Tuesday, October 1, 2013

Nut development: 1 Oct 2013

   Again this week I looked at the development of three pecan cultivars: Osage, an early-ripening cultivar; Kanza, a mid-season pecan; and Maramec, a late-ripening cultivar. As noted in yesterday's post on cultivars ripening since last week, Osage has completed the nut development process for the year by splitting open its shuck (photo at right).
    Kanza has filled it kernel and I found the very first indications that the shuck of this cultivar was starting to separate from the shell. In the photo at left, the red arrow points to the area where the shuck has started to separate from the shell. At this point, all you can see is a hairline crack between shuck and shell. Remember, that during shuck dehiscence, the process always begins at the nut's apex and works downward towards the base. The green arrow points to another indication that shuck separation has begun. The light tan spots near the tip of the nut are the very beginnings of black streaks normally found on the outside of the shell at harvest.

     I think that Maramec has largely completed kernel fill and you can see that this year's nut quality will be fair to poor (photo at right). The kernel has failed to press all the internal packing material up firmly against the inside of the shell and there are still air spaces near the kernel. You might also note that this Maramec nut is much smaller than normal which can be largely attributed to scab infection. At this point in time, Maramec is not showing any signs of shuck dehiscence. Will we harvest Maramec this fall? It will probably depend on when we get our first hard freeze this fall and if the scab infection will prevent shuck split.