The Shape Of Trees – A Visual Guide To Tree Forms/Crowns

This post is just a short guide to the different forms of trees, often referred to as the crown of the tree. When you are selecting trees for landscaping or attempting to identify trees in the open, an understanding of the possible tree crowns can be of great use. By the end of this, you should be able to identify a tree crown from it’s silhouette at night, or in the winter when the leaves have fallen.

Now, tree shapes/crowns are useful when a tree is grown in the open, and differences are more pronounced when trees are young (<30 years old). As a tree ages, it’s shape will be modified by it’s diameter, as all trees tend to get a bit fatter as they age. Also, trees are opportunists in that they will steal sunlight from where ever they can get it. And so if a tree is grown in or on the edge of a forest, or has irregular lighting it’s form will likely not resemble any reference book! But a lone tree on the horizon? Yes, that one should match.

Columnar

Columnar Trees are shaped like, well, columns. These trees will require minimal pruning and are quite narrow. Examples of these would be Red or Sugar Maples, Pin Oak, Tulip Poplar, and various evergreens like Pinus sylvestris.

Fastigiate

Fastigiate trees is basically as special form or sub-form of columnar, but is a bit more narrow with a height to width ratio of 10:1. And as such, these style trees are the most popular for creating privacy screens as they can block a neighbor’s view yet don’t take up much space.

Some nice examples of Fastigiate trees would be American Arborvitae (White Cedar), Bald Cyprus, and Italian Cypress.

Columnar vs Fastigiate

Although both columnar and fastigiate tree forms are tall and skinny, there is an actual dendrological defined difference! Columnar trees have a broader base, and their height to width ratio is 5:1 where as fastigiate will have a 10:1 ratio. One important thing to note – as trees age they will often get much wider. So even the tall skinny fastigiate trees can end up broadly columnar if one doesn’t maintain them!

Conical / Pyramidal

Conical trees are shaped like cones, and they can be used for privacy screens or as specimens with beautiful forms. The most common example would be fir trees such as Hemlock, Douglas or Fraser Fir (popular Christmas trees, naturally!), Spruce.

Pictured: (White Spruce)

Broad / Spreading

Trees with a broad or spreading crown will have their branches grow horizontally, even at the top! These trees are often deciduous, and will grow progressively wider over time.

The most famous examples of these would be Oak trees, particularly Red Oak, White Oak, and Black Oak. .