Walnut and Pine Tree Problems

Taun Beddes 0:01

Hello and welcome back to the homegrown horticulture podcast on today's episode pine needle scale and the walnut apocalypse. The homegrown horticulture podcast is specifically for the Intermountain West, an area often forgotten about by national gardening companies and even national gardening magazines. We cover anything from home gardening to insect pests and diseases to what might be best to grow in your yard. We really appreciate you listening. And now on with the program. On today's episode, we have Savannah Peterson who is a Utah State University Extension Horticulturist, she works part time in the Utah County Office. We've been experiencing a very high volume of calls about walnut trees with branches dying and just trees looking really unhealthy. Savannah has been looking into this. So Savannah, how are you doing?

Savannah 0:54

I'm doing great.

Taun Beddes 0:55

Appreciate you being here. So what have you been finding out about the walnut trees?

Savannah 1:00

y culprit is something called: 1000

Taun Beddes 1:10

Why do you suspect: 1000

Savannah 1:15

One problem is when trees get stressed like with, for example, drought stress, like we've been having over the past few years, they're much more susceptible to diseases this could have been popping around. But it might be that there's a higher volume because there are more trees that are stressed.

Taun Beddes 1:31

So how is the: 1000

Savannah 1:35

So: 1000

Taun Beddes 2:27

So: 1000

Savannah 2:37

Unfortunately, a lot of diseases have similar symptoms. But some things to look for early on are foliage, yellowing and wilting some thinning of leaves, limb die back can show up later on, and then some more canopy die back.

Taun Beddes 2:54

So how long does it actually once the disease is contracted for a tree to show symptoms,

Savannah 2:59

it can take up to two years, the disease is kind of sneaky and gets a foothold so the beetles are doing their damage and then the fungus is spreading. And then about two years later, you'll start to see yellowing. And by that time, it's way too late. And then it can kill the tree after about another two to three years.

Taun Beddes 3:16

So once the disease has shown up, there's nothing that can really be done.

Savannah 3:21

No, which is a bummer. I think people's gut reaction when you hear about beetles or other insects causing damages to reach for a pesticide. But that's not an effective option here and a waste of money because even if you do kill the beetles, the disease's, still rampant and has already done enough damage that it's not going to recover.

Taun Beddes 3:42

So there is not a treatment that you can actually get the funding goes out of the tree with

Savannah 3:47

No, I haven't seen any fungicides that are very effective or that have been heavily tested. So that's not a viable option either. I think the best bet is to just cut it down and start over,

Taun Beddes 4:01

if you want to try to prevent: 1000

Savannah 4:09

there's two really simple ways to do this. The first one is to actually just not move firewood from place to place, which doesn't seem like it would affect your landscape plants too much. But bark beetles of all kinds have a reputation of just getting into bark, obviously. And then people will cut firewood and move it to take it camping or something and then that'll transmit the Beatles to a new location. So if you are just very careful and don't do that you won't introduce this kind of bark beetle to your home and landscape.

Taun Beddes 4:40

So if you have walnuts at your home, what would be good to do to make sure those walnuts are as healthy as possible.

Savannah 4:47

To big things. Make sure that your tree has adequate irrigation and also fertilize it when it needs to be. Those are just the two basics that'll keep it happy and healthy enough. It's kind of like humans in their immune cell. The healthier you are, the better your chances are of fighting off an infection.

Taun Beddes 5:05

's actually being impacted by: 1000

Savannah 5:09

I believe black walnut,

Taun Beddes 5:11

so black walnut, and then what's the susceptibility of English walnut.

Savannah 5:15

They are also known to be able to contract the disease, but it's much less likely. So if you're going to plant a walnut, that might be a safer bet.

Taun Beddes 5:24

So anything else on: 1000

Savannah 5:27

Man, I hope your trees don't get it.

Taun Beddes 5:29

There's really not much you can do. And so I'd like to transition over to the pine tree problems we've been seeing where there's a lot of Austrian scotch and muco Pines that have been turning yellow and dying. There's, I suppose a few different reasons. So Savanna, which you suspect is causing these pine trees to turn yellow.

Savannah 5:47

drought, stress is always a possibility. But another problem that we've been seeing is scale insect called pine needles skill,

Taun Beddes 5:55

describe pine needles scale, what it does, maybe the life cycle,

Savannah 5:59

I always thought it was a fungus. It's not, it's just a weird like an insect. When it's younger, it's pretty mobile. And we'll just scoot around and chew on and suck out the sap of pine needles. And then when it gets older, it's almost completely stationary. And it looks like a half of a muscle or a clamshell, just glued on to whatever surface it's on.

Taun Beddes 6:23

So you'd have to use a magnifying glass to really see that

Savannah 6:25

Yeah, you would if you get a severe infestation of the white pine needles scale, there's white and black pine needles. But of the white ones that almost looks like your tree is covered in frost because they can get really dense, but it's hard to see the individual insects with the naked eye.

Taun Beddes 6:41

So if people want to try to control pine needle scale, when's the best time to get the pineal skill? I guess the new babies for lack of a better term or mobile

Savannah 6:52

perinatal skill has life cycle that has two generations per year. So the first one usually shows up in early spring and the second one in mid to late summer. It's important that you try to treat pine needles scalp before they turn into adults, because that shell is hard to penetrate with chemicals. So it's easier to do when they're soft bodied juveniles.

Taun Beddes 7:18

So what are those mobile juveniles called? Besides maybe teenagers?

Savannah 7:22

Yeah, nice. They're the crawler stage, which is pretty easy to remember.

Taun Beddes 7:27

The crawler stage I made a dad joke. So how would you monitor for the crawler stage?

Savannah 7:32

One pretty effective and inexpensive way to do it is just using double sided sticky tape on branches, you want to try to stick it pretty close to green foliage so that they'll be by a food source. And then they'll crawl over get stuck. You can go out about twice a week to see what kind of population you have. You have to use a magnifying glass to see if they're there. But you'll at least have a better idea of if they are there and what kind of a problem there'll be later.

Taun Beddes 7:59

So after you've monitored for the crawlers, what would be the options for trying to control these and before we get into chemicals, what would you recommend, as far as non chemical methods,

Savannah 8:10

try to keep your trees as healthy as possible. And then another kind of interesting thing is to try to promote natural predator populations. One thing that I'll eat them is ladybugs and so if you can see Ladybug larva around, I don't know try not to spray pesticide on.

Taun Beddes 8:27

So once you found those crawlers, though, you know you have the scale in the tree and because the scale can be so problematic, what are some reduced risk options that you might suggest to help control the crawlers?

Savannah 8:39

Those would be things like insecticidal soaps or horticultural oils, something like neem oil, those aren't as harsh as other pesticides.

Taun Beddes 8:48

And when would you spray these,

Savannah 8:50

you want to try your best to make sure that you get them in the color stage because once they formed that hard shell, it's a lot harder for chemicals to penetrate in and do their job.

Taun Beddes 9:00

So do you have a preference given that both soaps and oils are fairly available of which one to use?

Savannah 9:05

Yeah, I think your best bet there would be insecticidal soaps. horticultural oils are an option and they're pretty effective, but they can run the risk of discoloring your trees, which is usually cosmetic, but it could do a little bit more damage to So next,

Taun Beddes 9:21

let's say we missed the color stage. What are some options,

Savannah 9:25

some things that will pack a little bit more of a punch to be able to get the adults that insecticidal soaps might not be able to are seven and permethrin. They're registered for trading scale, but they might not catch quite all of the population, they can definitely slow it down. If you need something even stronger than that. There's a systemic called Dinah tough urine. One brand of it is Safari. Another one that's a little easier to get ahold of for homeowners is the ortho tree and shrub insect control. It's found a lot of places you can even get it on Amazon and it's available as a link At granular so there's whichever one you prefer.

Taun Beddes: 10:03

And when is the best time of year to use that systemic. You

Savannah: 10:07

want to do it in early spring. I mean it's especially effective if you can still get it in the color stage but you want to do it before the population gets out of control.

Taun Beddes: 10:16

So we're getting toward the end of the podcast I want to end it on a happier note than what we've been talking about. And so Savannah, you've been out taking pictures of flowers and landscapes for social media for extension, you ran into a flower you especially light

Savannah: 10:31

I did I love it. It's called see thrift, or sleeping says the other name. It's adorable. It looks like a little clump of grass. The technical term is a basil roset and then these long flower stocks up to a teeny tiny head looks like a pompom almost of usually pink flowers. There are some cultivars that are white too, but they're great. They grow really well in Utah, partly because of their name, see thrift. They are native to coastal regions, which means they are extremely salt tolerant. They also have a deep taproot, which means they're drought tolerant, which both of those are great for our area. Deer hate them. So if that's a problem in your yard, this is a plant that can handle all three of those.

Taun Beddes: 11:19

So we'll post on the homegrown horticulture website a picture of the sea beings. And it's I've grown this one in the past, and I really like it. So what's the longevity of it when it's planted in the yard?

Savannah: 11:31

It depends on the conditions four to five years. If you have heavy clay soil or your soil is a little over fertilized or too wet too often, they will last much less time, but the average is about four to five years.

Taun Beddes: 11:49

Well, excellent. Thank you. Thank you for being on the podcast. The homegrown horticulture Podcast is a production of Utah State University Extension. We really appreciate you listening show music is composed by Savannah Peterson, the one and only guest today. We really appreciate her for doing that. We'll talk to you

Transcribed by https://otter.ai