Archivos de diario de mayo 2020

01 de mayo de 2020

Mosses of Manhattan

We don't think of Manhattan, NYC, NY, USA as being a particularly "mossy" place, not like overgrown shady ravines in the upstate New York wilderness areas, but when you start paying attention, you discover that mosses are all around us almost everywhere here in the heart of the city: sidewalks, planters, waste ground, edges of paths , etc.

I know almost nothing about mosses, but I figure that my part of Manhattan must be home to only a limited number of moss species because of the air pollution and lack of fully wild habitat, despite Central Park's extensive "imitation wilderness". So I am guessing there might perhaps be 60 species in Manhattan. I suppose Inwood Park is the closest thing Manhattan has to real wilderness, as it is huge with varied habitat and there is some original forest there, but I have yet to make my way to Inwood. When things normalize I will head up there.

I am working with my iPhone, and the camera in the phone is not good at macro/micro pics because there is not enough resolution. However, I am certain there are a number of local mosses that I can learn to ID using the features that are visible to my naked eye, a hand lens, and the somewhat inadequate phone camera.

I already think that I know a small handful of my local moss species, some only to genus. But I could be wrong on some of them -- a little knowledge is dangerous in that way!

One local moss that I have been confident about for a couple of years is Silvery Bryum. I believe that anyone can learn to recognize that moss, even with one hand tied behind their backs.


Here are a few of my few mosses so far:

Silvery Bryum – Bryum argenteum

Seductive Entodon Moss – Entodon seductrix – I may have wrongly ID'ed some of these.

Woody Thyme Moss – Plagiomnium cuspidatum

  • – or could this be another species in that genus?

Bristle Mosses, Orthotrichum, I am pretty sure the genus is OK but I am also guessing I may have in particular O. stellatum, the Starry Bristle Moss. That species ID may be incorrect, but whatever it is, I always find it growing in the crevices of the bark of mature Callery Pear street trees.

Wall Screw-Moss – Tortula muralis

Redshank – Ceratodon purpureus


And with some ID help from a professional moss person, I may also have found:

Common Bladder Moss – Physcomitrium pyriforme

Bonfire Moss – Funaria hygrometrica


The AI/Computer vision has recently started offering some guesses on moss IDs. There are many of them, most of which are probably way off, but here is one suggestion:

Bird's Claw Beard Moss – Barbula unguiculata


Publicado el mayo 1, 2020 01:09 TARDE por susanhewitt susanhewitt | 10 observaciones | 6 comentarios | Deja un comentario

23 de mayo de 2020

Viruses in plants, not people!

Humans are not the only ones who are at risk from a virus. Plants can also be under attack from virus species that are plant pathogens.

Of course you can't photograph the virus itself, but when a plant is infected, you can see the ways in which the virus changes the appearance of the leaves, or sometimes all parts of the plant. The symptoms can be quite striking, and can make interesting photographs. Mosaic viruses cause mosaic-like patterns on leaves. And sometimes a virus can affect a plant in other ways: for example, Cucumber Mosaic Virus, when it is on Nandina domestica, can cause extreme stunting, and make the leaves come out really weirdly: dark red, narrow, and curving downwards.

Some viruses only attack one genus of plants, but some others, including the Cucumber Mosaic Virus, attack a very wide range of plants in different families.

Because many of the viruses have long names, they are usually referred to by their acronyms, so Pagoda Yellow Mosaic Associated Virus is known as PYMAV, and Cucumber Mosaic Virus is CMV.

Here are some plant viruses that I have observed. Please note that @jameskdouch, a virologist in Melbourne, Australia, has given me much assistance by commenting on and correcting my putative virus identifications. And @juhatuomola, a plant pathologist in Helsinki, Finland, has been very helpful too.

Hackberry Mosaic Virus -- on Common Hackberry, Celtis occidentalis

Pokeweed Mosaic Virus -- on American Pokeweed, Phytolacca americana

Cucumber Mosaic Virus -- on Heavenly Bamboo, Nandina domestica

Ribgrass Mosaic Virus -- on Carolina Bluebells, Mertensia virginica

Rose Rosette Emaravirus -- on Multiflora rose, Rosa multiflora

Pagoda Yellow Mosaic Associated Virus -- on Japanese Pagoda Tree, Styphnolobium japonicum


Rose mosaic virus -- one or more of a group of four unrelated viruses which attack Rosa chinensis

Virus on Erigeron:

Virus on Common Blue Violet, Viola sororia:

Mosaic virus on Kirengeshoma (a garden plant):

On June 4th I found symptoms of an interesting, new-to-me plant virus or viroid quite near where I live, on a seedling on White Mulberry. It might perhaps be hop stunt virus, HSVd:


Badnavirus on Japanese Aucuba, Aucuba japonica -- the effects of this virus are highly prized by horticulturists. The virus is transmitted in the seeds from one generation to the next. I guess we have to consider it to be a cultivated virus.


Cucumber Mosaic Virus on Beach Naupaka, Scaevola taccada, in Sanibel, Florida

Begmovirus on Merremia in Nevis West Indies


Publicado el mayo 23, 2020 01:55 MAÑANA por susanhewitt susanhewitt | 13 observaciones | 17 comentarios | Deja un comentario