Hey Doc, I will try.
Take a 10-20 ft three inch diameter pvc pipe. For me 10 ft was big enough. Drill a hole 15/16 inch in diameter, and then another 8 inches down the length of the pipe this will eventually will be fitted with 2 compression collars and one wick. The wick surface (called 1/2 inch Pistachio Rope) will be eight/ inches long. About 3/4 inch further down the length the row drill another hole and then eight inches another, and so on. You repeat this until you get to the end of the pipe. Note there is a wick free gap of aobut 1 inch between the collars of two adjacent wicks. We will now take care of this.
Then repeat this same drilling again about 3/4 inch parallel to the first row of holes. Do this in a way that the second row of holes are not lined up on the holes in the first row - this is because you want the wicks in one row to overlap the empty spaces between each of the wicks in the first row - am I loosing myself , or you Doc?
You buy the kit from a feed store, it consists of wicks that are about 16 inches long and you get compression collars, rubber gromets, and caps with them. You cement the collars to the pvc pipe, let them dry. The wick is inserted into the compression collar so that the wick is inside the pvc about 4 inches on each end. you tighten the compression collars and it gives you a water tight seal so not herbacide drips out around the wicks, but only soaks them. Actually there is a slight amount of drip from the wicks, but not the collars.
You do the second row the same way. The second row wicks now alternate with the first row so that there is an overlap by the wicks and no spaces along the ten feet are without a wicking surface. Clear as mud?
You put an elbow on the end that has a screw cap. I use those large stainless steel screw band clamps and attach it to my hay fork on the front loader. With the elbow straight up in the air, you fill with herbicide (I think it is about 3 gallons per ten feet?) with some surfactant in it. It wets the wicks and then you drive off adjusting the height of the boom to top the weed and not the grass you want to save. The wick is rotated once filled so the surfaces are at 3-6 o'clock for passive filling of wicks. Six makes for greater flow, put the wicks up at 12 o'clock and it turns off so you can leave the field. The directions tell you to wick in two directions using a 33% solution of Roundup, but I had too much to do, and a friend said he used a 50% solution and only one pass - it worked for me!
I will try to take some photos of this and put it on my conservations website and then I will post the URL. A picture is worth my 2000 words, no?
Billy