Black dots on petiole Washingtonia robusta

[MarcusH]

Hi everyone, 

Our first cold front moved in bringing temperatures of mid 30s at night for a couple of days.  This is my palm's first winter being outside in the ground. Since it's raining this morning I thought I would take a look at my washy.  Black dots all over the petioles. What exactly am I dealing with? A disease,  cold temps ? I don't have much experience with palms . 

[Las Palmas Norte]

 Mold? Does it rub off or is it embedded into the plant tissue?

[MarcusH]

Comes off when I rub on it with my nails but I don't feel like rubbing on the petiole since I stabbed myself lol. 

[NBTX11]

It didn’t get cold enough to damage Washingtonia so I doubt it’s that. Big Robusta can take down to 20 or low 20s. With no damage. Small ones probably mid 20s. 

[MarcusH]

4 hours ago, NBTX11 said:

It didn’t get cold enough to damage Washingtonia so I doubt it’s that. Big Robusta can take down to 20 or low 20s. With no damage. Small ones probably mid 20s. 

I guess it was just false alarm . It was the white stuff that was on the petiole before that turned like black spots.  I have a lot to learn.  

[NBTX11]

Yeah I wouldn’t worry about it. Robusta are pretty hardy taking mid 20’s easily. If projected to go below 25 or frozen precipitation forecasted, throw a garbage can over it. Otherwise once it gets established after the first year or two, do nothing. Most winters it will receive little to no damage. It is more tender when young so below 25 could burn fronds. It will grow out of it in the spring. Some winters we do not drop below the upper 20s. Freeze damage will show up in the fronds a couple weeks after a freeze (not immediately). 

Edited November 15, 2022 by NBTX11

[MarcusH]

55 minutes ago, NBTX11 said:

Yeah I wouldn’t worry about it. Robusta are pretty hardy taking mid 20’s easily. If projected to go below 25 or frozen precipitation forecasted, throw a garbage can over it. Otherwise once it gets established after the first year or two, do nothing. Most winters it will receive little to no damage. It is more tender when young so below 25 could burn fronds. It will grow out of it in the spring. Some winters we do not drop below the upper 20s. Freeze damage will show up in the fronds a couple weeks after a freeze (not immediately). 

Thanks for the informing I appreciate it. I've done some research about making palms more cold tolerent . Whenever it gets below freezing ,deepwater the tree and put extra layer of mulch around the base that prevents the roots from freezing and keeps the water supply to the fronds intact.  I assume you already knew about it. 

[ChrisA]

I was thinking it might be the tomentum having gotten wet with that heavy drizzle we have as well. Glad it's doing well! That poke will be one of many with Washingtonia, a rite of passage! 😆

[JohnAndSancho]

1 hour ago, ChrisA said:

I was thinking it might be the tomentum having gotten wet with that heavy drizzle we have as well. Glad it's doing well! That poke will be one of many with Washingtonia, a rite of passage! 😆

I put some lights on my Washy for Xmas in 2020. Maaaaan, that was the day I bought myself gardening gloves. I hamburgered my hands. 

[MarcusH]

21 hours ago, ChrisA said:

I was thinking it might be the tomentum having gotten wet with that heavy drizzle we have as well. Glad it's doing well! That poke will be one of many with Washingtonia, a rite of passage! 😆

I think you're right everything looks back to normal. I wasn't sure what it was since I'm new to palms that's why I asked for advices and this forum is very helpful.  Thank you 

[MarcusH]

19 hours ago, JohnAndSancho said:

I put some lights on my Washy for Xmas in 2020. Maaaaan, that was the day I bought myself gardening gloves. I hamburgered my hands. 

Hahaha I'm sure you did I've pinched myself the first time and I was warned before.  They're razor sharp but us palm enthusiasts can't keep our hands off our beautiful palms

[Foxpalms]

23 hours ago, JohnAndSancho said:

I put some lights on my Washy for Xmas in 2020. Maaaaan, that was the day I bought myself gardening gloves. I hamburgered my hands. 

The teeth on Washingtonia are pretty bad but my daemonorops jenkinsiana is something else.