posted 10 years ago
From what I can tell, the tree shelters are meant serve the following functions:
-protection from wildlife
-protection from strong winds and detrimental weather
-protection from competing vegetation
-maintain a stable microclimate to give the tree seedling a good start in life
The first tree shelter that I learned about was from a gmail ad, and it was the WeedGunnel company's Tree Guard.
I forgot where I learned this interesting piece of information, but it is pretty cool nonetheless:
The guano from birds has properties that protect seeds in the early stages of growth. The sticky property of guano anchors the seeds to the ground, and the film of residue on top of the seed maintains a microclimate for the seed by trapping moisture. Then, the color of the guano, usually white, reflects all colors of visible light which aids with the creation of a miniature microclimate. Also, the guano, being what it is, will provide phosphorus- one of the three macronutrients (N,P,K) for plant growth- for the plant to grow, and since guano is a full load, it also contains the bird's urine which contains nitrogen. Furthermore, the shade of the guano would shade out and kill other grasses that might compete with the seeds in the guano.
I hope this is helpful to you.