Grow

Let nature take its course and watch trees develop into beautiful shapes. Mimic any tree’s character with intuitive parameters taken straight from the woods.

Grow feature illustration

Terminology

To learn how to grow your own 3D tree, first quickly get up to speed with terminology in the tree world. A branch consists of a series of nodes. The number of nodes and the length of the branch depend on its health, its species, the age of the tree and growth hormones.

Nodes grow buds, which will develop into a side branch the following year.

Twigs are fresh new branches that were grown this year. They are very different to the rest of the tree – they have leaves, flowers and fruit – they look and behave just like smaller plants. Also like small plants, many twigs don’t survive the winter, but the ones that do survive turn into woody branches. The biggest woody branch that started the whole tree is called the trunk.

Pick Preset

Nature has had millions of years to evolve its presets; The Grove humbly tries to capture these iconic growth forms.

The Grove currently comes with 40 presets that cover a wide range of tree characters. Studying these will soon teach you each parameter’s impact on a tree’s shape. You can save your own presets by clicking the little icon at the upper right corner of the interface.

Presets are saved as plain text files describing all relevant parameters.
On Windows, presets are saved to: Users/{Username}/AppData/Roaming/Blender Foundation/Blender/{Version}/scripts/addons/TheGrove{Version}/Seeds/
On OSX, this is: ~/Library/Application Support/Blender/{Version}/scripts/addons/TheGrove{Version}/Seeds/

Add Side Branches

Every node has a chance of growing a new side branch. Some buds get damaged by frost or insects, others remain dormant. The parameter Branch Chance controls the chance of a bud to grow a side branch.

Most buds are created on fresh branches, a chance that is gone once the branches grow thick and woody. But there is still a chance for an old node to grow a spontaneous bud. Some species grow lots of spontaneous buds, especially after heavy pruning. Trees damaged by storm or insects will also fight back and grow extra buds. The Regenerative parameter controls the chance of forming these regenerative branches.

The Add Side Branches menu allows you to choose how many side branches a node can develop. Most trees grow a single bud at each node, each successive bud alternating sides on the branch. This is what botanists call alternate branching. A small number of trees grow two buds at each node – one at each side – called opposite branching. Trees like Maple, Horse Chestnut and Ash show opposite branching. Depending on the growth power of the branch, a pine tree can create an entire whorl of branches.

When a bud does grow a new twig, it’s at an angle to its parent branch, the Branch Angle. This determines the initial direction in which the side branch will grow. This initial direction can also be pulled To Gravity or away from gravity, along with some Random variation. An effect also seen on many trees is that buds are pulled toward the horizontal plane, simulate this with Horizontal Buds.

Growing a new twig

After the fate of a bud turns out favorable, it pops open to grow a new twig. This twig will grow a length of New Nodes times Internode Length. It will grow at an angle to the parent branch, the Branch Angle.

Nature exposes trees to forces like wind, cold and even insects. A branch experiencing these forces rarely grows in a smooth line. So add some realism by randomizing each new node’s direction with the Random Heading and Random Pitch parameters. Heading is the horizontal direction, pitch is the inclination toward vertical.

Now what makes a tree grow up and its roots grow down? Trees regulate growth with hormone molecules, communicating what to do to different organs. The distribution of hormones determines which parts grow and which way it grows. Some hormones are free to move by gravity, concentrating at the bottom of branches. By growing more cells on the bottom of a twig, it bends up to the sky.

Botanists call this effect gravitropism. Tropism is a fancy word for bending or turning, Gravi is short for gravity. I just call it Turn To Gravity. Most trees show a negative gravitropism, with twigs turning up to the sky instead. The effect of gravitropism is partly countered by bending under weight.

Grow groups of trees

The shape a tree evolves to depends a lot on its surroundings. A tree growing in open field has no competition for light and can grow a wide crown shape. In a grove of trees, the inner trees tend to grow higher and much more slender while competing for light and space.

True to its name, the Grove grows groups of trees just as well as a single tree. Watch trees compete for light and form a unified, well balanced crown shape. Grouped trees are often much more appealing and add natural realism.

Need to create a hero tree with total control? Sculpt your own trunk and main branches. Then distribute empties where you want to finish off the tree with grown branches.

Nature or nurture

The Grove has a strong eye on realism. Let nature take its course and watch trees develop without labor intensive user input.

No painting of new branches, no precise control over numbers of sub branches. Although these features give an artist control, they make creating a balanced tree a hard job. Following the rules of nature makes for a predictable and surprisingly easy experience. Despite the complex algorithms under the hood, the Grove is a joy to work with.

With the Grove, like in nature, you can shape a tree with an environment object. Learn more about environments in Interact.

Know your tree

A recent study by Yale University estimates there are a total of 3 trillion trees – 420 trees to every person – on earth. They surround us everywhere. We think we know our trees, yet the mental image we have of them is often quite different from reality. If you want to recreate a tree species, observe it with care. Find pictures of the tree at different ages. Winter time is when a tree’s branching structure is best visible. Try to get your hands on a twig and model it to scale.

Get to know the ins and outs of tree growth with the Grove 3D tree growing software. Read the blog post on How Trees Grow to get into the terminology.

Next up, learn more about: Bend.