Hi gardenfan. Perhaps you are thinking of "standards". If you go to the Topiary forum and search on standards, you will find some information. Good luck. Lynne

Janice,
This is also known as "limbing up", when it is done to existing multi-stemmed shrubs such as Oleanders, when it is desired to make them appear as multi-stemmed trees rather than shrubs with branches to the ground. What you decide to use in this area will depend greatly on whether it is full sun or shaded. Hibiscus really only works with enough sun, Podocarpus will work with either, but do eventually want to get to be big trees, so will require regular shearing to control size, and the trunks may eventually look out of scale for the size of canopy head you wish to maintain. I would consider using shrubs that will remain at more or less the size you prefer. Other flowering shrubs that come to mind, would include Feijoa sellowiana/Pineapple Guava, Tibouchina urvilleana/Princess Flower, Psidium cattleanum/Strawberry Guava, or Bambusa multiplex 'Alphonse Karr'. Sasanqua or Japonica Camellias could also serve your purpose.

None of these will stay narrow indefinitely, and will all need occasional pruning to control width on both sides of the fence, although the bamboo is more vertical, so it would require the least.

Janice,
Podocarpus is the perfect shrub for your situation. I use it a great deal for my topiaries. It can be pruned any time of the year and is nearly indestructible. Select plants with a single trunk. Multiple trunked ones will not give you the 'flat' look you need. Pay attention to the branching as you purchase and plant noting which branches will grow sideways. There is on the market a product called 'single-wrap Velcro'. Although there is a cheap version of it available at box stores, I use small pieces of a stronger type to secure and weave podocarpus branches just where I want them. It works well. If interested send me an e-mail and I will tell you where to purchase it on-line. Not readily available. Yes, if you wish, it is possible to remove the bottom branches of podocarpus so that your fence would be exposed.

On the other hand you are more likely to find 'pleaching' the method you are looking for.

Hmmmm...."pleaching" is a training method of weaving, plaiting or braiding the supple young branches of trees (usually) or shrubs together to create a living fence, arbor or allee. Typically, pruning is not a huge factor in this process.

The weaving occurs at the top of the tree/shrub and the lower part is 'limbed up', the whole process is called pleaching. Lime is a good and much used subject, google 'pleached lime'gardenfan to see if this is what you had in mind.

There is also what is called a "stilt hedge," which is a hedge in which shrubs (or trees) are limbed up from the ground to a particular point, and then trained by shearing and pruning into a dense hedge from that point up. They do like clouds of green atop stilts.

The oleander hedge you describe sounds like that.

Note:
Lime = Linden (genus Tilia) for us "non-Lime-ys" ... sorry for the bad pun, Ink.

Thank you all for the advice. Incognito, "pleaching" was indeed the term I had heard. (Don't you all just hate that when you can't remember the name of something. It is really frustrating!) Gardengal, you are right. It is not a pruning method. Cady, you are right, too. What I saw on the oleander shrubs was probably a stilt hedge. Whew! I'm glad you are all so knowledgable.
Janice