This section is from the book "The Gardener's Monthly And Horticulturist V20", by Thomas Meehan. See also: Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long.
Vanillin exists in the sap of the pine (Pinus sylvestris) and of the larch. For the purpose of procuring it, the trees are felled during the period when vegetation is most active, and are stripped of their bark. They are then immediately scraped, and the product collected in vessels of tinned iron, is immediately heated on the spot to prevent fermentation, filtered, concentrated, and allowed to cool and settle. A substance is thus obtained which resembles powdered sugar, and which is known as coniferin. This is a stable compound, and is sent in barrels to Paris, where the vanillin is extracted. The process of extracting the vanillin is an expensive one, but the product is procured at a less cost than the natural vanilla of commerce can be purchased at. - Scientific American.