Green Group discussion

Toxic plants which are not necessarily invasive - plant them here!

I saw an article about poison ivy, and we don't have this in Ireland so I thought it would be useful to tourists who might need to identify this plant. The standard ivy in Ireland is apparently toxic enough to stop browsing, but not an irritant.

"The problem with poison ivy is that it produces an oil (called urushiol) that will irritate your skin if it stays in contact with your skin for hours. This means:

If you wash your skin thoroughly with soap and water after touching the plant, you’ll wash off the oil (dish soap is recommended)

If you touch the plant or the oil with gloves or another object, that object is now covered in the oil and you need to avoid touching it as well. This could include your shoes or pant legs, for example, or garden tools.

The oil can last a long time, so if you clear out poison ivy from your garden in the fall, then toss your gloves in storage, you can still get a skin rash from touching those gloves the next spring."

https://lifehacker.com/how-to-identif...

The link to Uni of Maryland in that article doesn't bring you to the exact page, so here is the exact page.

https://extension.umd.edu/resource/po...

"Poison Ivy, Rhus (Toxicodendron) radicans, is a common native plant found in woodlands, fields, pastures, farms, and home landscapes. In natural areas, its berries provide nutritious food for migrating birds.
Poison ivy is typically a deciduous woody vine that attaches itself to trees or other objects for support. But it can take on different growth forms depending on its age and growing conditions. When growing in a tree, mature vines become thick and develop dark brown hairy holdfast growths (called adventitious roots). The vines often develop extensive branches that look like the branches of the tree. Poison ivy vines do not harm the trees that are attached to.
In some cases, it can also grow as an upright shrub without support. Shrub forms typically develop when grown in the full sun.
The leaf forms also can vary even on the same plant. They all have the characteristic three leaflets but the leaf margins can be smooth, wavy, lobed, or toothed."

Eleanor Kuhns tells me in her newsletter, that many plants, including toxic ones, used to provide cloth dye. But they needed to be used with a chemical to fix the dye onto the cloth, and sometimes that was toxic too.



"Napoleon - and dying for Green
Green is just about the most common color in nature so finding a great green dye should be easy, right? Well, despite the fact that green leaves and plants are all around us, a beautiful green is hard to find.

Many plants yield a light celery green or yellow green with the proper mordant. (A mordant makes the dye stick to the fabric. Otherwise the dye would wash right out.) Lily of the Valley and hydrangea both give a celery green dye. But Lily of the valley is highly poisonous; roots, leaves and flowers. Queen Anne's lace gives a pale green and foxglove an apple green. The colors are not the vibrant shades we expect.
In Peru the women use leaves that they gather in the forest from the chilla (spelling? Sorry, I only heard this and it was said by someone with a heavy Spanish accent.) plant. When mordanted with copper carbonate it produces a sage green, sometimes light and sometimes dark.

A word about mordants. Iron, copper, alum, lye, tin, mercury urine; just about every substance imaginable, including urine, has been used as a mordant. In the middle ages the men who dyed hats used mercury, a very poisonous heavy metal. The Mad Hatter from "Alice in Wonderland" wasn't just a creation of Carroll's imagination.

The other problem with natural dyes is consistency. It is difficult to use plants and achieve the same result time after time. Dyers quickly learned to cultivate dye plants as an aid to controlling the brightness of the colors. Even then, dye plants dyed in a wide range of hues. Madder, which dyed the British red coats red, dyes bright red unless it dyes pink. (When I grew madder and tried to dye with it, pink is what I ended up with.) It is very difficult to achieve the same color over and over.

Which brings us to green. A bright emerald green was not developed until 1778. It was created by a Swedish chemist named Karl Scheele and contained arsenic. Green was a popular color for wallpaper then. (George Washington himself took time from his busy political life to plan two green rooms at Mount Vernon.) Many many people fell ill. The cause was frequently misdiagnosed since the symptoms were general and came on gradually. One theory is that arsenic may have been made into a gas by the mold living in the wallpaper paste in damp rooms. (Mmm, this sounds safe.) This dye was even used for candy for children.

In 1875 the 'Lancet', a British medical journal, spearheaded a campaign to abolish the arsenic greens. By then the aniline dyes were being created from coal tars. These dyes created vibrant colors that were much more colorfast and safer.

So what does this have to do with Napoleon? When imprisoned on the island of Elba, he spent much of his time in a room with the fashionable green wallpaper. When his hair was tested in modern times, it revealed a high level of arsenic. At first, it was theorized he'd been poisoned. A more recent competing theory suggested he'd been poisoned all right, by the arsenic in his wallpaper.

Natural is not always safer and while I wouldn't use cooking utensils for my dyestuffs at least I am assured that none of them contain arsenic!"

The toxin in many plants is cyanide. These are just some of the books using plant cyanide as a plot point.