Law #2
A treeshelter cannot "amplify" a certain wavelength of light (even though some treeshelter makers claim their product amplifies certain wavelengths of light). For example, a red treeshelter cannot have more red light in the interior than exists in full sunlight. However, a treeshelter can have a higher ratio of red light relative to other parts of the light spectrum.

Law #3
Plants do not use Green light. That is why plants are green: they reflect (and therefore "reject") green light while absorbing other light. In fact, a growing body of research strongly suggests that an environment that is rich is green light (as a ratio relative to other frequencies) actually inhibits plant growth. If a green treeshelter is rich in green light (Law #1).

And if Green light inhibits growth...

Then by definition a green treeshelter cannot be a "grow" tube.

Law #4
Plants use blue and red light for photosynthesis. Together, blue light and red light are known as Photosynthetically Active Radiation - often shortened to and more easily remembered (at least for golfers!) as PAR.

Law #5
The primarily role of blue light is governing apical dominance... making blue a poor choice for treeshelter color. Plants grow toward blue light. Look at the sky. It is light blue at the horizon. The deepest, darkest blue is directly overhead. That is what the apical bud - the leader - is growing toward. As it does it produces hormones that suppress the growth of the branches below. This is called apical dominance. In a blue treeshelter the plant is surrounded by blue light - by the middle of the sky. This interferes with the plant's natural apical dominance.

Law #6
Red light is the most important fuel for driving photosynthesis and biomass growth... making red pigments (and therefore a "Peach" color when blended at the right percentage) a GREAT choice for treeshelter color.

Remember, when it comes to plant growth: Red means "Go"

Green means "Stop"

Blue controls the direction (the photosynthetic equivalent of a backseat driver)

Therefore, the ideal treeshelter: Absorbs green light

Absorbs blue light, while allowing blue light in at the top

Creates an environment rich in Red light (as a ratio to other wavelengths)

Law #7
White or Ivory treeshelters reflect and transmit all light nearly equally, doing nothing to create favorable conditions for growth.

White or Ivory colored treeshelters: Transmit the green light that inhibits growth

Allow a higher percentage of non-PAR light into the treeshelter, increasing the temperature without contributing to growth.

Law #8
Light diffusion increases light absorption by the plant's photoreceptors… and therefore increases photosynthesis. Plants have photoreceptors that are oriented with many different "angles of acceptance" in order to absorb red light as the sun move across the sky. Twin-walled (corrugated) treeshelters diffuse and scatter transmitted light so that it strikes the leaves from more directions, increasing the number of photoreceptors that are actively absorbing red light at any given moment. Single-walled treeshelters transmit more focused light, reducing the number of photoreceptors that are actively absorbing red light at any given moment.

Law #9
Far Red light = Shade avoidance = Spindly stems and weak roots. Humans can't see Far Red light, but plants can. More specifically a plant photoreceptor called Phytochrome can see Far Red light - and measure the ratio of Far Red light to red light. Plants absorb red light for photosynthesis (Law #6). Far Red light passes through leaves like panes of glass. Therefore, in the shade the ratio of Far Red light to Red light is very high.

The phytochrome senses this high FR/R ratio, and triggers a growth pattern called "shade avoidance." Shade avoidance growth is characterized by: A thin, spindly stem

A weak root system

A plant in shade devotes all of its growth energy into reaching for the sun (avoiding shade). This is a good strategy for a plant unfortunate enough to germinate in the understory of other trees. However, it is a very bad strategy for a treeshelter.

A well-designed treeshelter creates an environment rich in red light while reducing Far Red light.

Law #10
None of the above matters if the diameter of the treeshelter is too small.
3.5 inches is the "magic number" in treeshelter diameter. Even a treeshelter that is rich in red light will not increase total biomass growth if it is smaller than 3.5 inches in diameter. Less than 3.5 inches in diameter = Rapid height growth, but with a spindly stem, less total biomass (volume), and a poor root to shoot ratio.

Greater than 3.5 inches in diameter = Rapid height growth along with thicker stem, more total biomass, and a balanced root to shoot ratio.

So, the Ideal Treeshelter is:
3.5 inches in diameter or more for balanced growth.

Twin-walled for to diffuse (scatter) light to optimize absorbance by photoreceptors of various “acceptance angles”.

Rich in Red light while absorbing Far Red light.