- Miscellaneous: syrup
- Crop Production: agroforestry, forest farming, forest/woodlot management
Tapping walnut trees for sap and syrup production produces a highly valued agricultural product while sustainably managing a farmer’s woodland resources. While the potential is there, the sap collection and processing strategies are, to a great degree, unknown. The maple syrup industry is firmly established with well researched collection and sap processing methodologies. Walnut sap and syrup production, primarily from Black Walnut (Juglans nigra), however, requires different approaches. This research and development project builds on and modifies collection and evaporating techniques developed for maple, adapting them to the anatomical and physiological uniqueness of walnut. Working with collaborating farmers that are already experimenting with walnut tapping, studies will be conducted to determine the optimal time to tap walnut trees and the utility of using vacuum collection techniques – common practice in the maple syrup industry – to increase sap flow. Through a sub-award to the Robert C. Byrd Institute of Advanced Manufacturing (RCBI), this project will develop and test a prototype walnut sap collection spout designed for walnut tapping, and test and improve upon a high-efficiency small scale sap evaporator, needed to encourage new farmers to get into the business. Findings from this research and development project will be shared with existing walnut and maple syrup producers as well as small farmers in West Virginia, Pennsylvania, and the Northeast and Central Appalachian region.
Project objectives from proposal:
1) This project seeks to discover the proper time to tap walnut trees to maximize the volume and sweetness of the sap collected. This will allow farmers to increase yield and quality of this specialty crop and thereby increase potential sales.
2) This project seeks to answer the question as to whether vacuum applied to sap collection lines will substantially increase walnut sap flow. Answering this question will allow farmers to develop superior sap collection strategies that improve the reliability of this crop.
3) This project seeks to develop and test a sap collection spout designed specifically for semi-ring porous species such as walnut. It will be designed to reduce sap leakage and increase yield, thus increasing the amount of syrup farmers can process and sell from their walnut tapping operations.
4) This project seeks to adapt “rocket stove” technology to improve the walnut sap evaporation process, creating a small-scale evaporator. Such a model will reduce sap spoilage and achieve greater processing efficiency. This will benefit farmers by minimizing losses and allowing them to start making walnut syrup with a small number of trees and a minimal investment.