Sunday, August 30, 2020

Plant Story--St. John's Wort, Klamath Weed, Hypericum perforatum

Today, you mostly hear of St. John's wort (Hypericum perforatum, St. Johns wort family, Hypericaceae) as a medicinal plant. It has been shown to be effective treating depression, anxiety, and sleep disorders and is widely used for those. But when I studied ecology in graduate school in the 1970s, under its American name, Klamath weed, it was the weed in a major weed-control story. So here are both tales.

Hypericum St. John's wort
St. John's wort, Klamath weed, Hypericum perforatum

Sunday, August 23, 2020

Messy Forests


Rocky Mountain National Park

Walking in Rocky Mountain National Park, there are many places where fallen trees lie. It looks messy. 

                        Fallen trees, Rocky Mountain National Park

The visitor might think: they should clean that up, but perhaps they don't have the budget, or the spot is inaccessible. 

It is more complex than that. Leaving fallen trees lie may be the best use for them. 

Sunday, August 16, 2020

Plant Confusions--More than Three Coneflowers

coneflower, Rudbeckia
coneflower 

If you are confused when someone points out a coneflower and it is not what you expected, you are not alone. I count forty different plant species in five genera that are called coneflower. Some you will probably never encounter, but three genera, Echinacea, Rudbeckia, and Ratibida, are relatively common and sold as garden flowers. I'll start with those.

Sunday, August 9, 2020

Plant Story--Cinquefoils, Potentilla

"If any man will ask any thing of a king or prince, [cinquefoil] giveth abundance of eloquence, if he have it with him, and he shall obtain that which he desires," wrote Albertus Magnus in the 13th century. Well, not really. Albertus Magnus (d. 1280, biography) was a real person, a famous medieval German scholar, but The Book of Secrets of Albertus Magnus was an anonymous work of folklore and superstition that appeared in the 16th century. But, clearly, cinquefoil was considered a powerful plant.


Cinquefoils were medicinal and magical plants in Europe. They are a group of plants in the rose family (Rosaceae) with pretty five-petal flowers, usually yellow, and distinctive leaves with five lobes like a hand. The common name, cinquefoil, means five-leaf in French. Old English names included five-finger grass (grass meaning "plant" in this context), but some species had distinctive names, for example silverweed and tormentil.

Sunday, August 2, 2020

Plant Story--Shrubby Cinquefoil

shrubby cinquefoil Dasiphora fruticosa
shrubby cinquefoil, Dasiphora fruiticosa

Cinquefoils are cute little flowers, usually yellow, in the rose family, Rosaceae. Traditionally they were in the genus Potentilla. Shrubby cinquefoil of the northern and western North America (see USDA map link) was for many years called Potentilla fruticosa. It is easily distinguished from the 68 native and 8 introduced species of Potentilla in North America because it is the only woody shrub, not a non-woody herb. Then, some years ago, DNA and other evidence indicated that shrubby cinquefoil and the other cinquefoils that are shrubs (11, all from Eurasia) were pretty different from other cinquefoils, so they were reclassified into another genus.