Cut the scrubbed, trimmed quackgrass roots into roughly one inch long sections. In a large stockpot, boil the roots gently with 4 points of water and 1 ounce of citric acid until they are tender.
Meanwhile, chop the raisins and place them in your 1 gallon fermenting crock or pail.
Strain the quackgrass root liquid and pour over the raisins. Cool completely.
Add the nutrient tablet and wine yeast. Stir well.
Cover and allow to ferment for 5 days, stirring each day.
Heat 1 1/2 pints of water, add 3 pounds of sugar. Mix until all sugar is dissolved. Add citric acid. Stir until dissolved. Let cool.
Strain quackgrass root/raisin ferment. Mix quackgrass water and sugar water. Pour mixture into 1 gallon fermentation vessel, fit with airlock.
Allow to ferment 6 months, racking at 3 months if desired. Bottle and ferment for at least a year total.
This made about 1/2 gallon of wine (2 bottles). The flavor reminds me of plum wine – sweet, a little earthy, but with some nice fruity notes. You could easily double it, if you had the patience to clean up enough roots.