The following was received via email: In October 2001 I gathered several seedlings of Acer palmatum from under a neighbor's Japanese maple tree, grew them on in pots throughout 2002. They are of the usual unnamed sort - red in spring and fall and dark green in summer. In March 2003 I grafted onto these seedlings as root stock scions of selected named varieties. After inserting the scions in the root stock (cleft graft) and before binding, I treated the surface of the grafts with a chemical which I have used successfully in grafting other plant species. The chemical induces quicker callus formation and fusion of scion and root stock. None of the scions survived this treatment. I removed the dead scions and set aside the pots containing the root stock to allow the same to send up shoots. Within some weeks I noticed that the leaves of the new shoots bore scant resenblance to the original leaves of the root stock and of their untreated siblings. On all plants the initial growth is bright red and the leaf form unusual. I have no explanation for this anomaly except to suggest that the chemical treatment may have induced it. Attached hereto is a copy of the usual leaf form (above the line) and a copy of the leaf anomaly typical of all treated plants. Whether this anomaly persists into the next growing season I do not know. I would be grateful for your explanation.
Also via email: In response to your inquiry about the chemical used to induce callous formation on the subject grafts, the information is as follows: indole 3 butyric acid 1% 1-napthaleneacetic acid .5 % denatured alcohol 98.5% This was mixed with water at the rate of 1 part chemical to 20 parts water and applied by brush to wounded surfaces. Many thanks.
Interesting in that those are the two same chemicals in most rooting hormone products... the IBA and NAA that is. I have heard a wive's tale of sorts, perhaps someone can clear the air for once and for all. Regarding rooting hormones, (IBA and NAA) I was told that those two hormones were found in large amounts in both the parent tip and the new shoot tip of a cutting soon after removal, hence the scientists of the day assumed that these were responsible for root development and possibly callus formation... Any takers?
Hmmm.....I'm no plant biologist, but the formulation given is the exact ingredients in the products Dip'n'Gro, and Wood's Rooting Compound. I tried a 1:15 dilution when grafting Picea orientalis cv's to Picea abies understock a few years back, and didn't see any particular increase in callus formation. However, several of the scions developed roots from the callus underneath the budding strips! As for using this type of a product on Japanese Maples, I wonder if the alcohol in the formulation could be your problem? Late-summer grafted Japanese maples callus so quickly anyway, why mess with mother nature? Susan
The new leaves could just be the juvenile leaf form of the maple seedlings. It is common for the leaves on the second flush of growth to be different from the first growth in spring. Many times the leaves on the second flush are larger. The leaves produced on the growth the next spring usually returns to normal. This may be the explanation for the new leaf shape rather than the chemical used on the graft.