Applied Biodynamics — Issue 067 (Winter 2009–2010)

Issue 067 is a single-preparation, method-intensive issue devoted entirely to BD 508 (Equisetum arvense, horsetail). Across multiple articles, the issue establishes material sourcing, preparation protocols, application timing, scale-up methods, and comparative field outcomes, making it one of the most procedurally explicit issues in the Applied Biodynamics archive.

In “How to Make BD #508 (Equisetum arvense) Horsetail Tea,” Patricia Smith presents a fully specified preparation protocol used at the Josephine Porter Institute. The article distinguishes between fresh tea and fermented tea, with emphasis on the fermented version due to its greater treatment capacity and storage stability. Harvesting guidelines specify cutting the stems between May and September while leaving basal growth intact to allow regrowth. Drying is carried out for several days, followed by chopping into quarter- to one-inch lengths and storage in dark, dry conditions for up to two years.

The preparation method is explicitly quantified: ten ounces by volume (approximately one and a half ounces by weight) of dried horsetail are simmered in one gallon of water for one hour, cooled, transferred to a crock, and allowed to ferment for 10–14 days. Readiness indicators are clearly defined, including the development of a sulfurous odor (“rotten egg” smell) and the formation of a surface film of spores. Storage conditions and reuse of a continuous fermentation crock are also specified, allowing reproducibility and comparison across batches.

“Fields of Gold Farm Keeps Blight at Bay with Use of BD #508,” by Patricia Smith and Hugh Courtney, documents a commercial farm case study focused on fungal disease suppression. The article situates BD 508 within a broader integrated spray program, combining it with BD 500 (horn manure) and Barrel Compound Preparation. Application timing is carefully controlled: soil sprays are applied before planting or before head formation in grains, while foliar sprays are avoided during flowering due to observed reductions in fruit set. The farm reports reduced fungal pressure under high-rainfall conditions, with yield and grain quality compared favorably to neighboring operations using conventional fungicides.

In “Sulfur Influence of BD #508 and Climate Control?” Patricia Smith explores the relationship between BD 508, sulfur metabolism, and moisture regulation. Drawing on Rudolf Steiner’s indications and field observation, the article hypothesizes that horsetail’s silica-sulfur balance contributes to fungal suppression by regulating excess moisture rather than directly killing pathogens. The article does not assert mechanism but instead correlates spray timing, weather conditions, and disease outcomes, explicitly inviting further observation and reporting.

“Kentucky Farmer Has Many Uses for BD #508,” also by Patricia Smith, presents a large-scale, multi-year case study from a 2,600-acre hybrid organic–biodynamic grain and hog operation. The farmer uses BD 508 extensively across corn, wheat, cover crops, and manure systems. Preparation scale-up is described in detail: thirty pounds of dried horsetail are brewed in a ninety-gallon cast-iron kettle, fermented for approximately fourteen days, strained, and stored in a 250-gallon tank. The spent plant material is composted.

Application rates and acreage are specified, including soil applications to hundreds of acres in spring and fall. Observed outcomes include reduced Fusarium pressure during an exceptionally wet growing season, wheat yields averaging seventy-one bushels per acre, and reduced production costs relative to conventional systems. The farmer explicitly notes limits: once plant tissue has died, fungal decomposition proceeds normally, indicating that BD 508 acts on living plant processes rather than as a preservative.

Across all articles, Issue 067 treats BD 508 as a controllable intervention with defined preparation steps, observable indicators of readiness, repeatable application methods, and measurable agronomic outcomes, while consistently noting constraints, timing sensitivities, and the necessity of integration with broader soil management practices.

Articles 

• How to Make BD 508 (Equisetum arvense) 
• Horsetail Tea (P.  Smith)  
• Fields of Gold Farm Keeps Blight at Bay with Use of BD 508 (Equisetum arvense) (P. Smith, H. Courtney)  
• Sulfur Influence of BD 508 and Climate Control? (P. Smith) 
• Kentucky Farmer Has Many Uses for BD 508 (Equisetum  arvense) (P. Smith)  

Key Topics Covered

• Harvesting and drying protocols for Equisetum arvense
• Fermented versus fresh BD 508 preparation methods
• Observable indicators of fermentation readiness
• Storage stability and continuous fermentation systems
• Application timing relative to crop developmental stages
• Integration of BD 508 with BD 500 and compound preparations
• Fungal disease management under high-rainfall conditions
• Large-scale preparation brewing and application logistics
• Yield and quality observations in grain production
• Limits of BD 508 action in dead plant material

Citation

Applied Biodynamics, Issue 067, Josephine Porter Institute for Applied Biodynamics, Winter 2009–2010.