Pecan


#443

I got nine more grafts put on for 3 more varieties of pecan. Hark, Dooley, and Waco Wonder are now on trees and ready to grow. I’m about to sharpen my grafting knife. Hark was tough whittling which is consistent with having Major for a parent.


#444

I collected a stick of greenwood off one of my young pecan trees today and am about to go out and set a few coin purse buds on some young trees. I have had about 50 to 60 percent takes with greenwood buds in the past. The buds must be large and mature and have a leaf rachis still attached. Make a vertical slice about 3 inches long on last year’s bark of a young seedling and push the bark back from the stem bending the tree slightly to make it open up like a coin purse. Slice the bud off the green stick with a sharp knife so that 2 to 3 inches of stem tissue is retained. Leave the woody part in the bud and leave the leaf rachis attached. Cut the rachis off so that 2 or 3 pairs of leaflets are left. Insert the bud into the coin purse on the stock by bending the tree slightly to open up the gap. When the bud is positioned, wrap the bud with grafting tape (or electrical tape). Wrap a piece of plastic such as from a ziploc bag around the bud forming the leaflets slightly around the stem and tape - with masking tape - the plastic into a loose sleeve with about an inch of space around the bud. The leaflets collect enough sunlight to encourage the tree to heal the wound and accept the bud. If set early enough, the bud can be forced in July or August with a few inches of growth the year it is made. If set later, the bud can be forced next spring.


#445

It’s good to force it in zone 5-6 next year. Not recommended to force it unless in a zone like yours.

Interesting technique for younger stock, Darrel.

Dax


#446

Yesterday I regrafted some of the grafts that were killed by the June 10th freeze. I grafted Hark, Kanza, Pawnee, Carlson 3, Norton and Dumbell Lake. It hit 96 today, the first 90 of the season, about a month late. I may have a few more to do in the next few days if the older grafts do not respond to the heat.

After that will work on greenwood grafting and budding. I had nine trees, some grafts and seedings, killed to the ground by an early fall frost. Now they have sprouted vigorously from the ground and will use them for "experimenting with greenwood grafting and budding.


#447

I put in a couple of hours today filling pots and setting seedling pecans into them. I have about 40 done so far and prepared potting mix to pot up another 25 tomorrow.

It is critically important to keep pecans in containers well watered. I let a tray of three go dry. Two days in the greenhouse with all day sun turned 2 of the seedlings into crispy black stems. Do NOT let seedlings get dry. I’ve got all seedlings on a daily water schedule now.

I also learned that Kanza nuts must be planted on their side. I planted a bunch of them by pushing them sharp tip first into potting soil in 6 inch deep cups. A few of the seedlings germinated and pushed a root down but the tip that should have grown upward was trapped between the seed cotyledons. This seriously delayed or prevented emergence of several seedlings. For general caution, it is probably best to ensure pecans are on their side when germinating.

Notes and logistics for future reference. I paid about $3 per pot from Stuewe including shipping. Each pot takes about 4 gallons of promix BX at a cost of about $2 per pot. The end result is that each seedling I produce will have a base cost of $5. I have to add my time watering and caring for the seedlings.

Why am I using Promix BX? I want to be able to sell these seedlings so they have to be disease and pest free. The only way to ensure seedlings are not infested with nematodes is to grow them in sterile seed start mix.


#448

Just a tip for all seed future reference: if the seed were to be dropped from your hand onto the ground and how it lands and stays put is how nature intended for the seed to grow.

Dax


#449

My guess would be that most seedling pecans start from being buried by an animal and forgotten. I suppose that would still leave the seed pecans lying on their side or close to it. You would think the sharp point of the pecan should have some evolutionary purpose that would help with germination or maybe the design is just about strength of the shell. Impressive output Fusion, as always.


#450

https://etd.auburn.edu/bitstream/handle/10415/6073/Dissertation final copy.pdf

As I noted several posts above, Adams#5 is protandrous here in northwest Alabama. However, catkin length suggests it may be protogynous at other locations. Heterodichogamy is complex with number of days below 45F during winter interacting with number of days above 72F and number of nights above 60F in spring to determine flowering dates. A variety has a genetically determined chilling hour requirement before it will break buds in spring. This does not work the same as with other fruit species in that high spring temps will break dormancy in pecan albeit delayed as compared with trees that met their chilling hour requirements. Stuart has chilling hour requirements of about 500 hours where Elliott requires about 300 hours. Dodd requires closer to 600 chilling hours.

Male and female flower buds have different chilling/heating hour requirements on a given variety. A normal winter here in North Alabama provides about 700 chilling hours. Under these conditions, catkin development may be shifted later in the season where pistillate flowers are produced earlier as compared with a location in South Alabama.


#451

Reading through the details of this analysis of scab susceptibility across the pecan genome, I was struck by one significant fact. Sampling error was a significant issue. This means that human error in terms of the person collecting the data was highly relevant to the final analysis. How can I tell? Look at the disparity between 2013 and 2014 data with the knowledge that 2013 had quite a bit more rainfall. I would expect a given provenance to show significantly more scab in 2013, yet what I see is an equalization of results in 2014 such that the data can’t be readily aligned with 2013 results.

https://apsjournals.apsnet.org/doi/pdfplus/10.1094/PDIS-12-15-1398-RE

I’m going to speculate re the number of scab resistance genes in pecan. I think the number of genes is very high, perhaps in the range of 40 or so with many of them recessive and very few dominant. Why so many? Because the crossing data I’ve seen and the results of breeding efforts that have been published give too many inconsistent results to have lower numbers.

As a comparison, late blight is a highly infectious disease that affects potato. A quick screen of literature shows 14 identified resistance genes with a few more that have been posited. Yet breeding results with potato are fairly predictable in terms of number of offspring inheriting resistance and which specific late blight strains will be stymied by a given set of R genes. If you want to read about this, search for Sarpo Mira and potato R genes.


#452

This article Monte Nesbitt wrote re herbicides in pecans is worth a read through.

I’m busy tending grafts and working in the garden. Today I checked the 3 coin purse buds I put in a week ago. All three failed. I kind of expected this since they were put on about 3 or 4 weeks too early. The buds selected must be mature yet still have an attached green leaf rachis. The buds were not mature enough. I’ll wait another week or two and try again.


#453

I have 90 seedlings potted up in the greenhouse. Another 25 seedlings have emerged and will be ready to pot up in a few days. A quick check of the trays showed at least 50 more germinated nuts with a root growing. I expect to have between 150 and 200 seedlings by the end of the season. These are roughly 2/3 Kanza and 1/3 Adams #5.


#454

Very nice, Darrel. What do you plan on selling them for? Curious how long they will be in the large pots you’re using and how large they’ll be when saleable?

Dax


#455

I spoke with Wes Rice before getting these pots. He used TP616 pots and says seedlings can be kept in them up to 2 years which means they can grow for one summer after grafting. I am using TP818’s which are significantly larger than the 616’s. I am also using a different method of root pruning. I will post about it after verifying that it works.

I have not made up my mind about price when selling them. As noted above, my costs are about $5 per seedling. If I were selling them as seedlings, I’d probably double that to $10. This is obviously higher than most people want to pay for a seedling. They should be worth about $30 to $40 grafted with a good variety on top. By that time, I will have 2 years into growing them so my cost basis will be between $10 and $15 each.


#456

I never heard you mention you were grafting on them and I could never figure that out. Now it’s becoming more clear.

Dax


#457

Well, considering that the nuts just germinated, it is not set in stone what I will be doing with them. I would be perfectly happy growing enough seedlings to set out a hundred or so on my land. If I can grow and graft my own trees, I can cut the cost to establish per acre to less than $200.


#458

I hear you talk about Adam’s #5 quite a lot. Is that your favorite down there in AR? I never heard of it until you said something about it.

Dax


#459

It is not my favorite, but it is a very good pecan and a relatively carefree tree. I can’t really say that I have a favorite. If it makes pecans with little or no care on my part and they taste good, I like it.

Adams #5 is a relatively vigorous and productive tree with extremely good scab resistance. The nuts are small and it is somewhat susceptible to black aphids. Based on bud break this past spring, I think it will grow and produce up to at least Kentucky. It is an outstandingly good yard tree. Size precludes commercial use. If this level of scab resistance were in a Desirable size pecan, it would be the most planted variety in the U.S.

These pictures were taken in 2017. The tree is now over 6 inches diameter with a good crop of nuts.

Adams #5 tree, nearly 30 ft tall, cleft graft 6 ft up on a healthy rootstock in 2012 http://www.selectedplants.com/miscan/DSC01339.JPG

Adams #5 nuts with no sign of scab http://www.selectedplants.com/miscan/DSC01340.JPG

Adams #5 limb with no nut cluster showing leaf/rachis growth http://www.selectedplants.com/miscan/DSC01341.JPG

Adams #5 showing a nut cluster slightly out of focus and 5" diameter trunk with wide branch angles http://www.selectedplants.com/miscan/DSC01342.JPG

Amling inset bud graft made June 22nd 2017 showing pale green color typical of a newly growing graft of this variety. This tree is over 12 feet tall now. http://www.selectedplants.com/miscan/DSC01343.JPG


#460

That’s pretty amazing how scab free it is.

You have nice turf.

Dax


#461

I did graft checks today. 2/3 of pecan grafts made a month ago were accepted. A persian walnut graft took but a black walnut failed. As you well know, it ain’t over until the graft is growing vigorously.


#462

Grafted pecans here at the house have started bearing in the past few years… it’s a battle with the crows for the nuts… but I’m beginning to find seedlings popping up all over the yard/orchard area, courtesy of the crows/jays dropping themas they fly off with them…mowed around at least a dozen the other day. I’m pretty sure they’ve just germinated in whatever orientation they hit the ground and settled into the grass and leaves.