Preservation of Douglas fir needles

摘要

A solution and process for preserving Douglas Fir needles while preventing shedding thereof from the branch to which they are naturally attached, producing a natural looking product suitable for display purposes. The branches, with attached needles, are immersed in a solution comprising (in amounts per liter of solution): 300-500 ml water 200-300 ml ethyl alcohol 0-75 ml ethylene glycol 50-75 ml propionic acid 0-20 ml glycerin 100-150 ml formalin 50-175 ml propylene glycol 40-75 gms citric acid 1-7 gms magnesium sulphate 15-25 gms cupric sulphate 5-10 gms sodium sulphite 0-10 gms seaweed extract, for a period of up to about two weeks and subsequently air dried.