ROTFLMBO ...

if all you want under them is grass... so be it ..

i am of the opinion.. you cut them.. when you walk by them with the saw ... and thats the end of it ... even if they weep wildly for a month in spring ...

now.. if you had 1000 acres of your retirement wrapped up in production trees .. and a plague could wipe them out.. i might want to know about timing ...

otherwise.. my eyes rule ... and if there is any inclination.. to poke me in the eye.. the branch has to go ...

and just to be sure.. we dont just 'cut them back' .. we prune them properly.. you know about all that???

thx for the chuckle...

ken

I typically prune my maples just after leaf fall, so I've already done it for the year. Reason being, they tend to sap heavily in late winter. That being said, you're probably okay to do it any time other than deep winter or maybe a very hot summer. It's also just easier to see the structure when there are no leaves on the tree.

I'd recommend the book linked below. It's a pretty handy resource.

Here is a link that might be useful: AHS Pruning and Training

Yes Jeff, late winter/early spring is the best overall, and some exudation of sap from a pruning cut wound simply indicates that the tree is healthy, having a positive pressure as compared to the surrounding air. Also, if Dutch elm disease is prevalent in your area, that alone is reason to not prune elms during the growing season, when the insect vectors that spread that disease are active. Same holds true of oaks in oak wilt areas.

+oM

Tom, why wouldn't the reverse hold true? That is, is it best to prune a susceptible tree while it is actively growing? That way, the cut would be healed as soon as possible. For stone fruit (Prunus species), it is recommended to prune in the very late winter or even after bud break. Those trees are notorious for fungal infections.

Also, can White Oaks be pruned anytime because they aren't affected by the predominant blight like Red Oaks are?

Pruning a Walnut / Hickory this time of year causes a flood of sap. This can't be good for a tree. Bleeds for days.

Dz, here's what I know, or think I know: With both elms and oaks, the insect vectors are active during the growing season, and since these insects are attracted to fresh wounds, including pruning cuts, it's best to not be making those wounds when the insects are out and about. As to white oak and oak wilt susceptibility, it's all relative. True, members of the white oak fraternity are less susceptible to the full ravages of oak wilt, but they're not immune. I never heard about pruning Prunus after bud break. That is also the time of maximum disease pressure, so I don't understand why that recommendation would be out there. And especially for so disease-prone a genus.

+oM

Hey Tom. Everybody around here prunes the peaches and cherries last, after apples, pears, etc. The reason for pruning Prunus last (sometimes when blooms are open), is that the rule is to prune only when the tree is growing so it can cover the wound as fast as possible. An open wound invites trouble because as you say, these trees are prone to a multitude of pests. The last few years have seen more small orchards (25-50 acres) prune after petal opening and take the prunings to market. Open Prunus blooms on the long whip growth sell.

The old rule was to prune after any hard frost could occur because the frost can damage the cut bark. (Prunus are thin barked trees.) This leads to May pruning, and the orchards are too busy in May to do pruning unless you have a good crew. With the explosion of farm markets, you prune the Apricots first (March) because they wake up first. By the time your late peaches are pruned, spring is full blown. That's here in the Mid-Atlantic. Things farther north could be different, but winter pruning is not recommended for Prunus here.

I found this link from Penn State. Pruning is down about 1/2way.
http://pubs.cas.psu.edu/freepubs/pdfs/ua429.pdf