The Derek, I disagree. The point of dormant pruning is to avoid any deinvigoration of the tree. A vigorous apple tree can tolerate heavy pruning most any time of the year and research shows that trees in general seal wounds just as well with summer pruning as dormant. Pruning an apple during the summer seems to reduce the risk of scorching the bark on big wood because the well established leaves pull adequate sap through the wood to cool it. Dormant pruning will leave the tree more vulnerable to this kind of injury in early spring as tree begins growth and newly exposed bark heats up before leaves are developed enough to bring about adequate evaporation and transpiration. In my opinion and considerable experience you can actually safely prune more wood in the mid- summer than when the tree is dormant, although I aggressively prune old apple trees pretty much any time and spend about 700 hours a year doing so. The only time when I'd hesitate to summer prune a tree is if it is senescent or diseased and just not vigorous enough for any reduction in energy harvest.

commercial growers often prune in the winter because that is when the labor force is looking for something to do....professional growers and pruners have more time during this season and get busy picking peaches or apricots or some such in July or August. So, professionals often prefer winter pruning and this is what has helped to popularize this. Sometimes, too, growers want to stimulate new growth on their fruit trees, and there is more new one-year growth when you prune in the winter. So, for SOME pruning, winter pruning is preferred. I personally like to prune in the winter because you can see the structure of the tree much more easily and you can get into the tree more easily. Having said all that, I am pleased to see that a "re-education" process is going on with the homeowner now where many of us are dis-abusing people of the myth that they have to prune in the winter. Not only does one not have to prune in the winter but in terms of de-invigorating the tree and reducing sucker growth the preferred time to prune is in the summer months.....most homeowners should focus most of their pruning efforts in the summer, especially if they have an over-vigorous tree that is not on a dwarfing rootstock and which they wish to hold down to an acceptable height. Homeowner discretion is okay here....and to some extent, you can generally prune in the winter, spring or summer as you feel like it though.....so don't sweat it one way or another, especially if you are in a moderate zone. I have a question of my own here, though.....We know that fruit trees, especially apples and pears, can withstand cold temperatures after having been pruned, even sub-zero temperatures, but my question is does it hurt the tree any to prune in below freezing (below 32 degree) temperatures if the tree has been in below freezing weather for a few days where the temp never got above 32 degrees fahrenheit? In other words, I know it is okay to prune apple and pear trees now in most places and not worry if it gets cold later, but is it advisable to prune in a place like, say northern Idaho, in the middle of a freezing period?

Alan: I think you may be onto something there, leave a few fruit hanging in the fall and see what happens. I've always enjoyed eating dried apples both dry and re-constituted. Perhaps drying on the tree would work well on some varieties in some years at least. Merry Christmas to you and yours, Michael

If, as you say, they are "beyond saving", then no, they're useless as root-stock. They're not magically going to recover just because you graft younger material onto them. As for scions, if these are still alive, sappy and growing healthily, there's no reason they won't grow into healthy branches/leaders when you graft them onto new healthy root-stock. Having said that, if any of the old trees still show signs of fairly vigorous growth, I'd be tempted to try a couple of grafts onto those. Grafting is a skill gained by experiment, trial and error and the experience you gain from both failures and successes.