Knowledgebase

Sick Panchito Manzanita #875389

Asked June 30, 2024, 6:41 PM EDT

Hi again, We have several of these in our landscaping. They all look sick, especially in the middle at the main trunk. I pruned a lot of dead material from the one in IMG-5677. It looked better for a little while, then got worse again. I haven't treated the bushes with anything. The only potential problem I found on a quick google search was potential overwatering. I haven't changed anything with the drip for the last couple of years. (I asked a previous question about an oak tree in our yard. I think we agreed it is suffering from some exposure to 2,4-D we sprayed in our pasture). Any thoughts or suggestions would be appreciated.

Larimer County Colorado

Expert Response

Hi again!

This actually could be overwatering - manzanita is a Colorado native and could easily survive with what natural precipitation it receives. It really doesn't need supplemental irrigation, except in periods of extreme drought. 

I don't know how easy it will be for you to check the drip and determine if it's wet or dry below the shrubs, but that would be a good first step. Also, if you're watering more than once a week with the drip, I would greatly reduce that - perhaps twice a month is all that's needed. 

If there's a way to determine how much water you're applying, that is also a good thing to consider. But just determining if it's wet or dry under the shrub is a good place to start.
Alison O'Connor, PhD Replied July 01, 2024, 2:10 PM EDT
I found one 2-gph emitter on each plant. I run the drip zone for 45 minutes every four days. I think it ran yesterday, but none of the plants seemed overly wet (or dry for that matter).
I decided to plug the emitters and see what happens. I have five plants but only four plugs so I'll run a test and see if the four look better than the one still getting water in a month or so.
The worst looking one had some white mold/mildew on a few branches. The bushes are really dense and we don't clean out the fallen leaves in the fall so there are dead leaves and old cedar mulch around the base/trunk. I removed a few of the branches that looked especially bad. 
One plant had a bunch of earwigs around the base so I threw some Ortho bug control around that one.
I'll let you know what happens!

Different subject: The neonics pesticide ban is going to take away my "go to" solution for pests (imidacloprid in systemic solutions by Bayer or FertiLome). I didn't realize it was so bad for bees. Just last week I was telling my wife that it seems we don't have as many pollinators this year. Maybe I'm the problem :(

On Mon, Jul 1, 2024 at 12:10 PM Ask Extension <<personal data hidden>> wrote:
The Question Asker Replied July 02, 2024, 3:52 PM EDT
Hi again,

Sounds like you made some good adjustments - please keep me posted on how they do.

Earwigs generally don't need control. If you have injury to vegetable or fruit crops, you can do oil traps (just set out a shallow dish of oil overnight) or wet newspaper rolls in the areas where earwigs are located. Rarely do they cause enough issue to warrant insecticides.

As for imidacloprid, if you look at the many factors that can affect pollinators, insecticides are fairly low on the list. While we should all be stewards and use insecticides appropriately, factors like urban development, not having host plants for pollinators, poor pollinator nutrition (i.e. honeybees pollinating only one crop, like almonds) etc. are usually bigger factors. So no, you're not the problem. 

But also having a tolerance for some insect damage is a good practice too - a few aphids don't usually warrant control. So it's a matter of assessing the situation and addressing it appropriately. 
Alison O'Connor, PhD Replied July 02, 2024, 5:24 PM EDT

Loading ...