Hello cheuh, You determine what is important. A plant is more or less the same from one landscape to the other, but the role they play and the inherent characteristics which are emphasized change. A camellia could be a stunning accent in one garden and a ho-hum hedge in another. In one case, it is being employed for its flowers, in the other, its massing. "Importance" is a tricky word, as it implies an intrinsic value. Allow me to recall that, and substitute it with "emphasis". What is intended to grab the attention? What do you want noticed? It is something that you can manipulate with a huge variety of techniques and to which there is no known universal equation. I gave the example of using size to give order to the design according to spatial impact. Yes, the largest trees, having the largest bulk, create a larger effect on the space. That doesn't mean the largest trees should or do garner the most emphasis; the trees which structure the space could simply be a background to which other plants or elements play. Or not. Laag gives one example of manipulating emphasis. Perhaps one way of thinking of significance/importance/emphasis is in terms of portions. A greater number of portions means each one is individually smaller. Having fewer portions also allows for having larger portions, too. Sometimes this isn't true, though. Placement, alignment, contrast (in forms, colours, texture, movement, size), repetition - all of the "how a plant is used" - have an impact too. It would be impossible to cover all the ways in which something is manipulated to become more important, more emphasized, or more significant. One of the best ways to figure out which manner you wish to manipulate them is by example; find what appeals to you, and analyze it until the cows come how. Exposure to different designs will help with this. (It is also handy if they have both plans and photos of the design, instead of just one or the other, since both can be deceiving to their alternate form). - Audric

Thank you so much Chris, that's exactly what it is! Now I know there is no way I can let it grow where it is. Thanks again. Elia

Before you do anything contact your county office of the Michigan State University USDA Cooperative Extension Service and inquire about having a good, reliable soil test done (about $13.00) so you know what your soils pH and nutrient load is and what things that may need to be done to correct any problems, or get that soil into a condition that will grow a good healthy stand of grass. The dig in with these simple soil tests, 1) Structure. From that soil sample put enough of the rest to make a 4 inch level in a clear 1 quart jar, with a tight fitting lid. Fill that jar with water and replace the lid, tightly. Shake the jar vigorously and then let it stand for 24 hours. Your soil will settle out according to soil particle size and weight. A good loam will have about 1-3/4 inch (about 45%) of sand on the bottom. about 1 inch (about 25%) of silt next, about 1 inch (25%) of clay above that, and about 1/4 inch (about 5%) of organic matter on the top. 2) Drainage. Dig a hole 1 foot square and 1 foot deep and fill that with water. After that water drains away refill the hole with more water and time how long it takes that to drain away. Anything less than 2 hours and your soil drains too quickly and needs more organic matter to slow that drainage down. Anything over 6 hours and the soil drains too slowly and needs lots of organic matter to speed it up. 3) Tilth. Take a handful of your slightly damp soil and squeeze it tightly. When the pressure is released the soil should hold together in that clump, but when poked with a finger that clump should fall apart. 4) Smell. What does your soil smell like? A pleasant, rich earthy odor? Putrid, offensive, repugnant odor? The more organic matter in your soil the more active the soil bacteria will be and the nicer you soil will smell. 5) Life. How many earthworms per shovel full were there? 5 or more indicates a pretty healthy soil. Fewer than 5, according to the Natural Resources Conservation Service, indicates a soil that is not healthy. to help you know more about your soil and what needs be done to make that soil into a good, healthy place for grass to grow strong and healthy and better able to keep things sucj as "weeds" from growing there. Here is a link that might be useful: MSU CES

Before I'd make that ^ pronouncement, I'd question OP about what is meant by a 25 ft. limit in size. I'm about as sure as a guy at a computer at a remote location can be that what he/she means is that the yard section or whatever little plot this is is 25 ft. wide. That simply does not say anything about what tree can or can't "fit" that spot. Remember dear readers....large-growing "shade tree"-type trees, when mature, exist as a trunk somewhere out in the yard. The trunk may grow large, but no tree I'm aware of in the N. temperate zone is going to have a trunk 25 ft. wide. What is almost surely the case is that any large-growing "shade tree"-type tree could in fact easily inhabit that space...and at maturity, would consist of a trunk with all the tree up high overhead. Such trees form living ceilings over our "outdoor rooms" which is what landscaping seeks to provide. Take that same 25 ft. wide area, plant one of the ornamental, low-crowning species, and now you really have taken up all that space. Nobody can throw a ball around, nobody can even just walk there, because there's a big, wide-spreading ornamental tree crown in the way. That's the reality of this big tree/small tree conundrum-that many folks get it exactly backwards-the large-growing type-at maturity-taking up less space than the little redbud, fl. crab, or what have you. People that give out lots of landscape advice should learn to recognize this elemental fact.