball or club. The same pubescence is found on S. cernua but S. lacera var. gracilis is essentially glabrous. The characteristically obovate petals, (Correll 1947), are also easily seen in the field through the lens of the camera or with a 10x loupe. The lip is presented in such away that the apex has a cleft and the center leading inward to the column is padded on each side and creamy yellow in color, (this coloring is also described by Catling & McIntosh 1979). The margins of the lip are ragged and tooth like or in botanical terms dentate compared to the crenulate (scalloped or round toothed) and undulate (wavy) appearance of S. cernua. Small pubescent 29
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