Like Diggingthedirt, the only thing I cut back in the fall is the peonies. I leave everything else in place - both perennials and annuals. There are several reasons for this. I kind of like the "messy" look, and enjoy the foliage as winter interest, especially when there is a snowfall. The foliage provides some wind and privacy screen along the front of the house during the winter when things are bare and the winds coming from the farmland across the street are just brutal. Also, the standing plants catch lots of leaves that blow around in the fall/winter and this provides mulch for the gardens over the winter. In the Spring I actually just rake or pick out whatever stray foliage remains and continue to use the leaves as mulch. Last but not least, the birds enjoy picking through the leftover seedheads and the foliage provides places for beneficial insects to over-winter. Anyway, I definitely wait until early-mid Spring to cut back the Buddleia, just about the time I see new shoot sprouting. And yes, once cleome gets going, it re-seeds prolifically - but I love cleome, and use it and other annuals to fill in between the perennials and shrubs.

I have a 'pink fleshed' apple that is a natural dwarf and is staying quite small without much pruning. Also, I recently read an article on summer pruning for fruit trees. The author's POV was that it takes two prunings yearly to keep dwarf fruit trees at an appropriate size. Dormant pruning in the late winter is for shaping the growth but does not limit size, a second pruning in the late summer should keep the tree from getting too big. But fruit trees have their own problems - mainly fruit dropping and rotting if it is not all picked. I faced a similar situation and ended up choosing a large shrub that could be trained into a tree-like form.

I like pagoda dogwood, Cornus alternifolia. It grows wild around here, so should be hardy for you. While not necessarily narrow, it's about the right height, multistemmed, and can be pruned to reduce the number of stems so it isn't as bushy. It has elderberry-like flowers in the spring (not largebract-flowers like C. kousa or C. florida), nice berries with bright red stems that ripen to dark purple in August, and soft yellows, reds and purples in the fall foliage. Winter stem silouettes are nice as well. No one aspect is totally stunning, but it has true year-round interest and the birds love it.

There is significant overlap on the list of plants to avoid digging in the fall and the list of plants recommended to be sweated. It's quite possible the plants recommended to be sweated could benefit from fall planting, but NOT if you dig them in the fall...spring dug b&B, or container. I can't say as I've heard, or pondered, the question phrased in this way. I can say, I plant more plants in a week than most people do in a lifetime, and my list of plants that prefer fall planting would be as outlined above. Last winter, I sat in on a presentation about producing maple sugar. My background is horticulture, and before that dairy, so the maple world is new to me. What surprised me was that according to the narrative of the presentation is that just about everything I thought I know about tree biology and seasonal behavior, based on a horticultural education and years of experience in nursery production, was apparently unknown to the post graduate degreed staff of one of the only maple research centers. Which begets a series of questions about how do we know what we think we know when it comes to woody plants, physiology, seasonal behavior, and similar tangents. Before this morphs, let this be stated...the presentation was from the head of the Proctor Research Center, attached to the U of VT, and was specifically re: the new production system using high density plantings. This was the end result of a experiment supposedly designed to test how sap flowed in trees, specifically sugar maple, in the spring. So how much of the narrative was in telling a story, how much was just people pondering what could be done, and how much was truly unknown, I have no idea. But the idea of sitting in a presentation where people with advanced in plant physiology supposedly didn't know one of the basic things about tree physiology really makes we wonder how we know what we think we know. The truth is, there is a lot we think we know. No one is going to repeat every experiment on every plant...there may be that many people looking for research projects, but there's not going to be the funding for it. So what we know about this species, based on specific research, is going to be extrapolated. Which ultimately gets us to the current question, or more specifically, the application of the question in dealing with sassafras and persimmon. Ultimately, I'm not sure the nuts and bolts research has been done. If the answer to the question does exist, it's possibly buried in obscure journals that only exist in the bowels of research institutions. More likely, bits and pieces of the answer are locked away in the brains of individuals such as the head propagator for Johnson's...or Sherman's...or Bailey (yeah, I know the ownership of the two)...or Forrest Keeling...or one of several dozen other nurseries or research centers (specifically avoiding Monrovia...never can get a decent answer out of them unless it's how many they want to sell me). So at some point, we get to questions that people ask, and it's possible that question has never been asked to the right person before. the right person would be the one who is going to draft a grant proposal that gets approved to do the research. Could this be such a question? Perhaps? That's a topic in and of itself, and the kind of esoteric discussion best held in the rarified air of Colorado...and soon, maybe a state near you.