TJ,
I have some experience at this macro injecton via the main stem, injecting Amer. elms against DED.
The system I bought was basically a stainless steel hand pump type sprayer with a regulator valve to contol the pressure. I can take a pic for you and try to dig up the manufacturer, but it will take me some time to dig up the info. I know I didn't throw out the information that came with it.
If memory serves me right, the system I have only requires about 10 to 15 lbs pressure, you don't want to much pressure. With too much pressure you could blow out the bark or damage the vascular system in a tree or pop those tees out.
Anyway, just from my experience, you can't force feed a tree if conditions are not right. Timing is everything, in a nutshell, early morning just before sunrise or shortly after is the time to start the injection. For the injection to work there must be ample soil moisture, a forecast for a sunny day, with low humidity conditions, light beeze, I always had the best luck with a north or north east breeze. Time of year is also important, I never did a tree in late spring, but June, July, August for the most part are lousy months, I had good luck mid September to mid October.
FYI, I know this is a off the wall big time, but I have taken a five gallon pail, put a gate valve in the bottom of it, no leaks of course, hung it on the tree with the chemicals mixed, connected the hoses and tees and let the tree and gravity do its thing. If the patient is willing it does work.
Larry
