Chaptalia texana Peduncles at Dispersal
by Bob Harms
Peduncle Length at Dispersal
Peduncles were collected and measured when a large number of heads were at the dispersal stage. Overall the open–head type had the longest peduncles and the populations in relatively more shaded areas above Deadman's Creek (Type II) the shortest. Soil moisture and exposure varied considerably, but did not seem to be a factor.
Type | Number | Range | Average |
Open–Head Bloom | 46 | 20–46 cm | 33 cm |
Closed–Head Bloom with Apparent Ligules | 56 | 5–27 cm | 14 cm |
Closed–Head Bloom with Greatly Reduced Ligules | 53 | 9–34 cm | 24 cm |
Angle of Head Relative to Peduncle
At dispersal the peduncles with few exceptions were straight and erect, bowing, if at all, only at the very apex. The angle of the bend was measured by plotting a line at a right angle to the receptacle against the upper straight portion of the peduncle.
Type I heads exhibited the greatest amount of nod, a number exceeding 90° — and none were fully erect, 0°. Type II and III heads never reached 90°, and a number of each type were fully erect.
- Open–Head Type
-
Closed–Head Type with Apparent Ligules
- Closed–Head Type with Greatly Reduced Ligules
Plant Resources Center Home Page — Flora of Texas
— Chaptalia texana