Some Galls and Flux along the Cosumnes River Trail, 10-09-20

I got up around 6:30 this morning and was off to the Cosumnes River Preserve by about 7:15. It was partly cloudy, and I was actually hoping there would be some fog nearer to the preserve – but, no.

I went around Bruceville and Desmond Roads before going into the preserve itself. Again, there were cattle in the fields – including a lot of cute calves.  I got to watch one as he was nursing, and drooling out stands of spit and milk. Hah!

Charolais calf, Bos Taurus var. Charolais

There were different kinds of sparrows in among the weeds and overgrowth, and small flocks of Western Meadowlarks, blackbirds, and Brown-Headed Cowbirds. Along Desmond Road, in the distant fields, I could see mixed flocks of blackbirds, Canada Geese, Great and Snowy Egrets and Sandhill Cranes. I noticed that one of the cranes was sporting some leg bands. I couldn’t see if there were numbers on any of them, but I reported the sighting to Saving the Cranes anyway .

Sandhill cranes among Canada Geese, egrets and blackbirds.

I had just been to the preserve on Sunday of this week, but today, I wanted to take the River Walk Trail behind the nature center, heading toward the river. I wasn’t able to do the whole round-trip three miles, but still, I thought I did pretty well. There isn’t any water, really, in the fields along the trail, so not a lot of waterfowl to see there.

Listen to the sound of the Red-Winged Blackbirds along the river!

I was astonished to find some of the branches on the smaller Valley oaks just covered with Flat-Top Honeydew galls. I usually see those galls singly or in small clusters, but on these trees, there were dozens and dozens of the gall all crammed in against one another.  I wondered if there was some kind of correlation between those smaller trees and the floods that the preserve is subjected to every year. The small trees would be under water for a month or more… Maybe that makes them “softer” or more easy for the wasps to lay their eggs into the bark?  I don’t know; just wondering.

Galls of the Flat-Topped Honeydew Gall Wasp, Disholcaspis eldoradensis

I also found several of the oaks “weeping” with either some kind of flux or Sudden Oak Death pathogen. One of the trees had the classic flux symptoms: breaks in the bark near the base of the tree, blackish ooze leaking out, and insects clustered around the wounds.  Flux is also called “wet wood” or “slime flux”, and is caused by bacteria that gets into the tree. It gets in through breaks in the bark or bore-holes from beetles, and kills the cambium near the openings. The ooze it produces turns black when it hits the oxygen in the air, and the whole thing takes on an “alcohol” smell as it ferments.

Evidence of Alcoholic Flux bacteria, Foamy Canker, Slime Flux, Phytophthora sp., with a Western Yellowjacket, Vespula pensylvanica

According to The Plant Doctor: “…Sap may continue to ooze for several weeks or months, but usually it eventually stops with no treatment and no apparent damage to the tree. This slime flux may be triggered by heat, drought, and other stress…”

I was hoping to see lots of spiders’ webs in the growth along the trail, but beyond sheet-webs, I didn’t see much of anything… except for a beautiful Labyrinth Orb-Weaver spider.  These spiders make webs that are a combination of an incomplete orb web and other irregular strands. The spider makes a “tent” for itself somewhere along the web out of leaves and debris to hide itself from its prey. The one I saw was wrapped inside a leaf that was hung suspended between several very strong vertical web-strands. The spider was hunched inside the leaf with its legs pulled up around its face.  I was able to coax it out so I could get some photos of it.

“…The labyrinth spider is active, with its webs visible, from March through October. During the rainy season, the female mates and lays eggs. The female usually produces 5 or 6 egg sacs with an average of 55 eggs each. She puts her eggs into several silken discs strung together in a bead-like row, and then builds an egg case around the eggs and hangs it in the web near her retreat, where it is camouflaged by other debris in her web. Once the young emerge they are self-sufficient; they leave the mother’s nest by ballooning…”

CLICK HERE for the full album of photos.

I also found an interesting-looking burl on the branch of a cottonwood tree and wondered what caused it.

“…A burl is a tree growth in which the grain has grown in a deformed manner.. It is caused by some kind of stress, such as injury, virus, fungus, insect infestation or mold growth…  The inside of a burl is unique, not like the straight grained wood in the rest of the tree. Cutting open a burl reveals a wood grain that is twisted, contorted and deformed… Burls begin life as a gall…”

I thought the one I saw might have been a large gall caused by a now vacant outcropping of mistletoe, but I’m not sure.

Even though I felt like I wasn’t seeing a lot, I was surprised when I got back to the car that I had been walking for about 4 hours(!).

Species List:

  1. Alcoholic Flux bacteria, Foamy Canker, Slime Flux, Phytophthora sp.
  2. Armenian Blackberry, Rubus armeniacus [pink flowers]
  3. Ash Flower Gall Mite, Eriophyes fraxinivorus
  4. Azolla, Water Fern, Azolla filiculoides
  5. Black Phoebe, Sayornis nigricans
  6. Brazilian Vervain, Verbena brasiliensis
  7. Brewer’s Blackbird, Euphagus cyanocephalus
  8. Brown-Headed Cowbird, Molothrus ater
  9. Buttonbush, Cephalanthus occidentalis
  10. California Wild Grape, Vitis californica
  11. California Wild Rose, Rosa californica
  12. Canada Goose, Branta canadensis
  13. Charolais Cattle, Bos Taurus var. Charolais
  14. Chinese Praying Mantis, Tenodera sinensis [ootheca]
  15. Convoluted Gall Wasp, Andricus confertus
  16. Crampball Fungus, Daldinia concentrica
  17. Denseflower Willowherb, Epilobium densiflorum
  18. Desert Cottontail Rabbit, Sylvilagus audubonii
  19. Eastern Fox Squirrel, Sciurus niger
  20. Flat-Topped Honeydew Gall Wasp, Disholcaspis eldoradensis
  21. Floating Water Primrose, Ludwigia peploides ssp. Peploides
  22. Fremont’s Cottonwood, Populus fremontii
  23. Golden Crowned Sparrow, Zonotrichia atricapilla
  24. Goodding’s Black Willow, Salix gooddingii
  25. Grape Erineum Mite, Colomerus vitis
  26. Great Egret, Ardea alba
  27. Green Alga (freshwater), Chlorophyta ssp.
  28. Jumping Oak Gall Wasp, Neuroterus saltatorius
  29. Labyrinth Orb-Weaver Spider, Metepeira labyrinthea
  30. Marsh Wren, Cistothorus palustris
  31. Narrowleaf Cattail, Cattail, Typha angustifolia
  32. Oak Apple Gall Wasp, Andricus quercuscalifornicus
  33. Oregon Ash, Fraxinus latifolia
  34. Panicled Willowherb, Epilobium brachycarpum
  35. Pin-cushion Sunburst Lichen, Polycauliona polycarpa
  36. Poison Oak, Pacific Poison Oak, Western Poison Oak, Toxicodendron diversilobum
  37. Red Cone Gall Wasp, Andricus kingi
  38. Red-Winged Blackbird, Agelaius phoeniceus
  39. Ribbed Cocoon-Maker Moth, Oak Ribbed Skeletonizer,  Bucculatrix albertiella
  40. Sandbar Willow, Salix exigua var. hindsiana
  41. Sandhill Crane, Grus canadensis
  42. Savannah Sparrow, Passerculus sandwichensis
  43. Snowy Egret, Egretta thula
  44. Spiny Turban Gall Wasp, asexual, fall generation, Antron douglasii
  45. Strap Lichen, Western Strap Lichen, Ramalina leptocarpha
  46. Trashline Orb Weaver Spider, Conical Trashline Spider,  Cyclosa conica
  47. Valley Oak, Quercus lobata
  48. Variegated Meadowhawk Dragonfly, Sympetrum corruptum
  49. Water Hyacinth, Eichhornia crassipes
  50. Western Meadowlark, Sturnella neglecta
  51. White Alder, Alnus rhombifolia
  52. White-Crowned Sparrow, Zonotrichia leucophrys
  53. Willow Apple Gall Sawfly, Pontania californica
  54. Willow Bead Gall Mite, Aculus tetanothrix
  55. Willow Stem Sawfly Gall, Euura exiguae
  56. Woollybear Gall Wasp, Atrusca trimaculosa
  57. Yellow Wig Gall Wasp, Andricus fullawayi
  58. Yellowjacket, Western Yellowjacket, Vespula pensylvanica