Hawthorn (Crataegus, pronounced /krəˈtiːɡəs/) abounds. There are more species and varieties than the naturalists care to catalogue, so they often don't bother. Those who want to make their own tinctures should learn Hawthorn, and learn it well.
What does that mean?
If your area is like mine, there are probably Hawthorn trees scattered throughout, from roadway and municipal plantings to wild field Hawthorns and ornamental specimen trees in people's yards. Observe them all and note down their locations. Notice when they flower and when the berries ("haws") are ripe, and now long they hang on the different trees. Notice the size. And notice the taste. Write this all down in your notes and the next year your Hawthorn gathering season will be at least doubled BECAUSE some trees first flower long after the last blossoms fall from other trees. Some bear fruit weeks after others lose theirs, and some trees retain their fruit for a long time after others have lost theirs.
You can harvest Hawthorn both spring and fall (sometimes even early winter). The fall berries were more used in the past, but the springtime bounty may be even more potent, according to some sources. Why not use both?
In the spring the flowers,new leaves, and immature twigs are collected. You can't actually collect just the flowers because what you have in the spring is a new little shoot with some smallish leaves, and some flowers. If you pull the flowers alone off, the petals will scatter, so just take some small scissors or a pocketknife and cut the little shoot off. Or use your fingrs and nails. Be sure to leave plenty of new shoots so there will be berries for the fall.
The scent of the Hawthorn blossom is only somewhat sweet, overpowered by with a disagreeable smell like a dead animal. Last weekend, we picked from a cluster of bushlike trees with extensive side branches. I kept looking for the dead critter, but there wasn't an expired varmint to be seen -- just a lot of pollen wafting about. The smell isn't really bad enough to drive you off, just be aware that these things don't smell like your grandmother's petunias.
Berries: Some are large, some are small, some are pulpy, some have thin skin stretched tightly over the seeds with almost no pulp. Some taste delicious, most taset mealy.
It's advisable to be careful when using herbs harvested from public property or other places that may be sprayed. Personally, I have never seen or heard of spraying hawthorns on any of the public plantings around here, and there are lots of them. But you never know. The best bet is to find a nice, bushy Hawthorn tree on private property and deal with the owner to pick some. Nobody uses these things, though though many are eaten by birds. Also keep in mind that while related to Apples, Haws are much smaller and if there are worms hiding in them, you probably won't be able to find most of them. So your tincture won't quite qualify as vegan. But don't fret about the worms. The vodka will take care of them.
For formulations and benefits, see the writings of Dr. Christopher,Dr. Shulze, and others.