"I'm sure everyone says that."

You can say that again, and again, and again, and again......

You might want to search the forum where this subject has been discussed to death many many times. You could use a search term like Green Giant. If you have any specific questions about what you find, come back and I'm sure we can get you an answer.

$50 per tree is real expensive if you are talking about Green Giants. Buying fast growing trees that are already 5 feet tall is probably not a good idea. You'll be paying more for less performance. Smaller trees would probably surpass the size of larger trees within just a few years. Smaller trees experience less transplant shock, are less likely to have girdling roots and poor root structure, are easier to plant, are easier to care for, save you time (because they grow faster), and cost less! 2' to 3' Green Giants are a good size if you go with Green Giants.

Getting growth rates of 3' or more a year is possible if the trees are very happy (given the right conditions).

See some of the many many other posts on this subject for other recommendations (other species and mixes of different types of trees) and planting schemes.

I know nothing of Missouri, but I can vouch for White Pine. Becomes a nice full tree with attractive bluish green needles and has beautiful pine cones. Hopefully it does well in Missouri.

For more interest and better resistance against a single disease/bug, consider planting a couple different things (mixed border is what it is called sometimes). The concept works better if you don't have to do it in a straight line (so it may not apply for you).

In addition to the link below, here is another to look at:
http://mdc.mo.gov/forest/urban/urbantre/1con.html

Here is a link that might be useful: Here's a nice link from Missouri about evergreens

You may want to post in conifers for additional advice. With the price you indicated Green Giant is likely your best bet. If space isn't an issue I would mix in Norway and Blue spruce. How wide and long of an area are you talking about?

David

Ditto the comments on smaller trees.
The evergreens I'm familiar with that might do ok up there:
Leyland Cypress grows fast. It might approach 36" per year.
Thuja Green Giant per most reports is not making 3' per year. It probably will make 2-2.5' where you are and its probably a better tree than Leyland.
Eastern Red Cedar will make about 2' per yr. in good conditions.
3' apart is too close for these trees, more like a distance for Holly or some other evergreen shrub than a tree. Pines generally grow the fastest but will not make as good a screen. Good luck.

I'm in Kansas City too and I can give you a couple photos of a Leyland Cypress that has grown more than 3 feet a year, if not around 5 feet a year.
Yeah, I'd say 1 and a half feet for each tree to grow won't be near enuff. You must want an instant screen. I think some sort of fence would be better if it has to be instant.
I know that Leylands can take some serious pruning into a hedge/screen shape but I'd give it at least a year and at least 8 feet apart.
I've seen photos of Leylands pruned into the shapes of poles, and hedges. In order to keep a great hedge with them you'd have to stay on top of the regular pruning or they'd soon be out of reach of you and your ladder.
I initially bought this Leyland at Lowes for $13, in a 2 gallon pot.
Although, I do think Leylands are on the edge of hardiness in KCMO. Unless you have a sorta protected spot or maybe a south facing spot. I was always impressed with this one because it seemed to really thrive. I planted it at my mom's and as luck would have it she had it cut down because of some minor tip browning and it had gotten lopsided.
Its the green one in the pot in the small plant photo.

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