Birch (Betula) forms its own plant genus of around 100 species found across the entire Northern Hemisphere — from Europe through Russia and Asia to Japan and North America. Birches are often pioneer plants, thriving on both dry and wet soils, in heathland, on dunes, and in bogs — even on buildings and ruins. Alongside aspen and pine, they were among the first trees to form forests after the last Ice Age.

To this day, birch remains a tree used almost everywhere in both magical and everyday life: as the classic maypole and in Corpus Christi processions, for making brooms and birch tar, as a protective tree marking accident-prone, unlit road bends — since pale birch bark remains visible even in dim light — as a symbol of fertility and an ingredient in medieval sexual-magical practices, and for making antiseptic bread boxes. Xylitol, the sugar derived from birch sap, has seen renewed popularity in dentistry for its cavity-fighting properties; the lower layer of birch bark is even edible and can be prepared like spaghetti. The Brothers Grimm's German Dictionary describes it thus: "The birch is a tree of joy and of grazing shepherds, with whose leaves they adorn themselves, in whose shade they rest, into whose white, soft bark they carve names."

Burned as incense, birch releases a bright, resinous-sweet, faintly smoky scent. It is associated with cleansing, new beginnings, and the strength of the first spring light, long considered a tree of renewal after winter.

Amber (from Middle Low German "Börnesteen," meaning "burn-stone") is a fossilized resin originating from an extinct plant species not yet conclusively identified. By far the most common type of amber is succinite, of which an estimated 640,000-plus tonnes still lie in the ground in the Baltic region alone. Aristotle already suspected a botanical origin, though it was not until the mid-18th century that Russian scholar Mikhail Lomonosov provided scientific proof of amber as fossilized tree resin.

For thousands of years, amber was worked into jewelry in the Baltic region or exported as a raw material to the cultures of the Mediterranean; in Egypt, crafted objects of Baltic amber over 6,000 years old have been found, and Emperor Nero consumed it in vast quantities. Through friction, amber becomes electrostatically charged, and was thus used in antiquity to clear dust particles from the air — the ancient Greek word for amber, "ḗlektron," is in fact the origin of our word "electricity," and the Baltic islands from which the old amber roads led south were known in Greece as the "Electrides." Its extraordinary properties — flammability, translucence when polished, electrostatic charge, coloration — made succinite a mythical stone in many cultures: the "gold of the North," the tears of the Heliades, the amber castle of the Lithuanian legend of Jūratė and Kastytis. To this day, much as in India and in Sufi rituals, it continues to be burned as incense for its fragrant essential oils.

Amber also frequently contains inclusions of extinct animal and plant species — roughly 4,500 per tonne in Bitterfeld succinite — which have fired the scientific and poetic imagination from antiquity to "Jurassic Park." The Roman poet Martial wrote of this in his epigram "De ape electro inclusa" ("On a Bee Enclosed in Amber"): "The bee is seen, and shines enclosed in amber, so that she seems preserved in her own nectar. She could not find a nobler tomb to die in, and, dying, may have wished for this alone." Burned as incense, amber releases a warm, resinous-sweet scent with a subtle, faintly animalic depth.