Nature Blog Network

Friday, October 31, 2014

Butt-rot Fungus

Weeping oak bracket
We found this large fungus on the base of a 14" tree stump.  Mark Bower identified it as Inonotus dryadeus, 'the weeping oak bracket.'  This is an inedible fungus (I suspect none of you were even tempted) which probably has the least-appealing common names in the fungal kingdom: 'weeping oak bracket,' 'warted oak polypore,' 'weeping polypore,' 'weeping conk'! Adding insult to injury, it is classified as one of the 'butt-rotting' fungi.


The term 'butt-rot' doesn't refer to a side-effect of tasting it but to its place in the woods.  It is found on or around the base (butt) of a tree, or in the case above, a tree stump.  It is found on oaks here as well as fir trees in the western states.  Michael Kuo describes it well.
"Inonotus dryadeus has a lumpy, irregular cap with a finely velvety, dull yellow surface and a margin that exudes droplets of amber liquid when fresh and young. It has a buff pore surface that bruises and ages brown, composed of very tiny pores."
 

Inonotus dryadeus is primarily a parasitic fungus although it can remain as a saprophyte after the tree is dead.  The food web depends on natural recycling and saprophytic fungi such as this are important decomposers of trees.  Saprophytes break down protein to amino acids, fat into fatty acids and glycerol, and carbohydrates into absorbable simple sugars.  When saprophytic fungi absorbs these, it becomes a food source for insects, starting a long trip up the food chain.
Weeping oak bracket closeup
Viewed really close up, a weeping oak bracket fungus is even more interesting.  I am frequently surprised how something plain or even ugly from a distance can have a strange beauty closeup.  The picture above, posted several days ago, shows the glistening liquid drops shining in the sun, beautiful if not appetizing.


There are many types of saprophytic fungi.  Some do primary damage to trees, others occur on wounded or damaged trees, or on dead trunks and roots.  The first sign of the root and butt rot fungus may be a dying tree or a blow down unearthing dead roots.  Our specimen above was on the stump of a tree that died a few years before, possibly because of the fungus.

Honey mushrooms between the trees
We found a lot of honey mushrooms, Armillaria mellea, growing along the ridge.  Some were at the base of trees but many were several feet away, probably growing on the roots which are shallow in the rocky glade-like soil.   The density of this population is probably not a good sign as the infestation can kill a weakened or even a healthy tree.

Honey mushrooms
I completed a Forestkeepers tree survey in the area and didn't show any signs branch dieback or discolored foliage.  A. mellea is a versatile species which can continue to grow on dead wood unlike many other species.  There are several large (14-19") long-dead oaks in the area and I am hoping it is just feeding on the remains of their dead roots.

A good source of information about root and butt rot fungi in general is found here.

Wednesday, October 29, 2014

Red Flat Bark Beetle

 

The leaves are slowly trading their chlorophyll for fall colors and the mornings in the valley are creeping toward freezing.  Thus begins firewood season, the time to start cleaning up downed logs and branches that have piled up in the grass and thickets along the road.  It is also when I start finding more creatures that live in the frass and fungi under the bark.

The bark peeled easily off a long dead log, revealing the many tracks of bark beetle larvae and other denizens of the dark under bark world.  Centipedes scurry away before I can photograph them and tiny jumping spiders tease me, pausing for just long enough to start to focus on them before bounding away.

Eyes bulge out the side of its head - REK
Another chunk of bark yields a treasure.  Bright red, it lays still in a track of frass.  It is striking in this world of dark brown, seemingly unaware that it stands out in the light of day.  This is a red flat bark beetle, Cucujus clavipes.

It is the largest of the flat bark beetles but measures less than a half inch long.  Its flattened body is an advantage when it comes to traveling the tunnels under the bark created by other larval prey.  It is bright red including prominent femurs, with black antennae and legs.  Its eyes bulge out the sides of its head.

Note red femurs with black legs - REK
For a beetle said to be common, there is surprisingly little known about it.  It can be found under the bark of recently felled deciduous trees.  In this hidden world, its eats in private, presumably munching other arthropods or worms.


The larva is also flatbacked.  When I peeled back the bark I would get a fleeting glimpse of flat brown insects looking like legless centipedes.  They had legs in front and although they were not fast, they disappeared into tunnels before I could focus on them.  Finally I was only able to get the slightly blurred picture on the right of one escaping. Fortunately I have Tom Murray's picture to fall back on.
tom murray
While little is known about their under bark life, their winter survival in Alaska is rather famous.  A lot of research has been done on their ability to tolerate supercooling in harsh arctic environments.  C. clavipes puniceus is reported to be able to survive temperatures at -70F by producing glycerol and sorbitol antifreeze chemicals.  A later study showed that some individual larva could tolerate even greater cooling by decreasing its water content.


Peeling off some dead bark can expose intriguing patterns of insect larval tunnels.  There is a lot more you can learn in Charley Eiseman's book Tracks and Signs of Insects and his Bugtracks blog.

Fall is a good time to roll over rotting logs to look for signs of life in the underworld.  Just remember to roll them back in place.  Leaving it exposed is the equivalent of running a bulldozer through their neighborhood.

Animal, vegetable, mineral or other?  You decide.

Sunday, October 26, 2014

Venomous Caterpillars




Puss caterpillar - MDC
An article in the Springfield News-Leader had the interesting title Venomous Caterpillars Rare in Missouri, but....  It concerned the puss caterpillar, said to be named because it resembles a soft cat.  It is the larva of the southern flannel moth, a species uncommonly found in southeastern Missouri but having its 15 minutes of fame due to an increase in the number of human encounters this year.  This little ball of fuzz has been called the "most venomous caterpillar in the US."

First let me be clear.  You are extremely unlikely to run into one in the Ozarks.  The article was prompted by questions from residents from the Bootheel.  Although it looks like an aerial view of Donald Trump's head, beneath the soft fuzzy exterior lie toxic spines that stick to your skin and cause pain greater than a bee sting, frequently radiating up an arm and lasting hours.  If you're curious read more in this National Geographic link.

Saddleback Caterpillar - Acharia stimulea
Saddleback caterpillar - Nikole Loomis
We do encounter less toxic stinging caterpillars in Missouri and a few pictures of what not to touch might be helpful.  The saddleback caterpillar above (Acharia stimulea) is quite colorful and distinctive example.  A good rule of thumb (or finger, hand, arm etc.) is avoid touching caterpillars that are hairy unless you know the species.  An obvious example of harmless is everyone's favorite weather forecaster, the wooly bear.

Wooly bear - Wikimedia, IronChris

Most of the stinging caterpillars look threatening.  If it looks like it would hurt, you are best to believe it.  Common examples in Ozark species include the stinging rose caterpillar (Parasa indetermina), buck moth caterpillar (Hemileuca maia), and the Io moth caterpillar (Automeris io).

VA catepillar - Automeris io
Io moth caterpillar - Tim Lethbridge
Is this some form of Buck Moth? - Hemileuca maia
Buck moth caterpillar - Donna

Caterpillar - Parasa indetermina
Stinging rose caterpillar - Derek Hauffe  


Probably the Missouri caterpillar voted "Least Likely to Touch" would be the hag moth caterpillar (Phobetron pithecium), also called the monkey slug.  The common response would be somewhere between "what kind of creature is that?" and "Yuck!"  Good protection, as it too has stinging hairs.

Hag Moth Caterpillar - Phobetron pithecium
Hag moth caterpillar - Jo Ann Poe-McGavin
If you do come in painful contact with one of these, the first aid consists of duct tape or scotch tapeAccording to MDC Forest Entomologist Rob Lawrence:
"Stings from some venomous caterpillars can be quite painful, but not deadly, according to Lawrence. Stings can be covered in scotch tape to remove any remaining spines, and then washed thoroughly with soap and water to clean the wound. Applying ice or baking soda may help reduce the pain. Stings should be observed to ensure allergic reactions don't occur."
Special thanks to all those who post their photographs to Bugguide,net and other sources using a Creative Commons License or otherwise permitting their use for educational purposes.  Consider this when posting your photographs.



Thursday, October 23, 2014

Fall is Falling

Fall is here at last, even if it seems a little late in arriving.  We have our annual neighborhood music party on the third Saturday of October which is usually at the height of leaf change.  Yesterday the valley was green with patches of gold and orange from the upper half of sugar maples while the oaks remain green.


Others have noticed that the peak season is later this year.  The website smokymountains.com has a map of the United States which shows the progression of leaf change across the country.  They are calling for the peak change for our area on November 8th.  If this occurs we should be in for a long slow progression of beautiful trees.

Jeff Cantrell offers a philosophical look at "America's Top Models", the trees of fall, in his Chert Glades Master Naturalist Nature Blog posting.  It is just one more call for naturalists to get out of the house and into the woods.

At Bull Mills we are still seeing the occasional monarch pausing on its journey south.  Caterpillars are reaching their last instars and heading to the ground to pupate for the winter.  It is the time for the wooly bear forecast.
Wooly bear - REK

The weather bureau aside, the long term forecast for winter is still quite mixed.   Folklore has it that the wider the brown center stripe is on wooly bears (that is Pyrrharctia_isabella caterpillars) the milder the winter.  If that is true the one above suggests you won't need your snow tires this year.  This will come as a shock to a few, but studies have not shown the wooly bear to be very accurate.  The color distribution has more to do with the past year's weather, affected by the length of the growing season.  Even the thickness of the coat is not accurate.  Regardless of their appearance, the caterpillars live through the winter with their antifreeze, and they have been shown to survive while frozen in an ice cube.  (See this NOAA site.)


On the other hand, if you go by the persimmon seeds, it is a toss up.  My friends report mixes of  knives, forks and spoons that sound like a trip through a kitchen drawer with no agreement between them.  I guess we will just have to wait and see.

Wednesday, October 22, 2014

White Micrathena

Micrathena micrata - REK
M. gracilis - Wikimedia
Driving through the woods we encountered the usual spiny orb weaver spiders (Micrathena gracilis) we wrote about in July.  One however looked a lot smaller and turned out to be a white micrathena - Micrathena micrata.  Its abdomen had a different shape and it has only two black spines, unlike the six spines of M. gracilis seen on the right.

It was originally described by Nicholas Marcellus Hentz (1797-1856) in 1850.  He was a French-American scholar, a professor of modern languages, and an arachnophile.  For you arachnophobes, the 'phile' means someone who 'loves, likes or is attracted to' instead of fearing.  In his spare time, Hentz described 124 species of spiders, species that were overlooked by other new world observers at the time who were studying more charismatic arthropods such as beetles and lepidoptera.

Incredible as it sounds today, all this study, writing and classification, eventually published by others, was a hobby, no pay and little recognition.  Most of the science at that time was what we now call "citizen science."  While we how have trained scientists to collect, codify and make sense of what is published, much of this came originally from passionate amateurs.


Without wading into the morass of the formal naming and renaming of species, M. micrata is Latin for 'wearing a turban.Hentz wrote that "The abdomen viewed from above resembles a bishop's mitre."  As you can see above, he made a very good point.

The competitive exclusion principle states that "No two species can occupy the same niche in the same environment for a long time."  How do these two species seem to exist together?  While M. micrata is more common to the north, their range overlaps in southern Missouri.

They coexist side by side in some geographical areas and their niche is not identical.  M. micrata is only a quarter inch long, half the size of M. gracilis.  Its web is lower and more dense that M. gracilis, aimed at finding smaller prey flying low above the lower forest floor.



The next time I walk into a face full of white micrathena's web, I will try to remember that it was just looking for tiny flying creatures and I am just its 'bycatch.'

You can download The Spiders of the United States (1875) by Edward Burgess for free at this site.  It is an interesting look at the original descriptions of spiders in the mid-eighteenth century.

Monday, October 20, 2014

Goldenrod Galls

New research has shown that bison feeding on the prairie increases the diversity of species even as it reduces the biomass of the grasses and forbs.  As Dr. Matthew Moran explained to Entomology Today, arthropod abundance and diversity was greater in bison grazed prairie than in control fields.
"Even though the bison reduced the amount of grass by 50% or more, the overall abundance and diversity of arthropod herbivores and carnivores increased significantly, especially among sap-feeders. In addition, Dr. Moran suggests that this may also be beneficial to birds and and other animals that eat insects."
Goldenrod stem gall - REK
We recently explored the Rotary Club Nature Park in Mountain View with our friends Jack and Marty Toll.  Marty showed their beautiful Butterfly Garden, a wooly field of native nectar and host plants sure to warm the heart of any leipdoptera.  Their goldenrod scattered through the field also demonstrated another way that species diversity is maintained by providing a home for insects in the form of galls. 

Stem gall with larva - REK
Larva closeup - REK











The round goldenrod stem gall above contains the maggot larva of Eurosta solidaginis .  These in turn can feed the predaceous beetle larva of Mordellistena (below).  According to Bugguide, "Apparently smaller galls are parasitized more often than larger ones; but the largest ones are eaten more often by chickadees and wood peckers."  Once again this illustrates the importance of goldenrod in the food web.

Beetle larva is gall - Beatriz Moisset
There are many species of goldenrod including the genera Solidago and Euthamia.  Goldenrods in general support a wide range of gall-forming insects.  The plants survive the stress while contributing to insect diversity and the food web.  There are over 50 species of gall forming insects, two thirds of which are midges in the family Cecidomyiidae.  The genus Rhopalomyia alone has 16 species which produce galls in either the bud, leaf, stem, rhizome, or flower-head of their specific goldenrod host species.
Flower head or rosette gall - REK
There are other species that produce a wide variety of goldenrod galls.  While the round or elliptical galls on the stem are easily recognizable, the flower head, bunch or rosette galls are stranger.  They produce a mass of leaves in a cluster, somewhat similar to the mass of twigs of a witch's broom growth on a hackberry.
"In addition to the gall makers we should consider all the parasitoids, predators and inquilines. The total numbers must be quite substantial. In some cases more than fifty percent of galls are parasitized; furthermore, it seems that for each species of gall maker there are at least three or more different species of parasitoids, inquilines, etc."  (Bugguide.net)
"Inquiline" refers to an organism that lives commensally in the nest or structure of another organism, usually for the purpose of sharing food or resources. This could be a small spider on a larger spider's web or caterpillars living in ant nests while sharing their honeydew, in the common parlance, a type of "friends with benefits."  Many inquiline species live in the structures produced by gall making insects.

A wide variety of moths feed on goldenrod, and wasps, spiders, birds and other predators use their larva.  A patch of goldenrod can contain a whole microcosm of life.  An incredible food web awaits the patient naturalist with curiosity and a hand lens or a good camera.  We will look at some goldenrod inhabitants and their predators in a followup blog.

Many of the gall forming species and their predators are found on the Bugguide.net site.

Friday, October 17, 2014

Pelecinid Wasp

Pelecinus polyturator female
Sometimes a picture grabs me.  This one was sent to me by a friend of a friend and was taken when the creature had landed on the rim of his truck bed.  (My truck wasn't that clean when I bought it!)  She looks like one mean wasp, a creature that could get its stinger into your gall bladder!

Fortunately for us, she doesn't have a stinger, just an extended method of "laying" an egg.  This is a female pelecinid wasp.  They have elongated articulated abdominal segments (metasoma) with an ovipositor on the end.   You will notice that the "ankle" is thicker than the leg segment above or below it.  Also the antennae are very long, all typical of a female Pelecinus polyturator.

June beetle grub - REK
The extended abdominal segments are not just for show.  The female P. polyturator has to deposit her egg on a June beetle grub.  Her larva is parasitic and will feed on the grub as it develops.  The grubs burrow as deep as eight inches into the ground, so the female needs the long extension to reach them. 


P. polyturator male - Larry de March
Only the females are commonly seen.  The males are half their size, with the same long antennae and leg anatomy but with a shorter non-articulated abdomen.  Females don't need the males on a daily basis as they are parthenogenic, meaning they do not need to mate to produce fertile eggs.

The wicked looking abdomen probably serves to protect the wasp from curious humans but even if she used it in defense it wouldn't penetrate your skin.  It is more like a "Baby on Board" decal, so don't swat, just take pictures.

The June beetle grub is fascinating on its own, moving on its back by the use of hairs, its relatively useless legs flailing in the air.  See this previous blog.

Thanks to Brian Hoover for the picture that started this topic and to Larry de March for the use of his photograph of the rarely seen male.