C. lupulina? Spikes mostly pedunculate and drooping or even long pedunculate. All individuals in this spot similar to that. Growing with C. tuckermanii. Extensive stands of both species growing together and mixing stems.

Another weirdly-colored one. Make up your mind damnit! do you want to be red, white, or a hybrid? I've been staring at way too many hybrids, I've lost all sense of what is normal and what is intermediate....

Growing near roadway. The brown insects (14th and 15th photos) observed separately: https://www.inaturalist.org/observations/60135181

Involucre length measurements (in mm) from 4th and 6th photos: 3, 3, 2.5, 2.5, 2.75, 2.5

Leaves and stem surface where array branches grow from the main stem are shown in photos 7-10.

Leaves and stem surface at the place where the lowest array branch grows from the main stem are shown in photos 11-15. These are interpreted to be the “upper stem leaf” as depicted in the “Asteraceae Lab” website (https://uwaterloo.ca/astereae-lab/research/goldenrods/goldenrod-morphology)

Leaves and stem surface at the place half way between the lowest array branch and the ground are shown in photos 16-18. These correspond to the "mid-stem leaf" shown in the depiction referenced above.

Heads in seed shown in 19-20.

Found on dry stony ground on slope. Area is overrun with Common Buckthorn.

The following features are relevant to species identification using Michigan Flora online:

Petals ~ 9 mm long (photo 2);
The summit of the ovary is tomentose (e.g., photo 3);
Leaves rounded to cordate at base, tomenose underneath and some are still somewhat folded.
Leaves have fewer than 20 teeth per side (counts for the leaves in photos 7,8, and 9 are 5, 14, and 18, respectively), and most are finely toothed near the apex.
Photos 7,8 and 9 show the leaf veins anastomosing near the margins (becoming netted so that the main vein doesn’t reach a tooth).

A few additional characters observed 10 days later (May 31st) for the same plant:
This plant has a single stem about 4 cm in diameter at base. No other shoots occurred near the base. The height is about 2 meters. Teeth per cm near the apex of four leaves were 8,5,4, and 5.

The plant was observed again on July 21 - https://www.inaturalist.org/observations/29553729.

This was the spot that made me wonder if there are actually two species of white trillium along this trail. Alternatively, they could all be the same species with just one flower being larger due to microclimate and other site conditions. They were growing on a forested rocky slope above a creek. Looking for input and if there is consensus that these may be two different species I can separate them out into two observations.

The smaller ones appear to be the white form of T. erectum, while the larger one could be T. simile, sweet white trillium. They are said to be very similar in appearance with T. simile being a bit larger and blooming slightly later, which would seem to fit the picture. I've read that they can be distinguished by smell but I didn't know that at the time and since they were growing on the other side of the creek from the trail they wouldn't have been accessible for sniffing anyway.

Variety of sizes, coloration of ovaries. Most plants held flowers above leaves, well-erect. No predominant ovary coloration. Some flowers with blue-green pollen rather than typical cream. Large population, mostly on a hill. Identifying as T. flexipes based on ovary shape (mostly flask-shaped - some variation even in this trait, though) and anther:filament ratio.

284 I suspect an hybrid between A. spicata and A. sanguinea. Arbuste de 3 m de haut à troncs multiples. Écorce grisâtre. Dessus de l'ovaire tomenteux, feuilles 80% ouvertes à l'anthèse, vertes ou à faible teinte rougeâtre. Sépales dressés à étalés à réfléchis en fruits. Fruits gros, 10 mm de diamètre.

Orée d'une forêt ouverte de Fraxinus americana et Acer rubrum. Strate arbustive dominante avec Amelanchier et Rhus typhina et Poaceae au sol. Terre noire.

285 Un hybride entre A. spicata et A. sanguinea? Arbuste de 3 m de haut à troncs multiples. Écorce grisâtre. Dessus de l'ovaire tomenteux, feuilles 80% ouvertes à l'anthèse, vertes ou à faible teinte rougeâtre. Baies rouge foncé, diamètre de 10 mm, longueur de 9 mm in vivo., juteuses, au goût acidulé. Grappes de fruits pas érigées. Sépales ascendants, étalés ou réfléchis en fruits.

Orée d'une forêt ouverte de Fraxinus americana et Acer rubrum. Strate arbustive dominante avec Amelanchier et Rhus typhina et Poaceae au sol. Terre noire.

290 Arbuste de 2,5 m de hauteur avec plusieurs troncs. Racèmes dressés. Feuilles toutes ouvertes à l'anthèse, vertes. Certains pétales émarginés. Orée d'une forêt ouverte de Fraxinus americana et Acer rubrum. Strate arbustive dominante avec Amelanchier et Rhus typhina et Poaceae au sol. Sol sableux et graveleux.

294 Correspond à Viola septentrionalis Greene.

Plantes plus petite dans les zone ensoleillées. Pétales mauve foncé. Poils claviformes au centre des pétales latéraux devenant filiformes à la partie proximale des pétales. Capsules à fond vert mouchetées de violet, couchées au sol. Graines couleur de foin à tachetées de violet, 24-30 par capsule.
Lisière orientée nord d'une forêt secondaire de Populus tremuloides et Prunus virginiana, dans une pelouse. Zone semi-ombragée, avec Poaceae au sol. Terre noire.