a biodegradable spectrally selective grow tube or tree shelter that improves the establishment of woody plant forms by reduction and / or elimination of certain biotic and abiotic stress factors . the grow tube may provide an enhanced micro climate that is humid , co 2 - replenished and promotes photosynthesis by selectively propagating photosynthetically active radiation . in addition to providing a physical barrier to wind and herbivores , certain embodiments of the grow tube can also provide protection from chemical sprays while permitting ventilation of the grow tube . various embodiments of the spectrally selective grow tube may comprise separate interior and exterior members for enhancement of the interior and exterior surface functions and that may be constructed from a biodegradeable polymer or paper - based material . the interior member can be dyed or pigmented to selectively transmit wavelengths of the visible spectrum known to promote photosynthesis , such as red light and / or blue light .