Needle cast in five needle pines?

[NMbonsai]

Somewhere on one of these threads, someone referenced a study that said that needle cast only affects two and three needle pines. Is this true?

 

[MaciekA]

It's not true. Needle cast is an umbrella term describing a rather huge number / range of species/genera on both the host and pathogen side, so we should be careful in making absolutely final/global statements.

You can read scholarly papers that document needle cast in 5-needle species both in North American and in Asian species, here are some examples:

• Eastern white pine: https://scholars.unh.edu/thesis/1067/
• Eastern white pine: https://www.mdpi.com/1999-4907/6/11/4088
• Korean pine: https://agris.fao.org/search/en/providers/122431/records/64775162f2e6fe92b364a041
• Lophodermella (one of the well-known needle cast genera) on western US 5-needle pines (whitebark, limber, etc) AND ornamental white pines: https://pnwhandbooks.org/plantdisease/host-disease/pine-pinus-spp-lophodermella-needle-cast

A statement like "needle cast only affects two and three needle pines" can't be something that a recent scholarly study said because some of these references go back as far as the 1990s, so it raises the question of what that other cited study was really saying.

FWIW, every time I hear the term "needle cast" I instantly think of bonsainut, because it's the only venue in my life (digital or IRL) that discusses it as much as this. I spend a ton of time with pine growers and in pine bonsai gardens and needle cast is hardly discussed and not really feared at all. On this forum though, it has a fatalistic cancer-like aura. I'm curious what a study of that would reveal, it's hard to tease out any trends except "people on bonsainut sure do talk about needlecast a lot" Perhaps bnut should gather data of its own over time to figure out who gets it, where, why, and when. Some growers I know basically never have to deal with it but it seems that some on this forum are completely beset with it. Would be nice to be a fly on the wall and suss out the truth. At times I've speculated that it's a humid summer climate thing, but it's hard to tell.

 

[NMbonsai]

It's not true. Needle cast is an umbrella term describing a rather huge number / range of species/genera on both the host and pathogen side, so we should be careful in making absolutely final/global statements.

You can read scholarly papers that document needle cast in 5-needle species both in North American and in Asian species, here are some examples:

• Eastern white pine: https://scholars.unh.edu/thesis/1067/
• Eastern white pine: https://www.mdpi.com/1999-4907/6/11/4088
• Korean pine: https://agris.fao.org/search/en/providers/122431/records/64775162f2e6fe92b364a041
• Lophodermella (one of the well-known needle cast genera) on western US 5-needle pines (whitebark, limber, etc) AND ornamental white pines: https://pnwhandbooks.org/plantdisease/host-disease/pine-pinus-spp-lophodermella-needle-cast

A statement like "needle cast only affects two and three needle pines" can't be something that a recent scholarly study said because some of these references go back as far as the 1990s, so it raises the question of what that other cited study was really saying.

FWIW, every time I hear the term "needle cast" I instantly think of bonsainut, because it's the only venue in my life (digital or IRL) that discusses it as much as this. I spend a ton of time with pine growers and in pine bonsai gardens and needle cast is hardly discussed and not really feared at all. On this forum though, it has a fatalistic cancer-like aura. I'm curious what a study of that would reveal, it's hard to tease out any trends except "people on bonsainut sure do talk about needlecast a lot" Perhaps bnut should gather data of its own over time to figure out who gets it, where, why, and when. Some growers I know basically never have to deal with it but it seems that some on this forum are completely beset with it. Would be nice to be a fly on the wall and suss out the truth. At times I've speculated that it's a humid summer climate thing, but it's hard to tell.

Thank you for your explanation. Needle cast and concerns about it do seem to generate a lot of postings on this website. After I posted this, I went back through some of the threads here on Bonsainut but could not find the link to that article i referred to. I did learn while doing my own research that what is called 'needle cast' actually refers to a group of fungi that can display a wide range of symptoms other than the classic yellow banding that is so often referred to and photographed on these threads. Even in these postings, there are many different symptoms attributed to it, including the yellow and brown banding, blackened needle tips, as well as whole needle clusters turning brown. I have been doing bonsai for a number of years but have only recently started working with pines; mostly JBP as well as the Southwestern white pine, P. strobiformus. Being in such a low humidity desert climate, I was surprised to see the yellow and brown banding appearing on a couple of my JBPs. None of the white pines are showing these symptoms. Both of the affected trees were recently purchased from a nursery in the Pacific Northwest, so I assume that they were probably infected before being shipped here. I have never seen needle cast on any of our native pinons or Ponderosas. After reading the treatments recommended on many of the threads here, I have decided to use a granular systemic on all my black pines but wait and see on the white pines. I will also do a spray with Daconil next spring when the new buds start to open.

 

[NMbonsai]

Thank you for your explanation. Needle cast and concerns about it do seem to generate a lot of postings on this website. After I posted this, I went back through some of the threads here on Bonsainut but could not find the link to that article i referred to. I did learn while doing my own research that what is called 'needle cast' actually refers to a group of fungi that can display a wide range of symptoms other than the classic yellow banding that is so often referred to and photographed on these threads. Even in these postings, there are many different symptoms attributed to it, including the yellow and brown banding, blackened needle tips, as well as whole needle clusters turning brown. I have been doing bonsai for a number of years but have only recently started working with pines; mostly JBP as well as the Southwestern white pine, P. strobiformus. Being in such a low humidity desert climate, I was surprised to see the yellow and brown banding appearing on a couple of my JBPs. None of the white pines are showing these symptoms. Both of the affected trees were recently purchased from a nursery in the Pacific Northwest, so I assume that they were probably infected before being shipped here. I have never seen needle cast on any of our native pinons or Ponderosas. After reading the treatments recommended on many of the threads here, I have decided to use a granular systemic on all my black pines but wait and see on the white pines. I will also do a spray with Daconil next spring when the new buds start to open.

Photos of the JBP referred to in the above reply.