Hi: Nice spot. Have you looked at Ginkgo varieties? I love them because they are interesting and sculptural, they have the neatest leaves and the leaf canopy never get really dense for many many years. Kids can get very interested in these relatives of prehistoric trees the dinosaurs knew.Use google images and have a look. Make sure your nursery gets you a male tree as the female tree produces fruit that really smells bad. A good nursery will know this and usually they only carry male trees. Good Luck. D

I think you should plant the Monkey Orchids. They are unique flowers and rare in the worlds. They looks like the monkeys and give a superb and amazing look. You can also read more about the Monkey Orchids.

Here is a link that might be useful: Monkey Orchids

Lol! As per wikipedia, the monkey orchid "is noted for its pungent odor, which is similar to that of feces".

Thanks douglasont. Gingko might be the tree that has been planted by the city in front of our house. The leaves are beautiful! For the backyard, I'm looking for something that will be dense. So far, I have the following options:

1. Viburnum Summer Snowflake
2. Maples: Bailey Compact Amur Maple or Emperor 1 Japanese Maple.
3. Golden spirit smoke bush, I'm reluctant after reading that the sap is toxic and skin irritant.
4. Purple Leaf Sandcherry. Again, this one is not expected to last for more than 10 years or so but it def. is beautiful.

viburnums suffer from a kind of caterpillar infestation so while they look great... there is that problem. Maples are nice- however not sure if it will provide the density you need. Japanese maples are smaller and probably will work for you.

Purple leaf sandcherries are nice. They do grow as a small tree. Service berry is a small tree and it won't provide that density you want. It's also slow growing.

Ginko's are giants just so you know.

.

One thing to keep in mind is that you don't seem to have a lot of depth in your back yard so using trees or large shrubs that grow 10 or 12 feet wide will use a lot of that space. If you google "tall narrow shrubs" you might find something that works well.

I recommend using several different types of plants to make a fuller privacy screen. Also whatever plants are locally available which are suitable for your climate are best. You might also grow some vines on the fence.

Since the Katsura tree is going to get pretty big pretty quickly, you might as well plant something that tolerates shade. Hick's Yew meets all your requirements including the 'no bees/insects' stipulation.

Thanks everyone for your suggestions!
Gingko's get big but they seem to be slow growers. The one in our front yard is doing well, but it does not grow much and is not very dense at all, yet.

I really liked the purple sand cherries, but after reading a bit about them and all the problems that could happen, I crossed it out. Now, I'm leaning towards the cotinus grace smokebush. We already have the royal purple smokebush and I love the structure and beautiful foliage on it. Besides pruning, I have not had to do much with it. I love it enough to have another one of those in my yard and thought I'd try the cotinus grace which is considered to be super pretty with its red-burgundy foliage.

My backyard is so small. The width is decent at 45 ft, which is why we planted the Katsura on one of sides and not the very back. I love trees and I just had to have one so I'm glad we got one. I wish I had more room to plant more trees. If my backyard was bigger, I would even like to add some evergreens but given how small it is and that the kids and I, only use it in the summer, I really am going for something that is low maintenance and pretty and that can provide privacy.

We do have the dutchman's pipe vine on our fence and we love it! We just picked it up from the nursery without knowing much. After we planted it, I did some more reading on it and was worried about the odor. But I have to say, our vines don't emit any such odor. They are very dense. The only thing is they all seem to want to grow on the top of the fence. I wonder if there is a way to get the vine to cover the entire fence.

We do have some sort of a dwarf evergreen next to the Katsura but that thing barely grows, maybe half inch every year :)