Thomas Edison the Botanist

This weekend we visited the Thomas Edison National Historical Park in West Orange, New Jersey. I used to love visiting there as a kid, and I hadn't been there in many years. They recently completed an extensive renovation of the laboratories, so I was anxious to see it again.

Edison built this lab later in his life. It was in this lab that he perfected the phonograph which he had previously invented, and invented the motion picture camera and the alkaline storage battery. He also built factories around the laboratories, to manufacture his various inventions.

Much of the equipment displayed in the Chemistry Laboratory is what Edison was using on his last project, which was incomplete at the time of his death. Edison was asked by his close friend Henry Ford to help find a plant that could be grown in the United States that could provide latex to make rubber. The plant that is commonly used to make natural rubber, the Para Rubber Tree, only grows in tropical climates. Ford needed a stable, inexpensive source of rubber to make tires for his growing automobile business.

Latex is a material produced by about 10% of flowering plant species, and it is believed to serve as a defense against insect infestation. The latex is stored in cells just underneath the outer layer of each part of the plant. If you have ever picked a dandelion and seen the milky white substance "bleeding" from the stem, that is latex. Tiny particles of a natural rubber polymer (polyisoprene) are suspended in this latex.

Edison tested thousands of different species of plants to try to find the ones that made the best quality rubber. He finally settled on a particular species of goldenrod, which he then cultivated to grow taller and with a greater rubber yield. This goldenrod was later named after him, Solidago edisoniana. The photo above is from the National Park Service collection showing Edison (on the left) with his namesake goldenrod.

And here is a piece of machinery in the Chemistry Lab that Edison used to crush the various plant fibers during his experiments and extract their latex.


This is what "crude" goldenrod rubber looks like after the polymer particles have been coagulated and separated out of the latex, which is mostly water.


This sample is dated 1933, which was two years after Edison's death. Edison's wife and employees continued the search for a while, but finally abandoned it when it became clear that synthetic rubber based on petroleum was going to be the material of choice for automobile tires.

Here is a strip of goldenrod rubber, compounded with carbon particles for strength, ready to be formed into a tire.


One of the most intriguing things our tour guide pointed out in the Chemistry Lab was this bottle on one of the shelves.


Here is a closeup of the label.


In case you have trouble reading it, it says "Sanguin Dragonis / Dragons Blood". The tour guide told us they didn't know what "Dragon's Blood" was, and we joked that maybe Edison was a Harry Potter fan. But when I got home I found out pretty quickly on Google that Dragon's Blood is the common name for the red resin produced from several different species of plants.

Maybe Edison had collected this Dragon's Blood to see if he could make rubber from it. Dragon's Blood has been put to various uses over the years, including a varnish and a wood stain. Many of Edison's phonographs came in beautiful wood cases, so this use would make sense as well. Dragon's Blood has also been used as an herbal cure for many ailments including stomach ailments, which Edison suffered from. Maybe someone gave this to him to take as a medicine.

Or maybe Edison just couldn't resist having a bottle of something called Dragon's Blood. He prided himself on having his stockroom filled with every type of material and substance that might possibly be needed for his far flung investigations. Dragon's Blood must surely have been useful for something.

You will be happy to know that I am kind of curious about this, and have emailed the National Park Service to find out. Either the NPS historians do not check Google when doing their research, or maybe our tour guide missed the memo. But I will get to the bottom of this and report back to you!

Gross Stuff in the Hoh Rain Forest

As you can imagine, the Hoh Rain Forest in Washington State is a pretty wet place. This encourages the growth of some pretty nasty looking stuff. Actually, I could have named this post "Fungi of the Hoh Rain Forest", but I couldn't resist throwing in this other gross picture, of a Banana Slug. Check out that nostril!

The field guides say that this slug got its name because it is yellow with black spots, but I think the fact that it is almost as big as a banana was part of it too. The Banana Slug is the second largest slug in the world. Pretty impressive. But what really makes the Banana Slug gross is its sexual habits.

Banana Slugs are hermaphrodites, meaning that each individual has the sexual organs of both a male and a female. They also have very long penises compared to their overall body size. When two animals with long penises get together, things sometimes get out of control, and get wrapped up and stuck where they shouldn't be. The slug's solution is to chew off the stuck penis. Scientists refer to this as "apophallation".

Now that you are completely sick to your stomach, here is something a little more fun - the Banana Slug is the official mascot of UC Santa Cruz. Click here to see him/her in action.

Now, on to the fungi.


As far as I can tell with my limited fungus identification skills, this is an Artist's Conk (Ganoderma applanatum). Here are some older ones, a little higher up on the same tree. As they get old, their bottoms get brown and shriveled, just like humans.


The white, bottom part of these fungi bruise easily, turning brown when you touch them. Some people have made a hobby out of etching pictures on these fungi, hence the name Artist's Conk ("conk" is the term for the fruiting body of a shelf fungus). Here is the website of a prolific creator of "Ganoderma Art".

This revolting mess sort of looks like an Artist's Conk as well, maybe one that is not very healthy.


Here is something a little more colorful. Again showing my limited grasp of mycology, my best guess is that this is a Ling Chih, also known as a Reishi mushroom (Ganoderma lucidum).


The ancient Chinese used these mushrooms to treat many kinds of ailments. It apparently worked so well they called it "the mushroom of immortality". You can buy it in Chinese markets in the form of candy or tea. Modern scientists are starting to study it with promising results, relearning the secrets of the ancients.

Finally, here is some gross junk that I have no idea what it is. But the two Crane Flies in the bottom of the photo seem to like it. (It is never a good sign when flies are attracted to something.) In the event that I have discovered some exotic and unknown organism, let it be known that I have dubbed it "burned marshmallow fungus", because it looks like something someone flung off their marshmallow roasting stick.