Posts Tagged 'galls'

The Gall

A species of oak gall wasp I haven’t seen in Brooklyn: Spongy Oak Apple Gall Wasp (Amphibolips confluenta). This one, along with several others, was found in Dutchess Co. recently.
Here’s another I cut in half:
This tiny wasp lays its eggs on at least eight species of oak.

The IPCC’s latest report Climate Change 2022: Impacts, Adaptation and Vulnerability, is very, very, very bad. I suppose we can chalk it up to irony that this “atlas of human suffering” comes out in the midst of Putin’s invasion of Ukraine. The bloody connections between autocracy and petroleum are well established: Putin’s Russia is a petrostate, like Saudi Arabia, a regime of corruption and repression led by an assassin.

Meanwhile, Charles Koch, one of the major funders of the assault on American democracy, that Republican project that has worked hand-in-glove with Putin, is also a big supporter of a case now before the Federalist Society’s SCOTUS majority challenging the EPA’s ability to regulate greenhouse gasses. We concentrate on the hidebound social politics of the Republican-dominated Supreme Court, but it is also of course profoundly reactionary across the board.

As a reminder: Charles Koch is a scion of oil and gas money. His father Fred was also a founder of the John Birch Society. Another oil man, Lyman Stewart, is largely responsible for funding the birth of Protestant fundamentalism in the US a century ago. These are examples of what was once called the “lunatic fringe,” but they have become the foundational base of the modern Republican Party. A party that condemned two of its members for investigating the Trumputsch in Washington, but won’t sanction three of its members for supporting the Hitler-friendly America First PAC meeting this past weekend.

Gall Week

We’re in the midst of a iNaturalist project called Gall Week 2021. Some 116 people have found 544 species of galls (as of Wednesday p.m.). I”ve contributed 31 species, including these Andricus weldi on white oak, and the following:
Andricus quercusflocci on white oak. The little one to the lower right seems to be undescribed.
Woolly Oak Gall (Callirhytis lanata) on scarlet oak.
Two on a pin oak leaf:
These are Furry Oak Leaf Gall Wasp (Callirhytis furva).
And this one is Zopheroteras guttatum.
Another two-fer, on scarlet oak. Those are old Macrodiplosis majalis on the right (these are induced by gall midges, unlike the others here, which are induced by gall wasps).
The others on that scarlet oak leaf are Kokkocynips rileyi.
These are more are found within a mile and a half from my home in Brooklyn, NY. Off the top of my head, I can think of four species found on swamp white oaks planted in our sidewalks. Check out the Gallformers site for help on identification.

Got Galls?

Phylloteras poculum, no common name, is a tiny gall wasp. They lay their eggs on a white oak leaf, and the tree responds by building this structure, which envelops the egg. The larva inside is protected from the elements, including, to a certain extent, predators, and has plant material to eat in there.

Every species of gall wasps, and there are hundreds, induces a unique gall structure on their host oaks.
Shriveled up ones on a fallen leaf.

Charismatic Galls

Hedgehog Gall Wasps (Acraspis erinacei) on white oak.


Here’s another gall for your collection:
Cypress Twig Gall Midge (Taxodiomyia cupressiananassa).
Affects Bald and Pond Cypresses. I like how they almost kinda look like the cones.

Yesterday, Trump mafia family members Ivanka and Jared tweeted that they were sending in their mail-in ballots, just hours after Trump railed again against mail-in balloting once again. He’s been lying about this for months to undermine the validity of mail-in ballots, while his own advertisements have been filled with claims he was using a mail-in ballot, going so far as show a close-up of his signature on the alleged mail-in ballot. (He seems to have voted in person in Florida this past weekend.)

Wisconsin’s Koch-funded denial of votes received after Election Day has been cleared by the Supreme Court, 5-3. (Amy Covid Coathanger Barrett would have made that 6-3. She becomes the third member of the radically reactionary SCOTUS supermajority who worked on Bush’s 2000 judicial coup.) In a sinister footnote to this Wisconsin decision, Injustice Kavanaugh has essentially announced his intention to not let votes be counted if it will help his master. The USPS is still run by a Trump loyalist (and private mail delivery profiteer), with all evidence suggesting that ballots are being delayed in the mail.

It now behooves us to vote in person if at all possible. I did it yesterday.

Fall Galls

You may be-galled out, but I’m certainly not. All of the above were gleaned from under a great white oak, the mother (?) of galls, on October 10. Five species of gall wasps are represented here.
Pea Gall (Acraspis pezomachoides).
Philonix nigra.
Round Bullet Gall Wasp (Disholcaspis quercusglobulus).
Andricus wendi.
Clustered Midrib Gall Wasp (Andricus dimorphus).
In this latter case, a leaf with most of the cluster still attached had also fallen.

Notes on Galls

Galls are highly specialized plant tissues whose development is induced by another organism.”

The relationship is essentially parasitic, says Britain’s Plant Galls: A Photographic Guide, but “few gall-causers seem to cause more than localised, short-term damage to their host plants.” This book continues: “Plant galls can be caused or induced by a very wide variety of organisms, including bacteria, nematodes or eelworms, and even other plants, but most of our galls are caused by insects, mites, or fungi. Although we do not know exactly how the galls are initiated, it seems clear that most gall-causers interfere with the development of the host plants’ cells, either chemically or mechanically, and cause them to develop into gall tissue.”

This Britain’s Plant Galls is good: “Many gall wasps induce no galls of their own but lay their eggs in the galls of other species. Their grubs benefit from the food and shelter found there and, although they do not harm the gall-causers directly, by competing for the food supply they can starve them to death. These ‘lodgers’ are known as inquilines. Quite a few flies have similar life styles. Parasitic species, which include many, often brightly chalcids, actually feed on and kill the rightful occupants of the galls. The female parasite tends to have a long ovipositor with which she penetrates the galls to lays her eggs in or on the host grubs. Strictly speaking, these insects should be called parasitoids because typical parasites do not kill their hosts. Parasitoids also attack the inquilines, and a large gall, such as an oak apple, can house a very large insect community, consisting of dozens of individuals of several different species.”
Here’s a good description of gall-makers in an article on the co-evolution of plants and gall-forcing herbivores like the Cynipid wasps:

“Gallers are specialized herbivores that induce the development of, and feed on, modified host plant tissues that, relative to surrounding nongall tissues, have elevated nutritive value but contain very low concentrations of toxic secondary plant metabolites.” ~ “Extreme Host Plant Conservatism during at Least 20 Million Years of Host Plant Pursuit by Oak Gallwasps” by Stone, et al. Evolution Vol. 63, No. 4 (Apr., 2009), pp. 854-869.

They somehow side-step the plant’s defenses and get better than average food out of the deal. Nice work if you can get it!

From the same article: there are about 1000 oak gall wasp species. They’re associated with oaks (Quercus) and other Fagaceae. Almost all alternate sexual and asexual generations, and each of these generations has a distinct gall — sometimes on other oak species.
You’re unlikely to ever see any of these small wasps unless you raise them yourself, so we know them by their work, the galls themselves.
I’ve logged 26 species of Cynipidae gallwasps in iNaturalist. Twenty-four of these have been in Brooklyn, all in Green-Wood Cemetery but one. (Years ago I also found an oak apple on a Cobble Hill sidewalk, but don’t seem to have preserved any memorial of it. Got my eye out for them now.)

Cecidologist: one who studies galls.

All the gall posts here at B & B.

Back To The Galls

Andricus quercusstrobilanus on swamp white oak (Quercus bicolor). There’s no common name for this gall-forcing wasp species.
Note the gap here, and the hollows within.
The individual galls brown and shrivel up as they grow. Then they fall to the ground. (I don’t think this is standard for gall wasps in general).
Since this tree had two other similar clusters, I thought it was ok to take a living sample, i.e., no exit holes for the wasp. (Many Cynipid wasps emerge in the fall as a flightless generation. Looks like this species overwinters, however.)
I cut one open.
Behold, the larva!
With something growing on it! So a gall is good protection against the vicissitudes, but it’s not foolproof. There are parasitic inquiline wasps that prey on gall wasps.
There are also parasitic wasps that prey on the parasitic wasps of gall wasps.

Even More Galls!

Andricus incertus on swamp white oak (Q. bicolor) acorn. (All the below are on various swamp white oaks as well.)
A cluster of Oak Rough Bulletgall Wasp galls (Disholcaspis quercusmamma). Note the ants and bee.
Bald-faced Hornet and Asian Lady Beetle, too. In fact, I found several with lady beetles on them. Are the galls extruding something sweet to eat?
This one is out of the ordinary, if any of these extraordinary gall structures can be called ordinary. Andricus quercusstrobilanus. (You’ll be noticing a number of these things don’t have common names.)
Oak Rosette Gall Wasp (Andricus quercusfrondosus).
And fresh versions of the same.

More Galls

This is Andricus capillatus, a Cynipidae gall wasp like all these specimens today, on a white oak.
Round Bullet Gall (Disholcaspis quercusglobulus), on the same white oak. This magnificent specimen of a tree is on a slope, with one branch sweeping down below eye-level, which is essential when searching for these things.
Here’s another Round Bullet Gall, from a previous year (and again, the same white oak). These are quite woody and persistent. Notice the exit hole. The wasp cut its way out.
Inside is the cocoon.
The empty cocoon. The wasp had to get out of here before cutting through the gall structure.
Millimeter scale.
Acraspis pezomachoides, same tree. Pea-sized.

Remember, the tree itself forms these galls in response to the irritation of the wasp. What fascinates me is how each species of wasp forces a characteristically differently-shaped gall.


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