A series of photos taken by Dr. Fred Hebard detailing various stages of female flower development in chestnut.
Immature Female 1
Female bur too early to bag
Immature Female 2
Female bur too early to bag
Immature Female 3 Closeup
Closeup of a female bur, too early to bag.
Almost Ready to Bag
Styles are out, there are 3 florets. This female flower is almost ready to bag.
Almost Ready to Bag 2
Closeup of a female chestnut flower almost ready to bag. The styles are almost out but have not yet emerged. The numbers designate the 3 florets visible on the flower.
Bur Ready to Bag
The styles have emerged on this female flower, and it is ready to bag.
Bur Ready to Bag 2
Closeup of a female chestnut bur flower ready to bag. The styles have just emerged and as are the anthers on the male flowers (catkins).
Almost too old to bag
These female flowers may have already been contaminated by other undesirable pollen. The styles are fully emerged. If the cross is highly desirable, it may be worth going ahead and bagging, but using a higher number of control bags to measure contamination of the cross.
Almost too old to bag 2
These female flowers may have already been contaminated by other undesirable pollen. The styles are fully emerged. If the cross is highly desirable, it may be worth going ahead and bagging, but using a higher number of control bags to measure contamination of the cross.
Bur past bagging
This female flower is too old for bagging, but too young to pollinate. It will likely be fruitless to bag at this stage. Try again next year!
Bur past bagging 2
This female flower is too old for bagging, but too young to pollinate. The styles are long and spreading apart. It will likely be fruitless to bag at this stage. Try again next year!
Ready to pollinate
This female flower is at peak receptivity and ready to pollinate. As long as the bagging timing was correct, this takes place about 10-14 days after bagging.
Ready to pollinate 2
The female flower on the left is at peak receptivity and ready to pollinate. As long as the bagging timing was correct, this takes place about 10-14 days after bagging. The female flower on the right is still a bit too young for pollination. To achieve maximum seed set, one would want to return to the tree in 2-4 days and re-pollinate; but that's not always possible.
Catkin over Bur
A male catkin being held over a female bur.
Catkin development
Sometimes - though not always - catkin development can be used to gauge readiness of female flowers. Here, the top catkin is "not bushy" (anthers/pollen not out), which generally indicates the female flower is not ready for pollination. The bottom catkin is "bushy" (anthers/pollen out), which is generally an indication the female flower is receptive for pollination.
Catkin development 2
Sometimes - though not always - catkin development can be used to gauge readiness of female flowers. Here, the top catkin is "not bushy" (anthers/pollen not out), which generally indicates the female flower is not ready for pollination. The bottom catkin is "bushy" (anthers/pollen out), which is generally an indication the female flower is receptive for pollination.
Too Late
This is an over-mature bur far past receptivity for bagging or pollinating. The catkins have turned brown and most anthers/pollen has already shed.
