Grafting Pecan Trees in South Central PA, Part 3 of 3
Posted: April 17, 2012
This is the third of three articles on Grafting Pecan Trees, focusing on variety selection.
http://aggie-horticulture.tamu.edu/carya/pecans/cvintro.htm is the link to the Texas A&M University and USDA treatise on pecan varieties.
It lists some 150 varieties with detailed history and characteristics. This article and my focus as well as my offer to graft for the reader, will focus on two, Kanza and Pawnee.
From the TAMU referenced above:
'Kanza' Orig. from a controlled cross ('Major' X 'Shoshoni') made in Brownwood, TX by L. D. Romberg. Nut: ovate, with an acute apex and obtuse to rounded base; round in cross section; 77 nuts/lb, 54% kernel; kernels golden in color, with dorsal grooves that do not trap packing material. Released for its ability to produce good yields of high quality nuts in the northern pecan producing regions (Zone 6b). Protogynous, with late pollen shed and early pistil late receptivity. Kanza has excellent scab resistance.
'Pawnee' Orig. by controlled cross ('Mohawk' X 'Starking Hardy Giant') made by L. D. Romberg, USDA-ARS, Brownwood, TX. Released in 1984 to be grown throughout the U.S. pecan belt. Nut: elliptical with obtuse apex and rounded base; laterally compressed in cross section; 44 nuts/lb, 58% kernel; kernels golden in color, with wide dorsal grooves and deep basal cleft. Protandrous, with early to mid-season pollen shed and mid- to late season receptivity. Precocity and production medium, with some tendency to biennial bearing. Nut matures early, latter half of September in Brownwood, TX. Medium susceptibility to scab, fair resistance to downy spot, outstanding resistance to yellow aphids. Recommended (1990) for planting across TX, OK, KS, to AL and AR.
I selected these two varieties for several reasons. Kanza is Protogynous (Type 2). What does that mean? From the internet search: Protogynous
▶adjective Botany & Zoology (of a hermaphrodite flower or animal) having the female reproductive organs come to maturity before the male. The opposite of Protandrous.
Note that Pawnee is Protandrous (Type 1), opposite of Protogynous. Simply put, it means that they can pollinate each other!
About 12 years ago I made a mistake in ordering 3 pecan trees of the same variety, Pawnee. I was thinking it took two trees to pollinate each other. Necessary but not sufficient! Two trees of opposite type (Type I vs. Type II) are needed to pollinate each other! There are several large mature pecan trees growing in Adams County, many years old that do not produce pecans. The principle reason is they do not have a suitable pollinator. In the last 10 years, as I became more knowledgeable, I figured out that if I took a small limb piece in bloom from another tree luckily of a different type, with the male blooming catkin, and attached it to my Pawnee tree in Carroll Valley, the breezes would do the deed for me. Olay! I got 15 pecans from my young Pawnee pecan tree!
Having covered the vital issue of pollination, the other factors were hardiness in our zone, scab (fungus) resistance (its wetter here than in Texas and Kansas) and nut attractiveness (size and ease of cracking the nut).
Pawnee does not score high in a couple of our goals, like alternate bearing tendency and medium susceptibility to scab, but there are not ideal alternatives in the Type I inventory, so it’s the best among poor choices. I made the judgment that if they produce in Kansas, they will probably produce here, and they do.
Let me repeat my pecan offers here. Send an email to Devlinw1@aol.com and I will set aside some pecan seedlings for planting July or early August. If you have already grown seedlings from me, I will schedule grafting for mid-May.
The Penn State Master Gardener Hotline to answer gardening questions is open April through September, on Mondays and Fridays, from 10 am to 2 pm. Call 717-334-6271 or bring in your samples for a diagnosis to 670 Old Harrisburg Rd, Gettysburg.
Bill Devlin is a Penn State Extension Master Gardeners from Adams County. Penn State Cooperative Extension of Adams County is located at 670 Old Harrisburg Road, Suite 204, Gettysburg. Call 334-6271.