Turn Sugar Tree Sap Into Syrup

Making syrup at home is easy with the right tree sap.

tapping a tree for sap

A sugaring sap pail hanging from a spile driven into a sugar tree.

Photo By Shutterstock/brm

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Most folks have heard of maple syrup, and in some areas pecan syrup is still fairly common. But today few people are aware that walnuts, hickories, sweet birches and even sycamores can produce similar products. Only a few old-timers and wild-food enthusiasts still go the extra mile and further process the syrups into sugars, but during much of our country’s history, sugaring produced an important part of the family food supply. For the curious and would-be self-reliant, it still can.

Meet the sugar trees with the best tree sap

Any maple large enough to tap will produce syrup and sugar. Historically, folks used all native maples to some extent. Today, most maple syrup comes from the sugar maple, the closely related black maple (now usually regarded as a variant of the sugar maple), and the box elder or ash-leaved maple (heavily used in Canada). Maple sap is usually about 2.5 percent sugar. However, maple saps with a sugar content of 5 percent or more are not uncommon, and the record for sugar content is about 9 percent.

In general, the saps of trees with large crowns, such as lawn trees, will exhibit higher sugar content than that of forest-grown trees. Considerable variation in sugar content and sap production is found among species and individuals within species. Seasonal characteristics also can affect the amount and quality of sap produced by an individual tree from year to year.

Sugar maples have a relatively high average sugar content in their sap. But the closely related black, southern sugar (also known as Florida or hammock maple) and big tooth maples are at about the same level. Box elder, red maple, plane tree maple and big leaf maple are close behind.

Many old-timers considered the silver maple a poor producer or, at least, a producer of inferior products with an off flavor. Most of the silver maples I’ve tapped were lawn trees, and I’ve found them to be competitive with any of the others.

On average, the highest sugar levels are found in Norway maples, an imported species. This is probably because in North America they are used mostly as specimen trees, but it is still a good showing for a tree that has been dismissed by some as not worth using.

When they get large enough to tap, small maples like mountain and striped also produce good products. The small southern, western and imported maples — such as chalk, vine, Rocky Mountain, English field, full moon, Amur and Japanese — also can be utilized when they are large enough.   

Walnuts (Juglans spp.) and hickories (Carya spp.), except for pecans (pecans are part of the hickory group), are probably the least remembered sugar trees, but they didn’t fall from favor because they produce inferior products. All members of the walnut and hickory clans produce good sweets, even those that produce inferior nuts.

The black walnut and the butternut, or white walnut, produce earthy distinctive syrups and sugars that some prefer even to the maple products. Hickory syrups and sugars are very good sweets but not as distinctive as those of the maples and walnuts. All walnut and hickory species are good sugar trees, including the Eurasian species. The only members of this group from the Old World that I’ve had the chance to try are the Persian or English walnut. They produce sugars and syrups that are more like our hickories than our walnuts.

Other than maple and pecan products, the best remembered sweets from trees come from black birch and yellow birch — the sweet birches. The sweet birch saps have a sugar content that is roughly half that of maples. However, birches make up for their relatively low sugar content by producing copious sap flows.

This is true of the other birches as well, but their sugar content is so low that syrup production is not practical.

Sweet birches share an essential oil with the wintergreen plant. Today, commercial wintergreen flavoring is usually artificial, but natural wintergreen flavoring is generally distilled from the sweet birches, not the wintergreen plant. This essence is very volatile, and some folks add birch twigs to the boiling sap just before the syrup is finished to ensure the retention of this characteristic flavor.

Sycamores are the last group of historic sugar trees. The boiling sap gives off a maplelike scent, but most people find the finished products inferior. Euell Gibbons, the wild-food proponent of the 1960s, compared sycamore syrup to low-grade black strap molasses. I think that is a bit harsh — it is more like badly scorched maple syrup. I’ve known people who have had fair results by mixing it with other saps, and modern evaporators might produce a better pure product. However, when other saps are available, sycamore syrup is hardly worth the effort.

Getting sappy with sugar trees

It takes 30 to 50 gallons of sap — depending on such variables as conditions, the species or multiple species involved, and the individual trees — to produce a gallon of syrup. Sweet birches take about twice as much, and sycamores even more — much more.

Sugaring is best on warm, sunny days after cold, frosty nights, while things are thawing but before the leaves appear. In Pennsylvania, the season usually runs from late January until early April, but may start earlier in mild winters and much later if the winter is brutal. Production may also be interrupted by arctic outbreaks.

Maples reach peak production first, followed by nut trees and finally the sweet birches. Generally, production starts first in the low country and lasts longer in the mountains. While peak production may vary, all of the sugar trees produce for most of the season.

Some areas can produce a variety of syrups and sugars. Some old-timers tapped any sugar trees at hand, combined the saps, and called the results sweet or simply maple syrup after the sugar trees that predominated in most areas.

The taps for collecting sap are known as spiles. Traditional spiles were often made from elderberry canes. Cut some large canes into 4- or 5-inch sections, remove the pith with an iron rod, sharpen one end slightly, cut a notch on the top side near the other end, and you are ready to sugar.

Although it is harder to work (but more durable), small branches of staghorn sumac and its close relatives can be used in the same way. Homemade spiles generally require larger, deeper holes than their commercial counterparts.

While it is nice to know how to do it yourself, smaller holes heal more quickly, so there are advantages to commercial spiles. I’ve used metal spiles in a number of patterns. Although I’ve never used them, plastic spiles that are even smaller than most metal spiles are available. If you want to use commercial spiles and your local hardware store doesn’t have or cannot get them, sugaring equipment can often be found in catalogs and advertised in publications that are aimed at homesteaders.  

Once you have your spiles, take a drill with a bit sized to those spiles and drill holes slanted slightly upward into your sugar trees. The depth of the holes range from 1 to 3 inches, depending on the thickness of the bark and the size of the spiles.

Tap the spiles into the holes. You want a snug fit, but you don’t want to seal off the sap ducts you just opened. Now start collecting sap.

Traditionally, buckets were hung on the spiles. The buckets are usually covered or fitted with flaps to keep dirt and other unwanted materials out. Plastic spiles are made to use with plastic tubing that can run to a large container serving all the spiles on one or more trees. In the case of large hillside operations, networks of tubing may carry the sap directly to a sugar shack for processing.

Taps on the sunny side of the trees are most productive. A tree you can reach around with just your hands, thumb to forefinger, can take a single spile. A tree 1 foot in diameter can take two spiles. Very large trees can take numerous spiles, and they should be kept about a foot apart. At the end of the season, many old-time sugarers would plug the spile holes with warm paraffin to stop the loss of sap and deter ants and other insects from being drawn to the wounds.

You can collect sap for a small batch of syrup without spiles. Clip the ends off of low branches, stick those ends into plastic milk jugs or similar containers, and tie them firmly in place. Anyone who has ever licked the late winter icicles that form on broken birch and maple branches will get the idea.

Boiling it all down and making syrup

Unless you have a commercial evaporator, the tedious part of sugaring is boiling down the sap. Even the evaporators have to be watched. The process seems to take forever. Then, when it starts to reach the proper consistency, it can quickly boil over. Watch closely and stir as needed. If the thickening sap starts to stick to the sides, your products may have a scorched flavor. Old-timers kept the boiling sap quiet with a dab of butter. Just don’t let it get too hot. Maintain a gentle boil. Syrup reaches the point where it can be stored without spoiling at 7 degrees above the boiling point. Taking it to a higher temperature will give you a thicker, more concentrated product. Sugar is done at 22 degrees above the boiling point.

The boiling point is influenced by altitude, so note the temperature that the sap starts to boil at your location, and add the appropriate number of degrees to know when your products are done. Once it has started to cool, syrup can be decanted into clean glass jars or jugs. It should be well-cooled before putting it into most plastic containers. Sugar should be poured into greased bread pans or similar containers while still quite warm.

Modern equipment is nice, but lots of syrup and sugar have been produced by primitive means. So whether you want a single batch or a year’s supply, a range top or even an open fire can be pressed into service. At one time, a butchering kettle or several of them were used to produce all the sugar and syrup a family or group of families would use in a year. For some folks, they still do it this way, or they will do a single batch or two.

If you are going to use a range top for more than a gallon or two of syrup and perhaps a batch of sugar, that unit should not be in your kitchen. It does not take long for boiling sap to make everything sticky. Sugar shacks aren’t just to get your production near the sugar bush, but also to get it out of the house. I’ve seen several people using covered fireplaces in open picnic shelters.

To your health

Maple and sweet birch saps are not only the raw material for making sugar and syrup but also traditional spring tonics. It stands to reason that when fresh foods were not available in the winter, these raw saps were important sources of nutrients. Unlike many tonics that you have to grin and bear, sugar saps are usually consumed with relish, even though the sugar is so diluted in most saps that it can’t be detected by taste. I can’t resist a good drink of sap when sugaring. Try it once, and you’ll be hooked for life.

Health-food advocates and even some wild-food enthusiasts have disparaged syrups and sugars from trees as being just as refined as commercial sugars. This is not true — these sweets are concentrated, not refined, and like their saps, they contain good levels of antioxidants. Sweets you can feel good about!

Other traditional spring tonics, like sweet birch, sassafras and spicebush teas, were considered best when brewed in sugar saps. At the right time of year, any sugar tree can be a practical source of pure drinking water. It’s important to remember that you don’t have to live in a sugaring area or have acres of woodland to make syrup — all you need is a maple, walnut, hickory or birch tree in your yard, a bucket, and a spile.  

Read more: Freeze sap for (nearly) effortless syrup in How to Make Maple Syrup at Home from Mother Earth News magazine.

Craig Russell grew up sugaring trees near his home in rural Pennsylvania. He is currently the president of the Society for the Preservation of Poultry Antiquities, but his enthusiasm for the old ways of doing things certainly doesn’t end with poultry.   

Scientific names of sugar trees

American Sycamore, Platanus occidentalis 

Box Elder (also Ash-leaved Maple), Acer negundo                 

Sugar Maple, Acer saccharum 

Black Maple, Acer nigrum 

Southern Sugar Maple, Acer barbatum Michx. (also Acer floridanum)

Red Maple, Acer rubrum 

Planetree Maple, Acer pseudoplatanus 

Bigtooth Maple, Acer grandidentatum 

Big Leaf Maple (also Western Maple), Acer macrophyllum 

Silver Maple, Acer saccharinum 

Norway Maples, Acer platanoides 

Mountain Maple, Acer spicatum 

Striped Maple, Acer pensylvanicum 

Rocky Mountain Maple, Acer glabrum Torr.

Chalk Maple, Acer leucoderme 

Vine Maple, Acer circinatum Pursh

English Field Maple, Acer campestre 

Full Moon Maple (also Shirasawa’s Maple), Acer shirasawanum                                     

Amur Maple, Acer japonicum Thurb.

Japanese Maple, Acer palmatum Thunb.

Black Walnut, Juglans nigra 

White Walnut (also Butternut), Juglans cinerea 

Persian Walnut (also English Walnut), Juglans regia 

Black Birch, Betula lenta 

River (also called Black) Birch, Betula nigra 

Yellow Birch, Betula alleghaniensis  

Talk like an old-time sugarer

Sugar tree: A tree that provides sap for making sugar and syrup.

Sugar bush: A group or concentration of such trees.

Sugar shack: A building with the facilities to produce syrup and/or sugar.