We recommend installing a manifold and ranks of underground tubing in the manner of a drip system, but under ground for alternating CO2 and water distribution.  A 12 to 18 inch depth seems ideal as seeds are installed at a few inches.  The actual depth will vary from one plant species to another, but the CO2  must be released at a depth sufficient to insure capture by  moisture present in the soil.   The technology of the new systems is sufficiently like the old above-ground systems that no great difficulties are anticipated installing the systems.

We have designed a stomata-like valve for CO2 and water dispensing with the idea it will make very long lines for crop rows practicle.  The ideal crop row is long because there is time loss with equipment having to turn around at the end, but very long water and gas delivery lines give much more to the end near the source than at the end of the line.  Our valve is made with a permeable plastic that swells shut after a certain amount of water or gas passes through.  If we can design these valves sufficiently well they will all shut when the correct amount of gas or fluid has passed and we can use the rise in pressure to signal a shutoff.

Plants give good indication of their condition with color and curl of leaves.  The broad-leafed plants are easy to read.  If they need water or CO2  the leaves will curl at the edges obviously.  Corn and wheat are not such good indicators.  The leaves curl when they are distressed, but it is harder to see as they are normally curled.  If they turn brown the plant is pretty well gone so we will have develop monitering systems to determine the frequency and quantities of water and gas needed for optimum growth.

Gas The Pests

Drip systems save considerable water and control weeds by dehydrating them while only inches from watered plants.  An underground design would control weeds, rodents and insect pests if row crops were planted directly over the watering and CO2 fertilizing tubes.  The gas will chase or suffocate rodents and insects in the root perimeter.  Water and gas are dispensed in a way and in quantities that limit both to the area normally covered by the roots. Cutting water beyond the plant root perimeter dries weeds to extinction for total pest and weed control as a benefit.