For the best medicine, the buds should be placed in the macerating medium as they are picked. In the winter, it is probably more realistic to just have the oil or vodka ready before you go out to harvest so you can process soon after get back with the buds; otherwise, keep the buds chilled until ready to use; if this will be a long time, consider freezing them.
Poplar buds will leave behind a resin on tools used so have dedicated equipment for processing poplar buds. Do not mash, cut or otherwise mechanically damage the buds before putting them in the macerating oil; ESPECIALLY, do not put the fresh buds in a blender with oil.
Poplar bud oil is simply made by placing one part of fresh poplar buds into three parts appropriate oil: this means for 1 quart of maceration, use three cups of oil and one cup or 1/2 pound of fresh live poplar buds. I use olive oil, extra virgin organic.
Add the cold buds directly to oil at room temperature (circa 70° F) into a glass or stainless steel bowl or pan. Do not put cold buds into hot oil. The warming together promotes gentle cell death and yields a superior medicine.
Stir buds in oil gently with a wooden spoon handle to mix the oil around the buds and to discharge any and all air pockets, which promote decay and spoilage.
Heat the container with the macerate (mixed oil and buds) in a water bath or double-boiler to a constant 115-120° F, and maintain it for at least 72 hours.
Stir the buds with a wooden spoon, gently, in the hot oil four to eight times daily during those first 72 hours (three days) to hasten air and water removal.
For 2-3 weeks (the exact timing is not critical; but doing it the same way each time will tend to yield more consistent product quality and effectiveness) keep the buds and oil macerating together at 90-105° F. Keep covered loosely. Oil extraction speed and efficiency of resinous materials is very temperature dependent; higher temperatures tend to promote better extraction; conversely, I believe even slightly too high temperatures can accelerate molecular fragmentation and degradation, often losing important healing constituents, particularly components of populin and salicin.
After the 3 weeks,, let the oil and buds stand for 48 hours without stirring; then very carefully pour the oil off the buds (decanting) into a clean dry clear glass container; wash this container and dry totally before using; the object is to eliminate water from the final product. Examine the material to look for little water droplets. If any, carefully decant the water in oil and discard. The water-free oil is ready to use, store, blend.
DO NOT PRESS THE BUDS LEFT IN THE MACERATION JAR IN AN ATTEMPT TO CONSERVE OIL You want no squeezing of the buds to prevent release of compounds that can make it rancid sooner. Leaving a little bit of the settled resins in the poplar bud oil seems to yield a more powerful medicine with a longer shelf life,sometimes for years.
Much of the healing action of poplar bud extracts seems to be dependent upon the amount of resins dissolved into them.
POPLAR BUD OIL/SALVES
Poplar bud oil is a wonderful addition to massage oils, especially those used for deep tissuework. It is a superior first aid rapid response topical applied to scalds and burns. Poplar bud oil is antiseptic, speeds healing and lessons scarring. I use a 1:1 mixture of poplar bud oil and fresh St. John’s Wort floral bud oil as our household burn oil. The Hypericum oil is mildly analgesic and stimulates nerve regeneration at burn sites. Michael Moore (1993) recommends using animal fat (butter, lard) for poplar bud burn oil. I suspect a 1:1 mixture of sheep or goose fat can also be used.
Alternative method by Minnesota Herbalist:
I put the buds in a clean, dry mason jar and I added organic sunflower oil. My jar was probably 2/3 full of buds. I screwed on a lid. Then I filled my crockpot with a few inches of hot water and I put the jar into the water bath in the crockpot and covered it. I allowed it to sit in the bath for probably 12-18 hours. Strain then add beeswax to make a solid balm or ointment.
Step 2: Determine how many containers of salve you want to make. Fill the salve container nearly to the top with infused oil and pour it into your stainless steel pan. Don’t fill it completely to the top because the beeswax will add some volume to your final product.
Step 3: Heat your oil gently over low heat. Add a small amount of beeswax. Start conservatively. It is easier to add more beeswax to make your ointment firmer than it is to make an ointment softer. Continue to gently heat the oil until the beeswax is melted. Stir it with your spatula once or twice to make sure it is mixed.
Step 4: Assess for firmness.
Dip a spoon into your pan and pull it up. Beeswax has a high melting point. That means that beeswax cools and hardens quite quickly. When you have used very little beeswax your ointment will remain liquid on the spoon for awhile. When you have used more beeswax and you lift the spoon out you can see near the edges of the puddle of oil the beeswax has already begun to solidify, as you can see in the picture below. If I had used even more beeswax the whole spoonful would rather quickly become solid.
Now carefully pour, spoon or ladle the hot liquid salve into your salve containers. Be careful. It’s hot. Leave your containers on the counter and bring the salve to the container not the container to the salve, because the metal tin will become very, very hot as you pour the salve into it.
POPLAR BUD TINCTURE
Tincture fresh poplar buds in 50-70% aqueous ethanol, 1 part buds to 3 parts alcohol, in closed glass containers at 90-120° F for 72-96 hours, with frequent shaking of the container, and then store the tincture with the buds, decanting off as needed.
CAUTION!! WARNING!! Another complicating factor is that a small, probably less than 1% of the American population seems to have an exaggerated epidermal sensitivity to the poplar bud resin or juice and they develop the early signs of anaphylactic shock; flushed face, labored breathing, hives (often very itchy), swollen face, itchy runny eyes, and some dizziness. Most of these people have general sensitivity to aspirin and aspirin products. Poplar buds contain populin and salicin, phenolic glycosides, both contain salicylates. ONLY use externally. Due to the anti-clotting effects of salicylates, discontinue use of poplar bud extracts (oils, tinctures, teas) 10 days before and after elective surgery and after severe physical trauma.
Following are a few different preparations. Because of it's high resin content (which is not water soluble), cottonwood likes to be prepared in some particular ways.
Infused honey for coughs:
Fill a jar ⅔ full of fresh poplar buds and fill the rest up with warmed honey. It may take a while for the honey to seep in among the buds, so you must be patient. Let that sit for several days, turning it every so often to mix it up. The honey will start to pull out the water and medicinal stuff, and the honey should get visibly thinner. After 3-7 days, you can strain it through a fine mesh strainer into another jar. I like to refrigerate honeys I've made with fresh plant material, since the added water makes them more likely to spoil. I like to taste the honey periodically to see if the strength is enough for me.
Poplar bud honey is best for sore throats and lung congestion. Resinous plants stir up deep phlegm and help get it out of the body. The buds are also antimicrobial, and the honey is antimicrobial and soothing, making it ideal for sore throats. You can eat it by the teaspoonful, or add it to hot water and drink it like tea.
Infused oil for sore joints:
Infused oil is the classic preparation for the resinous buds. I like to make the infused oil by putting the buds and oil in an open jar, and then leaving the crockpot on low for 1-2 days. If you want it quicker, you can put the same jar in a boiling pot of water and let it sit for an hour or two. In general, I don't heat oil directly in the pan, since it can damage the oil and sometimes deep fry the plant material. I have used both olive oil and coconut oil and found them both fantastic.
For sore joints/muscles try adding some essential oils to a small container of the infused oil, like Wintergreen, Basil, Black pepper, Peppermint.
To make into a salve, add beeswax to make the desired thickness. The salve is useful for a few different things, including as an antimicrobial for cuts, and for sore joints (think carpal tunnel). I like to add pine sap, which makes it more warming and good for cold, still, sore joints. You could also add chili, ginger or willow to play up the joint application. Be aware that because of the resin content, poplar oil can be a little irritating to already irritated skin. (this recipe from Minnesota Herbalist).
Gilman, A. et al 1980. The Pharmacological Basis of Therapeutics. Pp 688-698
Grieve, M.1931. Modern Herbal V.1; Pp 311-13
Drum, R. Two Buds One Leaf
Adiantum School of Plant Medicine