New Hartford Tree Hangs On

New Hartford Tree Hangs On

In spring of 2010 Bartlett Tree (photo at right and below) assisted the CT Chapter TACF with pollinating a verified American chestnut located on the shores of West Hill Pond in New Hartford, CT. The nuts produced by the tree that summer were planted the following spring at the Great Mountain Forest back-cross orchard site. Today, the tree's progeny are growing along with the other four lines at this orchard with the expectation that they will be inoculated for selection in 2015, and intercrossed for placement in a breeding orchard sometime thereafter.

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Female Flowers with leaves cut back, pollinating with paint brush

Over the almost ten years of our efforts at finding and pollinating mother trees, Bartlett Tree played a huge role by assisting with accessing the often lofty flowers of the trees. Bartlett volunteered both time and equipment to the labor intensive practice of pre-flower bagging, pollinating and rebagging, and then harvesting the nuts for almost all of the trees in our backcross program. By doing so, they helped immeasurably with the success of the program. We quite simply could not have progressed without their dedicated support.

All too frequently flowering is a last gasp for our mother trees. Trees typically flower at no less than five to six years of age, and often not until much older. Since the blight fungus is prevalent virtually everywhere in the forests of CT, it is not if … but rather when … a Native American chestnut tree becomes infected. And once infected it is only a matter of time until most trees succumb. Many of our mother trees have incurred such extreme dieback by the season following flowering, that they have died within one or two years following back-cross breeding.

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Bags on Pollinated Tree

The pollen is overnighted from the TACF Research Facility in Meadowview, Virginia. The pollen – carefully stored – is kept in a small film vial (increasingly hard to find) with a small hole on top into which a paint brush can be inserted, to capture some pollen. The pollen is then transferred to the female flower, and once the flower is recovered with the protective bag, pollination is hopefully complete. The rest is up to nature and luck. The large inflorescence (seen in lower photo to right) is the male portion of the flower with the pollen. American chestnut trees are self-infertile, however, a tree within some distance (everyone seems to have a different idea of what that distance might be) might open pollinate the flower. Hence the need for the protective bagging.

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Examining a container with pollen

So it is surprising, and perhaps comforting to see a tree “hang in there” and survive for two or three years following the production of nuts. By the photo to the right you can see that it is still producing beautiful flowers (the showy male inflorescence and the female in the young ladies hand) and about 20-30 open pollinated nuts. This is significantly less than the 80+ it produced that season of intervention, but still enough to capture more genes and grow them in the garden. Will it survive and do the same next year? Each year the fungus reaches more of the cambium layer of the tree and makes survival less likely. Even now, perhaps two-thirds of the branches have dies from the effects of the fungus. So one of these years it will no longer show a flourish of life in the spring. We shall see!