Citrus Scales

[OaklandCityFarmer]

Hey folks- It's been a while since I've been on here! So nice to see so many new faces and some of the old ones too

The issue I'm having is that with the unusually warm and early "Spring" weather we're having here in California my citrus trees kicked into full gear in January. I typically don't spray them with hort oil but I'm having a large infestation of scales. And I don't think that we'll be having cool enough weather anytime soon to allow for a spraying, and they're already flowering for their next crop so might not be a good idea anyway.

Besides broad spectrum pesticides, removing the creatures by hand/spraying them off- any tips would be appreciated. Do they have any natural predators that I can encourage?

As always, any help would be appreciated.

Thanks
Carlos

 

[Smart Red]

Howdy, and welcome back. Pleased as punch to meet you! Wish I could help, but I've found that only three sprayings will do a pretty good job of keeping insect damage off my fruit trees. First, the dormant oil. You say you are too late for that? Perhaps getting the lower trunk and branches would be possible. Second is an organic spray before leafing out. Third is that same spray after blossom drop.

That is a lot less than the recommended 'every 5-7 weeks', but worked well for us.

 

[OaklandCityFarmer]

Thanks Smart Red for the reply. I may just have to use an oil spray like neem on the heavier infested trees and say good-bye to a crop from them. Any sprays that you have used in the past? The issue with oil is that since we are getting full sun everyday here right now, if I spray it's going to burn my trees.

Also, these are the hard scales not the soft shell ones, which of course, makes it more difficult for some sprays to have an effect, especially the contact sprays.

 

[Smart Red]

I thought the oil spray was to cover and smother the scales rather than kill them with chemical action. If I were afraid of sunburn, I'd think about spraying oil and then blowing Kaolin clay dust over the oil. The dust will also keep some insects from climbing the trunk to get to your fruit.

Another thought: instead of the two insect sprays, try Kaolin (also known as Surround). Insects don't like the clay so they don't eat through it to the blossoms or fruit AND it keeps birds from eating your fruit as well since it never looks ripe. Kaolin is a natural clay and is removed with a light rinsing.

 

[OaklandCityFarmer]

You know what, that's a great idea. I've never thought about using Kaolin dust in conjunction with the neem oil. That just may work. I'm going to try it this weekend on one tree and see how that goes. Most of the trunks are covered with a sticky foot type mixture, so not too much of an issue. The biggest thing with these scales is that their whole life span takes place on my citrus leaves, so they just keep multiplying, especially since they seem to love the warm weather.

Thanks!
Carlos

 

[Smart Red]

If you removed the leaves, wouldn't the trees put out new ones in short order? That way you could still get rid of the scales and keep your trees growing and healthy. I doubt you would find flower buds in the second wave of leaves though.

 

[OaklandCityFarmer]

Yeah, it's true that they could take a decent pruning. But some of these trees are pretty big and the scale infestation is somewhat extensive, so I'd have to take out 2/3's of some of the trees. This got way out of hand way too quickly. We've already pruned many of the 3rd and 4th year trees after the February harvest and they seem to be okay in terms of scales.

This is going to be a multi-tactic approach!