Nut expansion begins for early ripening pecan cultivars
Earlier this week I collected some nut samples from 3 pecan cultivars. The first tree I visited was a Henning, one of the earliest ripening pecan cultivars we have in our collection. I then cut nut clusters from a mid-season ripening Kanza tree and a late-ripening Maramec tree. At this point in the growing season, you can see that Hennnig nuts have already started to plump-up and have entered the phase of rapid fruit expansion (photo above). Kanza and Maramec still looked to still be in the post-fertilization phase; just waiting around to start fruit expansion.
Cross sections of a Henning, Kanza, and Maramec nuts (left to right)
Cutting into the nuts confirmed my suspicions about the stage of nut development for each of these cultivars (photo at left). The cotyledon of the Henning nut has expanded into a large heart shape; the first indicator that the nut has started into rapid fruit expansion. In contrast, the Kanza and Maramec nuts had small oval-shaped cotyledons. Rapid fruit growth for these two later-ripening cultivars has not yet begun.