Fruit & veg
Strange root growths from apple tree stem
, the green wire was a temporary fix that should have been removed but was forgotten! It's on my list for the weekend
PEAK DISTRICT Derbyshire
Here is a dense discourse about some scientists who tried to tell the difference, if any, between burr knots and crown gall by doing a series of experiments on different apple trees.
I no longer have the brain power to understand their findings and I don’t know what conclusions they came to in the end, but it would seem as if they were as confused by it as the rest of us.
Apophthegm - a big word for a small thought.
I don't suppose this is much help, but years ago when I was a biology undergraduate, we were taught that galls are the plant equivalent of cancer. They are areas of abnormal growth often caused by viral infection. Some of these infections remain local, eg oak apples, and don't harm the plant, and some are systemic and will cause the plant to sicken and sometimes die. The viruses can be airborne and enter the plant through random injuries, or may be introduced by insect bites.