American Caesar’s Mushroom (Amanita jacksonii)

August 25^th. I was driving home when I spotted a cluster of mushrooms at the edge of the woods by the road. I knew immediately that they were Caesar’s Amanita (Amanita jacksonii) mushrooms. What surprised me was the size of the largest one. Its cap was 7 to 8 inches in diameter, the largest I had ever seen.

The cluster, from different angles.

The caps of the buds are oval. As they open, the caps become convex, then flat, and finally depressed as are the larger mushrooms in this cluster.

The caps of these mushrooms are solid red, without any scales. Mature caps on these mushrooms have marked striations from the margin towards the center.

Their gills are yellow and crowded, and free from their stems.

Their stems taper slightly from the base to the top and are yellow (or orange) with orange-red fibers, often in zones. Stems have a yellow-to-orange ‘skirtlike’ ring. In addition, one of the most striking things about this mushroom is that the remains of the volva – the membrane that encases the growing mushroom – are often visible at the base of the stem, even when the mushroom is mature. 

These mushrooms may be found east of the Great Plains in the United States where they have a mycorrhizal relationship with the roots oaks and pines. They fruit in summer and fall.

Identification resources: 

- Michael Kuo, MushroomExpert.com: Amanita jacksonii 

- Roger’s Mushrooms: Amanita jacksonii 

Related posts:  

- American Caesar’s Mushroom (Amanitajacksonii)?

- American Caesar’s Mushroom (Amanita jacksonii) Revsited

- Still More American Caesar’s Mushroom (Amanita jacksonii)

Still More American Caesar’s Mushroom (Amanita jacksonii)

August 18^th, 2012. I mentioned before that I was delighted to see the volvas on the American Caesar’s (Amanita jacksonii) mushrooms this year when I’d never seen them before. We were driving down Oscar Walton Road when I spotted two sentinel…

American Caesar’s mushrooms on an embankment beside the road. They were beautifully colored.

The volva was quite evident on the mushroom on the right. When I photographed them, I noticed two more amanitas on the…

top of the embankment nearby. They weren’t quite as photogenic as the first two but…

The volvas on each was clearly visible and the cap on the mushroom on the left had just ‘cleared’ its volva.

Click on an image to view a larger image

Identification resources:

- Rodham E. Tulloss, Eticomm.net: Amanita jacksonii

- Michael Kuo, MushroomExpert.com: Amanita jacksonii

 

Related post:

- American Caesar’s Mushroom (Amanita jacksonii) Revisited

American Caesar’s Mushroom (Amanita jacksonii)?

I saw a couple as we were driving along Hwy 44 but they were orange rather than red; not good specimens. And then, as we drove along the pinewoods section of Anthony Shoals Road in the Broad River Wildlife Management Area, I spotted a cluster that was a brilliant red color. Too good to pass up. So we backed up and got out.

The light wasn’t good. The skies were dark with an impending thunderstorm and the mushrooms were growing on an embankment under the edge of a thick pine woods. So I used LED lights to take some macro shots.

*****

The closest identification I can arrive at, based on comparing photographs on mushroom web sites, is American Caesar’s Mushroom (Amanita jacksonii). The caps are the right color – a rich red with minute vertical striations that are clearly visible in the lower image. I’m questioning the identification because they don’t appear to have volvas and I would have thought that the volvas should still be quite visible at this stage of development. Unfortunately we weren’t able to follow the development of the cap to see if the mature cap also resembled Amanita jacksonii.

Any thoughts on this identification?
Click on the image to view a larger image

Identification resources:
- Rodham E. Tulloss, Eticomm.net: Amanita jacksonii
- Michael Kuo, MushroomExpert.com: Amanita jacksonii