Found this plant in the spillway between two ponds at Audubon yesterday. It looks so parsley, or cilantro-esque.
Did you ever think about the word pitch? When I was surfing around to learn more about gummosis, I ran across a phrase that made me wonder about the etymology of pitch.
Whoa… let’s back up… Gummosis. Last winter, I found this Black Cherry that was covered with goo. There was also a little critter stuck in the goo… but that’s a story for another time:
I threw the pictures up on Flickr and got some responses that must have satisfied my curiosity I guess… because I forgot all about it.
Until recently when I saw this goo on a cherry tree… again. Amazingly, I remembered the word “gummosis” and looked it up:
Gummosis is a general, nonspecific condition of stone fruits (peach, nectarine, plum and cherry) in which gum is exuded and deposited on the bark of trees. Gum is produced in response to any type of wound, regardless of whether it is due to insects, mechanical injury or disease. (source)
You can imagine that fruit growers will be on the lookout for this symptom indicating that something is attacking their trees! In the case of Black Cherry, it is the timber folks who are concerned as gummosis can reduce the value of the harvest by as much as 90% (source).
In the case of this most recent discovery of gummosis, it was on the same cherry tree as the Black Knot I wrote about previously. So in this case, it is a fungus causing the tree to produce the pitch…
Oh yeah, pitch! Let’s get back to the word pitch… In one of the sources I read (which I can no longer find, of course) the author suggested that the tree produces the gum in an effort to pitch out the intruder. Pitch to pitch out the intruder… That’s when I started thinking about the word…
It’s a noun… it’s a verb… It is used in lots of totally unrelated ways… Before you check out the following websites all about the word “pitch”, you could play this party game: See who can come up with the most uses of the word!
Some words are just so good that you just have to use them for lots of purposes…
I received more than one comment or email on my Foam in the Creeks post which armed readers with information that could make them nature Smarty Pants when hiking with friends…
Well, here’s another one that may help you when someone asks, “What is that black stuff on the branches of that tree?”
The black, warty galls appear on trees in the Prunus genus. In this case it is Black Cherry (Prunus serotina), but it often affects wild and cultivated prune and plum trees as well. Because all these trees have commercial value, you can find plenty of information about Black Knot (Apiosporina morbosa) and how to control it online!
The Cornell site listed below includes this diagram explaining the “disease cycle” of Black Knot:
While there are fungicidal treatments that can be used, most of the articles first recommend pruning in winter and removal from the site and/or burning of the galls.
Michael Kuo, author of many of the articles at MushroomExpert.com, has a great sense of humor. First, he describes Black Knot as looking like “dried cat poop on a stick.” Each article at the Mushroom Expert site includes information about whether or not the species is edible. Regarding Black Knot, he had this to say:
As far as the edibility of Apiosporina morbosa is concerned, I have four words for you: Look at the picture.
He cracks me up.
- Black Knot Fact Sheet – Cornell University
- Black Knot Fact Sheet – Kearnsey Tree Fruit Research and Education Center, University of West Virginia
- Black Knot – Forest Service, US Dept of Agriculture
- Apiosporina morbosa – Black Knot – The Mushroom Expert
- Causes of Gummosis in Black Cherry – Bradley D. Barnd and Matthe D. Ginzel
I have so often wondered what causes foam in the creeks, but I always forget to look it up. Today, I was going through some old photos and found this one, which I took specifically to remind me to look it up:
Here’s what I found out:
The surface tension of the water is reduced by a surface active agent, also known as a surfactant. This reduced surface tension causes air to be trapped into tiny bubbles at the surface in areas where there is turbulence in the water thus creating foam. The foam starts out white, but will turn brown as particles of sediment get caught in there, too.
The surfactants can be either man-made or natural. Man-made surfactants include chemicals present in many household cleaning products. According to Jeffrey Davis, an aquatic ecologist:
The most widely used synthetic surfactants today are linear alkylbenzenesulfonates (LAS) listed on most products as sodium or ammonium laureth or lauryl sulfate.
If the foam you find in your creek is localized and sweet-smelling, perhaps someone washed their hair or dishes! If the foam has a fishy or more earthy smell, then suspect a natural cause.
The natural surfactant is called DOC (dissolved organic carbon). DOC comes from the decomposition of a wide variety of plant material including algae and aquatic plants, but also the leaves from trees that line the creek. Foam caused by DOC is often widespread, occuring in more than one spot along the creek. You may see more foam after a wind or rain storm as more organic material is washed into the creek and the water is running faster causing more turbulence.
So there you have it! Now you know. You can be such a smarty pants next time you are hiking with friends and they ask about the foam!
Maybe. Probably not. How can you tell? Stick your finger in it (or a stick, if you’re squeamish).
If it immediately “heals” – that is the shiny film closes back up again – it really IS oil. If it doesn’t, it’s a naturally occuring bacteria or other natural source. According to the USGS, these kinds of films “can be found anywhere that ground water, which lacks oxygen and carries iron and manganese, discharges into a stream.” I assume ponds are likely candidates, too. The article goes on to say:
Certain bacteria, the oxidizers, fix oxygen onto iron and manganese. Other bacteria, the reducers, remove the oxygen. In fixing or removing oxygen, some are getting energy and others are performing other life functions. Bacteria have been involved in the iron and manganese cycles for billions of years.
So, don’t worry about your pond being polluted until you stick your finger in it!
Well, I did it. I signed up for the 30-day Sit Spot challenge. It starts today, but it’s not too late. You can sign up, too… And, they are pretty forgiving… If you find out about it late, they just ask that you extend your sitting for a full 30 days.
The idea is that you go to a natural place and sit for 20 minutes each day for 30 days. You write about it, photograph it, sketch it, paint it… Whatever… If you choose to share your experiences with the Wilderness Awareness folks, they may include your contributions in their on-line or print newsletter. (That should not be your motivation to do it, though!)
Read about it here: Sit Spot Challenge