Gardner pistillate flowers |
It looks like we are about half way through the pollination season. The pistillate flowers of protogynous cultivars, like Kanza, appear to be pollinated (photo at left). The tips of the female's stigmas turn black in color after they have received pollen.
Protandrous cultivars have either shed all their pollen and dropped their catkins or are releasing pollen grains now. The photo at right shows the catkins of Yates 68. The center cluster of catkins has released its pollen and is starting to turn brown. The catkin clusters to the right and left are yellow in color indicating that the pollen sacs are fully mature and ready to burst open.
KT149 is protandrous and has showy red stigmas much like its Pawnee parent (photo at left). Kanza is protogynous and produces pistillate flowers that are smaller with yellow-green stigmas. The color of pecan stigmas can range from green to yellow to orange to red and is not related to flowering type. However, the size of the stigmas found on protandrous cultivars always seems much larger in comparison to the stigmas found on protogynous cultivars.
Most growers look forward to pollination season because they get their first glimpse into next fall's nut crop. Remember, the number of catkins produced by a tree is not related to nut load. Look for pistillate flower clusters as they emerge from the tips of this Spring's new growth (circled in photo at right). A full nut crop is produced when 50-70% of all new shoots are terminated by a pistillate flower cluster.