Japanese Black and Red Pine candle tips browning?

[jd_bonsai]

What is the cause of this browning of 30% of terminal shoots turning brown? Once I pinch these weakened tips off, the plant tissue is mushy.
Too much water? Probably.
Imperfect (not proper bonsai substrate)? Probably.
These are 2 year old pines.
Happening on both JBP and JRP.


(JBP-1 gallon container. I would prefer to put these in colanders . maybe this fall?)

 

[Wires_Guy_wires]

Have you checked for larvae?
I have 2-5 larvae digging away in the buds of my 25 pines every year. I think in my case they're sawfly larvae.

Watering and substrate issues would show through the entire plant in most cases.

 

[markyscott]

What is the cause of this browning of 30% of terminal shoots turning brown? Once I pinch these weakened tips off, the plant tissue is mushy.
Too much water? Probably.
Imperfect (not proper bonsai substrate)? Probably.
These are 2 year old pines.
Happening on both JBP and JRP.


(JBP-1 gallon container. I would prefer to put these in colanders . maybe this fall?)

Possibilities i can think of are pine tip moth, adelgid, or tip blight. Tip moth seems most likely- look for larvae as suggested.

S

 

[Dav4]

Google ‘pine tip moth’

 

[bwaynef]

After you're thoroughly depressed from your research you were pointed to above, check out systemic insecticides, and imidacloprid if you can find it ...and avoid any harm to bees by applying it. (I only use it on conifers, but I've learned to apply early or late.)

 

[Brian Van Fleet]

Google ‘pine tip moth’

Yep.
https://nebaribonsai.wordpress.com/2013/08/31/pine-tip-moth/