Thursday, May 28, 2015

2015 Grafting season is winding down

Szego chestnuts.  Picture from HERE.  If you know anything about chestnuts you know that these are big, honking chestnuts!
I finished grafting the Szego Chestnut scion wood.  Michael Nave, a Chestnut guru who lives in Elverta, California (near Sacramento) claims that Szego is an eager grafter and is not fussy about bonding to a wide variety of rootstock.   I think he is correct.  My grafting success with Szego is as good as my grafting percentage is with apples.

Lucky Pittman claims that grafts knit together from the top down.  It is entirely reasonable to believe that some varieties might store larger amounts of carbohydrates and to callous under less than optimum conditions than other cultivars.  I started following Lucky's advice to use a fairly long scion piece (6 inches or so) on difficult-to-graft species to ensure the top has sufficient resources.  Since I started doing that my percentage of takes took a big jump upwards.  Before listening to Lucky I was trying to squeeze the maximum number of grafts out of my scion wood and my pieces were often 2 inches long or less.

I am also experimenting with some tree tubes that were gifted to me.  Chestnut grafts seem to really like tree tubes.  They are not something I would have bought as they are pretty spendy at almost $3 a piece.   It is warmer in there and the emerging shoot is less exposed to the desiccating  effects of the wind and sun.  I believe that I will be recycling these tree tubes over-and-over.  They become much more cost effective if you can get multiple uses out of them. 

Wuldumar Nature Center.
The trees on the left side of this photo are Persimmon trees (Diospyros virginiana).  Somebody planted a persimmon seedling beside their main building about thirty years ago and it formed a thicket.  It was a male persimmon.  That probably worked out because the trees canopy over the handicapper access ramp and fruit would make a slippery mess.

There has been so much personnel turn-over in the last thirty years that they had no clue regarding the species of tree.

I called them up and offered to graft some "Lena" (a female) onto some of the suckers.

The current director thought that was OK.  I was doing it for free and one of their star volunteers is named Lena.  He thought she would get a big kick out of that.

Nature centers can be tricky places to do guerrilla gardening.  Depending on the language in their charter,  cutting a twig the size of a match stick can almost require an act of Congress.  It is my impression that Wuldumar has one of those highly restrictive charters.  As a "tree guy" the place is over-run with junky and invasive species.  I made six grafts and they will probably hang on but they will not thrive until somebody trims the Box Elders that are shading them.  Maybe Lena can nudge those Box Elders.

Black Walnuts

None of the Davidson grafts took.  The Hay #1 grafts are pushing so I doubt it was technique or aftercare.  I think I had dead scion wood.

I have a dilemma.  I can either regraft with my unvalidated "Sparrow" scion wood or I can wait a year and try to get more "Davidson" scion wood.  Most likely I will split the difference.  I will graft until June 1st and then I will hang up my grafting knife until budding season.  However many trees I get by then is how many I will get.

1 comment:

  1. Joe,
    Some years back, someone...I don't recall whom, but I suppose I trust their knowledge base implicitly... probably someone with some plant physiology background... don't think it was Shigo...stated that callusing initiates from the scion - and if you think about it...auxins, produced in apical locations do have something of a modulating effect...
    One of the things one of my grafting mentors recommended - particularly for 3 or 4-flap 'banana' grafts on pecan/walnut/hickory, was to make a couple of near-circumferential 'girdling' cuts in the bark below the graft union (not removing a strip of bark, just cutting it. Purpose is twofold - allows for some sap leakage and diminishes flooding out of graft, while concentrating auxins in the portion above the girdling cuts, at least until the knife-cuts heal.