|Dollar bill added for size reference. These cuttings are BIG.|
I planted them on 14" centers in rows that are 42" apart (350mm in row by 1.05m between rows). Mr Internet suggested 12" and 36" for maximum straightness. More distance should increase girth at the expense of some straightness. You pays your money and you takes your chances.
|Apologies for the muddy picture. A ten inch cutting with 8 inches in the ground and 2 inches above ground. (250mm long, 200mm in the ground and 50mm above ground.)|
I am flabbergasted by the outstanding customer service I received from the National Resources Conservation Service (part of the United States Department of Agriculture).
I had emailed one of the agricultural research stations requesting information about the availability of certain elite selections of Black Locust (Robinia pseudoacacia). They emailed back that they had nothing available at the moment but that they might be able to help me if I could be patient.
Somewhere along the line, a scientist named Shawn Belt at the Beltsville, Md station decided to make getting me some root cuttings of the Steiner group Black Locust one of his personal missions. My home-run scenario involved getting nine root cuttings....three each of Algonquin, Allegheny and Appalachian cultivars.
Shawn Belt blew me away with his generosity. I ended up with 75 root cuttings.
---Background---Outside of the United States, in countries like Hungary, the Black Locust is considered an miracle tree. It fixes nitrogen, i.e. makes its own fertilizer so it grows faster than blue-blazes. "Ship-mast" tree forms have been selected for straight, knot-free trunks. The wood is hard, tough and incredibly rot-resistant. And the blossoms produce prodigious amounts of nectar for honeybees.
Adaptation in the United States has been slowed by the large numbers of pests that are endemic to the area. Most specifically, borers. Locust borers result in Dr Seussian trees with random, scraggly bends. They are the quintessential Halloween-spooky looking trees
Scientists noticed large amounts of variation in scraggliness, even in areas with heavy borer pressure. They made selections of the straightest trees and had a horse race. The Steiner Group of elite Black Locust were the winners.
It begs the question, if Black Locust is a miracle tree, and if Steiner selections overcome the problems with the borers...why are they so hard to come by?
The problem is that propagating Black Locust clones is very labor intensive. They are propagated from root cuttings.
Roots are harvested from adolescent trees by chisel plowing, running subsoilers or hand digging to bring roots to the surface. The roots are cut into 6 inch (150mm) long sections and individually potted up.
|The bundle of roots from Algonquin Black Locust as shipped from NRCS, Beltsville.|
|Broken down into cuttings. It is critical to have some way to mark the end that was away from the trunk. As advised by the protocol I was given, I used diagonal cuts on the basal end.|
|A close-up of the pot before I top it off with local, garden soil (Marlatt Loam)|
It will be a merry mess trying to split these pots of eight trees apart, but these pots were the only ones I had that were deep enough. The upside is that they will hold water better than individual pots.