Make your own maple syrup without harming the trees

maple syrup

Maple syrup ready for pancakes and waffles. LadyDragonFlyCC via Wiki

This story was originally featured on Outdoor Life.

There are windows of opportunity in nature, and one of my annual favorites is “sugaring time.” In late winter, tree sap begins to flow, and from the right trees, this sap can be collected and concentrated into a very special (and very delicious) caloric resource—sweet tree syrup. Most of us focus on how to make maple syrup during this window. But maple trees are just the beginning. Here’s what you need to know about the history of tree tapping and the basics on how to tap trees for syrup.

A quick history of tree tapping

There are many legends surrounding the discovery of maple syrup in the American Northeast. One of my favorites involves a Native warrior practicing with his tomahawk. After sticking the axe many times into a sugar maple tree in early spring, his wife noticed the water running out of the trunk. She gathered this water and prepared a soup—which turned out to be surprisingly sweet. After a little experimentation, maple syrup was born.

While it seems likely Native Americans independently discovered that tree saps can be boiled down into syrup, the idea that tree tapping is a unique skill of the First People of the New World just isn’t accurate. Tree sap was collected and used as a food and drink resource in many parts of the Northern Hemisphere for more than a thousand years (and not just in the boreal regions). The Arabian explorer Ahmad ibn Fadlān documented the Bolgar people collecting birch tree sap near the Volga River and fermenting it into an alcoholic beverage in 921. For many centuries, in fact, birch sap has been consumed fresh as drinking water, boiled down into a sugary syrup, and converted into a wine-like beverage in Russia, Scandinavia, Ukraine, Poland, Slovakia, Belarus, Estonia, Latvia, and several other European countries.

tree syrup
It’s a common misconception that the only tree syrup comes from sugar maple and the only places it can be made are the American Northeast and Canada. TIM MACWELCH

How tree sap flows

Throughout the Northern Hemisphere, you’ll see trees with running sap between January and early March each year. Specific timing depends on the weather, latitude, elevation, and the tree species you are working with. Some of these trees can be sources of water if you get caught outside without anything safe to drink. Other trees can provide delicious syrup. This sweet treat represents life-saving calories at one of the roughest times of the year for survival, but it’s also great for everyday culinary uses.

Most tree tappers know that the sap flows best in the late winter, when the nights are below freezing and the days are above freezing. What is not commonly known (by non-botanists) is how the sap actually flows. During the late winter and early spring of each year, the water inside the tree has greater pressure in the roots than at the crown of the tree. This greater pressure pushes the water up toward the crown, carrying some of the sugars that were stored in the tree roots. Since this internal water pressure is higher than the atmospheric pressure, any hole in the tree bark will allow sap to flow out of the tree rather than continuing to flow through the tree.

tapping trees
Tapping doesn’t harm trees, as long as it’s done carefully. TIM MACWELCH

How to tap a tree

Drill a hole through the bark, about 2 inches into the sapwood, angling the hole upward. Any reasonably sized drill bit can work, but many folks go with a 7/16 inch hole, which matches the commercially available tree taps known as spiles. Once you’ve drilled your hole, you can hammer in a spile and hang a bucket or jug on it to collect the sap.

If you can’t find a supplier for spiles, use whatever you have. Half-inch vinyl tubing works well, as will bamboo, PVC pipe and metal pipe pieces. All you really need is something to channel the sap to drip into your container. Plastic drinking water jugs are fine for sap collecting, as are the classic little metal buckets. In recent years, I’ve started using plastic vinegar jugs. These vinegar jugs are thicker walled and stronger than water jugs. This keeps your jugs from bursting due to freeze expansion. Does tapping hurt the tree? In short, the answer is no, as long as you don’t plunge your tap deeper than 2.5 inches, where it is possible to hit the heart of the tree.

tapping trees
With a cordless drill (or an old fashioned brace and bit), you can drill into your sap-producing trees and begin collecting their sweet nectar. TIM MACWELCH

Choose your trees for maple syrup and more

Maple syrup is certainly the main tree sap sweetener in the world, and it’s known and exported worldwide. The sugar maple isn’t the only tree species that can provide us with tasty syrup. Sycamore trees (Platanus occidentalis), birch trees (the genus Betula), and hickories (the genus Carya) can also be tapped for drinking water or boiled for syrup. Black birch is particularly delicious, with a rich flavor similar to wintergreen.

Walnut trees (the genus Juglans) are another option. These can be tapped for drinking water at the end of winter, or the sap can be collected and boiled down into syrup. Here’s the odd issue, though. Walnut trees have a small amount of iodine in the nuts and in their sap. When reduced and concentrated, the finished walnut syrup is sweet, but it also bears a slight bitterness that is briny, kelp-like and almost fishy (from the iodine). For that reason, walnut syrup is not particularly popular and is regarded as inferior to maple. But if you’re looking for something different and you use fish sauce in your cooking on a regular basis, you might like it. Otherwise, you may want to skip the walnuts for syrup production (and you’ll definitely want to skip them if you’re allergic to walnuts and other tree nuts).

Tips for tapping trees

While these tips are most commonly used with maples, they can also help you when tapping any species of tree.

  • You’ll typically get the best sap flow on the south side of the tree (in the Northern Hemisphere), since that side has the most sun exposure and is naturally warmer.
  • Put in one tap for each foot of diameter on the tree trunk.
  • Younger trees are often more productive than older trees.
  • If you’re using it for drinking water, drink it within a few days. The sap doesn’t keep long without souring.
  • Treat sap like milk—keep it cold, keep it clean, and do something with it sooner rather than later.
  • If the sap has turned cloudy and smells sour (usually after sitting for more than one week), it has become a breeding ground for bacteria and should be discarded.
  • Collect your sap each day to avoid overflowing containers and wasted sap.
  • The sap doesn’t run the same every day.
  • Make as many taps as you can, to make this venture worthwhile.
boil tree syrup
With a large pot and some kind of heat source (either an open fire or a propane cooker), you can boil your sap outdoors (and keep all that steam out of your house). TIM MACWELCH

How to boil tree sap

With the largest pot you own and a reliable heat source, you can head outside and start boiling whenever you’ve collected “enough” sap from your trees. Boiling indoors is never a good solution, as every surface will soon be covered with condensed water. Boiling can be achieved over a wood fire or propane burner. Bring the sap to a boil and keep it boiling until it visibly thickens. It should look like new motor oil (in color and viscosity) when you are close to finishing. Dip a spoon into the syrup and pull out one spoonful of this amazing tree sugar. Allow it to cool for a moment and then see how it pours. If the syrup forms a curtain-like sheet off the spoon edge, you are done. If it is still runny, boil off more water. Be aware that there is a fine line between too watery and too dry. If you overcook the sap, it will crystalize into a solid upon cooling. This is fine, if you’re trying to make maple candy, but most people prefer syrup.

After hours and hours of boiling, you may get a tired of watching your cauldron bubble, but don’t give in to the temptation to wander off and work on some other project. If you leave your boiling pot unattended and the liquid level gets too low, it’s very possible to scorch your tree syrup. I know, I’ve done just that. The over-cooking of sugary substances has given the world some tasty treats (like toffee, for example). But if this over-cooking goes a shade too far, you’ll end up with burnt syrup that has a harsh and bitter flavor. Don’t waste hours of tapping, collecting and boiling. Watch your sap like a hawk as you near the end of the boiling process. If the scent changes and/or the color darkens quickly, pull the boiling pot off of the heat immediately. You’ll thank me for it.

Know your maple syrup numbers

A really friendly sugar maple tree may yield sap that is almost 5% sugar by volume. This is potent enough to really taste the sweetness in each drop of sap. Other trees, however, just aren’t that generous. Some of the other maple species and other “tappable” trees may barely give you 2% sugar by volume. This is still worth using for syrup, and it’s certainly worth boiling for syrup, but you’ll need a lot more sap. With sugar maples, you’ll need 10 gallons of sap to make one quart of syrup. If that sounds like a lot, don’t worry. Each tap into a productive tree can yield one gallon of sap per day at the height of the sap run. This means you’ll only need 10 taps to produce a quart of syrup each day of the peak sap run. Regardless of the species used, once the sap is reduced to syrup, it has about 100 calories per ounce.

How to store homemade syrup

Commercial syrup production has many standards and one of those is the percentage of water left in real maple syrup (and other tree syrups). This is nearly impossible to measure in a home sugaring operation, and we tend to leave too much water in homemade syrup. This does give us the illusion of greater volume, but it’s also a point of vulnerability. That water can allow your hard-won syrup to mold. One quick fix to prevent molding syrup is to store it cold. By keeping it in a refrigerator, you’ll buy yourself plenty of time before the mold starts to grow. An even better approach is to use a water bath canning technique to store the syrup in jelly jars. There’s no need for pressure canning, since the sugar content is so high in syrup (very sugary and very acidic foods don’t require the intense heat and time of pressure canning). Ordinary water bath canning is all you need. Process the syrup filled jars just as you would when making jam or jelly, and your sweet syrup will last for years.

How to brew maple wine

I’m not the first one to do this, but I’d like to think I got the inspiration from the same source as our ancestors. One of my all-time favorite home brewed beverages is something I call maple wine. Having been a home brewer for about a decade now, I really enjoy new discoveries. I knew that the American founding fathers used maple syrup in certain beer recipes, and I’m also a big fan of mead (which is an ancient wine made from honey). On a whim several years ago, I put these two concepts together when I took some of my red maple sap out of the syrup boiling process and turned it into wine using my standard mead-making process. Here’s a quick rundown on the process for the best homemade wine I ever made.

1. Reduce 10 gallons of maple sap into one gallon of sugary fluid. Check the sugar content with a triple hydrometer (if you have one). The specific gravity should read 1.100 or near that mark. If you don’t have this brewing gizmo, just hope for the best.

2. Allow the sappy syrup water to cool to room temperature. While this is happening, sanitize a one-gallon glass jug with vodka or home brew sanitizer. Also sanitize a stopper and wine lock that fit the jug. These are available where homebrew supplies are sold.

3. Pour the syrup water into the clean jug and add a small packet of red wine yeast. This is available where the other supplies came from. Plug the jug with the stopper and a water-filled wine lock. Keep the jug in a dark place, with a steady temperature between 60 to 70 degrees for the next two months. It should bubble for weeks and finally start to settle down after a month and a half.

4. Finish the wine. After two months, gently pour the wine off the sediment into a new clean container, leaving the sediment behind. If the wine hasn’t cleared, add a hot wine finings mix (from a home brew shop) and wait one week. Pour off the sediment again. Bottle and age this amber colored nectar, or drink it right away. This dangerously smooth, silky wine should be almost 20 percent alcohol by volume and taste of maple and caramel.