230 Murmuring firs of Kielder Forest

Fir trees don't have what you might call normal leaves. Their leaves are needles. Each tree possesses many needles, too many to count. Especially when the height of these trees ranges from 12 to 23 stories high. Concentrated in these myriad tiny needles, is a wonderful and special power. Position yourself deep within a fir forest, with even the slightest of breezes blowing high above, and you'll feel it.

You'll notice it first as a sound in your ears, but that is only where it starts. The softest, the most velvety, the most spatially rich sound imaginable. Without realising it, the sound passes from your ears to become a sigh In your chest and lungs. Further it flows, permeating through your whole body. The more you tune yourself into the sound of the fir trees, the more you still your own motion, the more you detach from the need to think of anything else, the more the waves of relief flow. The sensation is real, a palpable response to the aural awe diffusing down into the spaces beneath the firs.

Fir trees we feel create such powerful and yet enchantingly delicate sounds, that since experiencing them high in the hills of Dentdale last summer we knew we had to try to capture more. More fir trees in more different contexts, across more ground. That meant we had ultimately to go to the Kielder Forest, the largest fir plantation in England.

This sound capture is from a location in the Kielder Forest called Forest Drive. After reaching the area and then following rough tracks cut through the forest over several miles, we reached a place where a huge section of plantation was visible processing down the valley. Row, after row, after row of tall fir trees. The effect was enchanting, and fixed us to the spot. As we stood looking the wind began to rise in the treetops. The sound came. Velvet brown waves, of physically rejuvenating sound. It took our breaths away.

If you are able to find a quiet and still spot to listen to this episode with a pair of good headphones or Airpods with noise cancellation, the Lento microphones have managed to faithfully capture quite a lot of the aural perfection that existed inside this huge forest, on that warm and blowy spring day earlier this year.