Porous, light transmissive material and method for using same

An apparatus for control of relevant pollen to or from a growing maize plant which includes a top and reproductive parts separated from each other below the top of the plant, without material damage to the plant or material inhibition, disruption, or affect on normal plant health or growth, comprising:

• a. a covering having a top, an elongated intermediate portion, and an open bottom and sized for placement over the plant top and down around a substantial amount of a plant, the substantial amount of the plant comprising at least the plant top, the separated reproductive parts and the plant therebetween, wherein the cover is tapered from a narrower top to a wider bottom for installation on a single plant;
• b. a releasable closure adapted to close and cinch the open bottom around the plant so that the covering forms an enclosure around the substantial amount of the plant;
• c. the covering comprising a flexible material which has:
• i. relatively high permeability to gas and moisture to allow effective transport of gas and water to and from the plant, the relatively high permeability comprising a Frazier value of approximately 650-1000 ft3/ft2/min. or higher;
• ii. pores of relatively small size comprising a very high frequency adapted to effectively block relevant viable pollen from passage to or from the plant by having a mean pore size smaller than normal sizes of relevant viable pollen, the pore size comprising between approximately 70/49 and 53/40 average pore size (in μm) to % effective open area;
• iii. substantial light transmissivity to allow effective passage of light to the plant, the substantial light transmissivity comprising a PAR transmission % for 400-700 nm light of at least 75%;
• iv. relatively light weight to allow draping of the material on the plant, the relatively light weight comprising approximately one oz/yd2 or less so that support other than the plant is not required;
• v. resistance to deformation, tearing, and puncture during normal handling and moderate to high wind for the growing environment, wherein the resistance to deformation, tearing, and puncture comprises a tensile MD/XD of 10.3/42 lb/in, and a tear MD/XD of 1.4/1.5 lb. or better;
• vi. relatively high percent open area, the relatively high percent open area comprising an approximate range of 40%-50% so that the covering is a barrier to relevant pollen but is not a barrier to plant growth requisites;
• vii. relatively small thickness comprising an approximate range of 2.0-15 mils;
• and
• viii. relatively high moisture vapor transfer ratio in the range of approximately 1500-2500 g/100 m2/day.