MR. A. M. WHITFORD: I have trees of that very spreading type of Chinese chestnut, that are lying on the ground and I should have removed those limbs five or eight years ago. You should remove them in not more than five years after planting.
DR. McKAY: I want to make a comment. Some grafted trees are not bearing. This to us shows the importance of varieties. This difference between 7916 and the two others is so striking it means in the future we have to pay more attention to the varieties. There is no question that some varieties will bear sooner than others. We have to talk about grafted trees because that is the only thing that can be developed. Every grafted tree is potentially like every other of the same variety.
MEMBER: What factors suppress them? In pinching back, do you mean that the actual growth rate is changed, or that debudding will suppress the entire tree?
DR. McKAY: We mean the amount of the top itself. Usually it is the spread and the height together. When you prune, you tend to hold back the total amount of the fruiting area of the tree. If you allow it to develop untouched you have a greater fruiting area.
MEMBER: The chestnut tree often will sprout from the trunk. What are the processes to check that?
DR. CRANE: It is very largely root pressure. When you have a tree that is uninjured, all of your water and soluble minerals are going up to the top. When you have the tree trunk killed or cut off you still have water in your root system. In some trees you have a lot of adventitious buds that are still there and never forced out. Nitrogen will force those dormant buds into growth. At each walnut node or leaf we have as many as seven buds, all of which are capable of producing growth. Normally it is only the major bud that grows, but propagators sometimes get a patch bud back to life even though the primary bud dries up. Keep on forcing it and you are bound to get a sprout out of that bud. That is just the way it is with a lot of dormant buds. There are so many that when we cut off the top these dormant buds are forced into growth. Some trees don't have them. Tung does not form dormant buds, but will form those adventitious buds. They will form numerous buds even in a very small area of callus. It is just a safeguard that some plants have developed to keep the individuals alive.
MR. McDANIEL: I think what Mr. Craig had in mind was the tendency there is in Chinese chestnut to form multiple trunks.
DR. CRANE: That is due to these dormant buds and the ability to produce callus. Chestnut is one of the species that produces abundant callus very readily. That is one of the reasons this Chinese chestnut is so blight resistant. When it has an injury it will form callus at the point of the injury.
MEMBER: Would you tell me how you would start a blind bud growing. It will not break. It doesn't form. When I come to a wood which is blind I cut it off.
MR. CHASE: We have had such buds and find if that bud is blind you can force all you want to but you won't get any new buds to grow from that bud patch.