Back in the early ‘60s, we were making syrup pretty much the same way Great Grandma, one of those NY Yankees come to Wisconsin, made it in Maple Grove Township near Barron WI. She married a green Swede, just barely off the boat, and taught him to make syrup with buckets, spiles and a big round kettle, that doubled for making soap and scalding the hogs.
We had upgraded to a flat pan, a hundred 3-gallon cherry tins (from the bakery), and metal spiles, getting them from Norman Anderson over at Cumberland. “Have you heard the latest,” Norman told us when we got some supplies that year, “some folks have taken to hooking up the milking machine vacuum pump and tubes or pipes to the maple trees and suck the sap out. They get more sap.”
Well, that was sure something new! We milked 25 cows on the farm, and maple syruping was more of a hobby those days than a business, so Dad wasn’t much interested in tubing.
Already at age 14, I was planning to become a scientist. I had a telescope, microscope, chemistry and electronics kits and thought science was everything. I was feeding old Brahma, the boss cow with the strange hump, more and more grain, keeping track of the milk production to see if it was profitable.
We had a lovely large sugar maple in the hard between the house and barn, It was our best shade tree—probably 100 years old and at least 3 feet in diameter. We put 5 buckets on it every year, and it gave the sweetest and most sap of any tree in the woods nearby where our 100 buckets hung.
Well, being intrigued with the idea of vacuum on a maple tap, I just had to try it. I found the long garden hose and put on a fitting to hook it to the milker pump vacuum line, ran it to the tree and rigged up a tap that hooked to the hose without any vacuum leak. The vacuum line ran to the milkhouse where I hooked it to the step-saver bucket so the sap would come in directly to the bucket from the tree.
After the morning milking, I hooked it up, with Dad skeptically watching me to make sure I didn’t mess up his milker system. The vacuum line check valve ran at 15 psi for milking cows. I left it at that, turned on the vacuum pump and watched. The other 4 pails were dripping slowly that morning. In my vacuum tank, I could see through the clear tubing at the step saver, that sap definitely was coming in at a faster rate! It worked! Even Dad was impressed!
Well, sometimes a scientist must experiment more. “I wonder what will happen if I bring the vacuum up to 20 psi,” I thought and then followed through tighting down the check valve watching the pressure creep up to 20. Sure enough, the sap was now running a tiny stream rather than just the drips, looked like double the rate of the pails.
I got the big pipe wrench and tightened the check valve down as far as it would go. The pressure gauge rose to 21, 22, 23,… and soon pinned at 25, while the pump motor strained to pull the vacuum deeper and deeper. Sap gushed into the step-saver.
All of a sudden I heard and explosion outside. I shut off the pump and rushed outside to see what had happened.
The tree was there, but didn’t look like a tree at all. It looked like nothing I had ever seen before. Dad, who was in the middle of his morning wheat bisquits, had rushted out too. After studying things, he said “Man alive Russell, you must have put so much vacuum on that poor tree, you sucked it inside-out! You and your science experiments have ruined our best shade tree! No more monkeying with the vacuum pump.”
I never felt the urge to try vacuum on a maple again. However, an interesting thing happened. The tree, besides being inside out, was dried out and when I took the chainsaw to cut it up, the chunks just fell apart into nicely split sizes. It was ready-made for burning!
I did try this later on an old oak, thinking I would get firewood in a hurry with that too, but it was so filled with holes, squirrels and birds, the step-saver bucket kept plugging up with them and I really couldn’t get much vacuum with the leaks. I patented this method for making firewood, but recommend it only for younger trees that are still sound!
Those of you trying for high vacuum on your maple tubing lines, should take care when you get over 25 psi, and remember my experiment or you might turn your whole sugar bush inside out. Maples inside-out probably look just as ugly as one of us would look with our insides on the outside.
I did go on to be a scientist. However, I was always careful in my experimentation to never push things to the limit. If you don't learn from your mistakes, you are not a very smart person!