Thanks for all the suggestions and input guys. :thumbsup:
I talked to one of the companies sales guys today and ordered me a 300 gallon water wagon.
I was on the edge of getting the 200 gallon because of some ideas and concerns brought up in this thread, but the main selling point was there is only a $300 difference in price between the two and I can always put in less water.
$3300 should be a good investment in the hear-n-now and the future.
with others low to the ground trailer possibly double axle trailer, with a brake installed on it. with a hand lever mounted on stearing wheel of tractor to control brake. i might suggest a water tank that is made to fit in back of a pickup truck. they are generally made to be not as high vs other water tanks.
TIP: do a search for "septic tanks" on the internet then once on a given website then look for water tanks. searching for "water tanks" is useless search and returns ugly mess to sort through. ((been there done that many times)) 80% of websites over the years that sell septic tanks also sell tons of different styles of other water tanks. some with baffles.
a PTO driven water pump possibly. if or on-demand eletrical pump. to drive some custom made booms. one boom for each side of tractor.
i can not picture how each boom would work or be placed right this minute. but the booms would be close enough to you in the seat that you could easily rotate them away from tractor out towards a sapling. and at very end of the boom. the pipe for water would be a 90 pointing down and a short piece of pipe. near you would be a LP or nature gas shuf off valve. and the water line would be 1" pipe. valve on each side (one for each boom)
i say lp or natural gas shut off valve, due to it only takes 90 degrees between fully opening and fulling closing the valve, and the handles are large enough to easily grab on to. and if not, on most of the valves you can undo a nut. and put your own custom made larger handle on the valve.
perhaps a metal bracket over rear fenders. and a rod welded on sticking up. boom placed over the rod to allow it to rotate. ((boom = A frame but on its side))
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if you are on a well
for quicker turn arounds on refilling tank. might suggest setting up a secondary tank above ground, near your source water. and putting an "auto fill valve" in it. for say cattle watering tank, or epdm liner pond to keep same water level all the time or for a pool to maintain a water level.
then place another valve (ball valve, gate valve, regular gate valve (example garden hose hook up on side of your house) between auto fill valve and source water. and turn it down some so it only dripples water in.
this will allow this secondary tank to slow fill up over the night / day. and allow the well to keep up with the flow, without a lot of worry of possibly running the well dry. when it comes time to refill the tank on the trailer. hopefully this secondary tank sits high enough, that you can plumb in a 2" pipe into the bottom of it. and just let the water gravity flow right into the tank on the trailer. and within a few minutes you will be ready to go back watering trees.
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another option, i know you hated idea of running pipe down and around trees, i also hate any sort of spirnklers or nozzles that can easly get plugged up. i allways end up muddy, cleaning them up.
Koiphen.com a good amount of folks there have 100 gallons to 1,000 gallons of water that needed to be dumped in a quick order, when they clean there filters once a week on there ponds. a good amount folks there have created there own. watering setup to water trees and yards and bushes.
many of them will install 1" to 3" pipes around the yard as mains. and then run short pipe near were they want, and then use a short peice of black plastic pipe, with some holes in it, either created by running pipe over a table saw, or drilled holes into the pipe with a regular drill / bit.
if they were good, most of them never needed to use a valve, and if they wanted more water in a certain area, they would just drill another hole into the pipe. if they had to much water in a given area, they were in trouble. and may need to replace the pipe. or perhaps use a tire patch kit. or something to push some rubber in a hole to plug it up.
the reason for the slits in the pipe or drilled hole. were due to the water was fish poo, and other muck that came out of there filters. and this muck would quickly plug up sprinkler heads and like. and the slits in the pipe or drilled holes in the pipes would not clog up and if they did not as quickly. and easier to clean with just a nail being picked into them, or like.