For those that love the outdoors, and Scottish countryside, Rob and Gabrielle Clamp’s business sounds like an ideal job. Rob, a professional forester, and Gabrielle, a herbalist, have an intimate knowledge of Scotland’s forestry and set up Birkentree in 2017.
The couple spend a few weeks in the spring tapping Birch trees in an ancient Perthshire woodland to harvest the sap, known as birch water. It’s tranquil and mindful, but not without its difficulties, as Rob explained: “The harvest period is only about four weeks and we’re really busy as we harvest by hand and in all weathers.”
The trees are tapped, where a small hole is drilled into the trunk, and a bag with a tap fixed there. Some trees produce a lot of sap whereas others don’t, and it’s hard to know how this process will go.
Rob said: “Some trees can produce about 10 litres overnight whereas others can take longer to produce a litre. There’s no way of knowing until you drill them and the sap comes out.”
The practice is ancient as are the trees - some of the bigger trees that Rob and Gabrielle tap are about 300 years old, and it’s the health benefits of the sap that has kept Birch tapping going. Drawn up through the tree’s capillary structure, it’s converted into mineral-rich water to enable the tree to come back into leaf again. Birkentree carefully hand tap the trees and collect the precious birchwater, taking less than 2 percent of the tree’s liquid.
“In March the sap is rising up the tree, which means we can harvest it. As a drink, it’s very good for you. The sap is enriched with minerals and vitamins, enzymes, antioxidants - everything that the tree needs to get back to life,” Gabrielle explained.
Rob and Gabrielle are, so far, the only producers harvesting Birch sap in Scotland as other producers import theirs from Latvia and Finland. And it was discovering this that led Rob and Gabrielle to set up Birkentree.
Rob said: “We discovered that, after buying a bottle, that all the birch water on the planet comes from Scandinavia, and the Russian states. And I thought, well, that's mad. In this day and age with local produce being favoured and wanting to reduce air miles and carbon footprints, we want to put Scotland on the map for birch water.”
The area they’re in is no coincidence either as ancient Scottish birch trees are unique to Birkentree’s geographical position - Perthshire - climate and topography. “In Scotland and particularly in the Highlands of Scotland, people would tap Birch trees in springtime because they knew that there were lots of minerals and enzymes. They would kind of drink it as spring tonic,” Rob said.
The couple rotate which trees they tap. “We tend to not come back to the same trees but in America, where they tap Maple trees using the exact same process, they go back to the same trees year on year. We probably could if we wanted to, but we have plenty of birch trees so we don’t need to right now” Rob said.
Once the harvest is done, the team re-plug the small holes in the trees with birch wood.’ This process, the couple say, is sustainable, non-invasive and harmless to the tree itself.
While the birch sap is the main component of Rob and Gabrielle’s business, the entire birch tree has health properties, as Rob explained. “We'll go into picking birch leaves in early May or late April. You can use the leaves to make a really nice nutritious tea.
"You can also put them in a bath as birch is very good for the skin, some skincare companies use birch leaves. You can make birch oil, treat cellulite and the like as birch helps rebuild collagen in the skin.
"We can use the buds and the bark, they are incredible trees. We're not inventing something new. This is just reviving old traditional skills and knowledge that's disappeared over the years.”
The trees themselves are an ecosystem in themselves, with the older ones being covered in lichens and mosses that support hundreds of insect and vertebrate species. Therefore it’s important to preserve the trees, and look after them, something Rob and Gabrielle are passionate about.
As it is the birch sap that is the main focus of Birkentree, what does it taste like? Rob said, “it has a light consistency with subtle, smooth layers and a delicate complexity.”
Up until earlier this year, the couple had been selling the plain water and were set to launch a sparkling version. Many high end restaurants were stockists and customers can buy the water online.
In mid 2021, after investment from local partners, Elspeth and Euan, Birkentree’s focus shifted to being a natural accompaniment to whisky.
Rob said: “Bringing Birkentree to life has been an exciting journey. We have always believed that birch water’s smoothness meant it had the potential to become a natural companion for whisky - from a peaty dram from Islay to a fragrant Scotch from Speyside.
"We know that whisky drinkers, whether single malt enthusiasts or people trying their first dram, will love Birkentree from the very first sip.”
The Birkentree team recommends its birch water is served slightly chilled and shaken vigorously ahead of opening - this brings to life the subtle and delicate accompaniment, ready to pour.
Whisky accompaniments have become all the rage recently, from chocolate to savoury biscuits and waters, so why birch water and not that which flows from the tap?
Rob and Gabrielle say that birch water adds a complexity that water alone cannot match. “Water is thin and dilutes the whisky, whereas our Birchwater leaves a smooth mouth-feel which complements the palette, allowing you to experience the unadulterated layers within fine whiskies.”
Those that worry that the birch water will overwhelm the whisky need not worry as Rob explained “it accentuates the flavour profile of fine whiskies; Birchwater is subtle and delicate, making it the perfect pairing for whisky.”
Birkentree’s dedicated whisky expert Max McFarlane, recommends that the optimum ratio is 50:50, however it is all down to personal taste.
While the business has grown, the birch trees and a sustainable ethos is still at its heart, as Rob said: “we always wanted a project and business that fitted with our kind of ethos of sustainability and health and traditional skills and knowledge, and Birkentree is a perfect fit for that.”
Birkentree Highland Birchwater is available to purchase online for £5.95 (100ml) from their website.